Sunday 6 December 2009

Yokes.

The time has come to put two proper slabs of billet in the mill and make the yokes that will replace the iron ones I've been using during the construction process. This will not only lighten the bike by some two metric tonnes, but also address the problem with the lack of ground trail that the friendly MOT-man pointed out last week. By reducing the offset [the distance between the center of the steering stem and the centre of the fork legs] by 20 mm, I will move the front axle 20 mm backwards. This will INCREASE the trail by the same amount, giving me appr 85-90 mm ground trail, and hopefully a stable, yet nimble bike.

I couldn't find a good place to mount the front indicators on the bike, so I thought I'd try to incorporate a mounting point at the back of the top yokes. This way I can route the cables through and under the top yoke and hopefully get an uncluttered look to the front end. The Swedish law states that the indicators must be mounted 240 mm apart, so mounting them onto the headlight is not an option.

The red number 1 points out the mounting holes for the risers, number 2 is where the Trailtech computer will be mounted and number 3 is the mounting point for the Bates headlight.

Monday 30 November 2009

Virtual paintshop.

The time has come to paint my pride & joy and I'll start sending out parts soon. The frame, along with the soon to be new triple trees, will be powder coated matt black. The back wheel gloss black. The thinking behind this is that a subdued colour scheme for the chassis will form a nice backdrop for the tank and seat unit.

I guess I could go for a really edgy paint scheme that will be truly memorable, and set it apart from all other street trackers. Something that would really stand out from the crowd. But that was never the point of this bike. I fell in love with the style of flat track bikes, and I want my bike to be instantly recognizable as a flat/street tracker – even if I've chosen a modern motor and modern brakes and suspension. I also wanted to incorporate something of the Husqvarna heritage from the time when a Husky was THE bike to have if you were a motocrosser or enduro rider. That's where the logo comes from incidentally. It's the same logo that was on Steve McQueen's personal Husqvarna bike (sans the black outline)

So this is where I am at the moment (see image). It may change somewhat, but it will resemble this Photoshop composite with the two-tone red and contrasting white panels. Trust me when I say that I've tried every conceivable combination of Husky/ruby red, black and white:-). The ruby red will get a subtle flake treatment, the whites will be solid.

Tuesday 24 November 2009

It's Beginning to Look a Lot Like Christmas!

Yeah, I know that those red, flake grips are a little bit over the top, but I couldn't resist when I found them on ebay and thought that they would be a nice match for my soon to be red bike. They're proper vintage "balloon" grips, made by an Italian firm called "Granturismo" and according to the fact sheet they are "make [yes: make] to absorb the roughest of vibrations". A good thing, since my Huskvarna engine vibrates like a pneumatic drill on nitro. If they turn out looking too garish on the bike, I'll order these from the Wrench Monkees. Check out the cool little glass vial of rubber cement that has survived perfectly ever since the grips were manufactured, which may have been in the seventies(?). They may also have been made last week in China and are sold as "vintage" to suckers like me...

The lovely little billet tank cap is made by the same guy that made my XR-style tank, many moons ago. As per usual when it comes to people in the flat track business, he was more difficult to locate than Saddam Hussein. Impossible to find on the interweb, and of course: he didn't accept credit cards. Once found (thank you Richard of Mule Motorcycles), he turned out to be a very friendly chap (also typical of the flat track scene) and promptly sent me the tank cap and a few other bits and bobs that I needed. His name is Fred BTW, and his company is called RaceTec and he's the one who actually makes the tanks that are subsequently sold by Storz. I don't know if it shows up on the image, but the quality of the milling of the cap is quite superb.

Sunday 22 November 2009

Motorcycle manufacturer...me?

First of all: forgive me reader, it's been a long time since my last post.

You know how it goes: someone asks you to "assist a little in a project we're doing" and before you know it you are working flat out, day and night for a month and a half. Oh well, at least the pay was good. But if anyone so much as mentions the word "PowerPoint" to me before the new year, I'm going to go ape.

Big things have happened since my last post. I took my bike to the "SFRO"-man yesterday to get a preliminary OK for me to go ahead and finish the build. To make a long story short: in order for me to get my bike approved for the streets here in Sweden, I have to go through a series of steps. The first, and biggest, is the one I completed yesterday. Before I can paint my frame, I have to show my bike in a semi-finished state to a guy who is a certified inspector for "SFRO" – an organisation that performs inspections for the "department of traffic security". The rules governing what you can build and take to the street are actually quite liberal in Sweden, but they [SFRO] nonetheless want to make sure that people don't kill themselves on poorly constructed death traps. Fine with me.

So, I loaded up my bike and drove the 80 clicks to a place called Svedala, just outside of Malmö, where I met with the inspector. I had half expected him to give the bike a cursory glance and then give me the go ahead, but he took to his work with the fervor [and humour] of a preussian customs officer. He crawled around the bike, looking at every weld seam, every bolt and every nut. He even spotted the absence of a "certified for the street" marker on my tires, despite the fact that I had buffed out the "for racing use only" lettering. A process that took me several hours to get right. So now I need to borrow a couple of street legal 19 inchers for the next time I go back. After much sucking of teeth and scribbling on notepads he gave me the verdict: as long as I add another 15 mm to the trail, and get the tires sorted, he would give the bike his blessing. Result!

Adding some more trail is no biggie since the tripple trees are still in prototype form and by reducing the offset a bit on the finished items, I will get more trail. I can also lower the back a little which will give me the same result.

Then came the paperwork. In order to stop people from putting together a host of stolen bits and pieces and then registering their collages as "new bikes" and thereby entering them again into the system, you have to show proof of purchase of the major components and produce the papers that show that you are the rightful owner of the engine etc. Again: cool by me. I also got my new 17 digit frame number and the SFRO-guy, who by now had lightened up a bit, stamped the new number onto the side of the stearing head. He them proceeded to take photographs of the bike and the new ID-number. My bike was now officially a new product with a new identity.

While filling out the remaining paper work he went through the list of questions: "Capacity?". "577 cubic centimeters" I answered. "Tank capacity?". "Oh, about 8 litres". "Make?". "Eh...Husqvarna..." I started, before he interrupted me. "No, no" he said. "That was before you made something totally different of this bike. You can't register it as Husqvarna any longer, you are now the official manufacturer of this bike as far as the authorities goes. So who is the manufacturer of this bike?". "Erm... Krook Street...I guess?" And then it struck me: Krook Street, i.e. me, is now an official motorcycle manufacturer. Who would have thunk it!?

Monday 26 October 2009

Wavy discs. No longer only for poseurs.

I have to admit that I chose my Braking wave rotors solely for their, erm... aesthetic value (i.e. I thought they looked cool). Imagine my surprise when I flipped through the pages of the latest issue of Performance Bikes, and found their test, aptly named, "Do wavy discs work?". It turns out they do. They (PB) swapped the standard discs on an R1 for the exact same disc type that I'm using, and the wavy beauts actually made the big Yamaha stop quicker. Significantly quicker in fact. They suffered less fade too. What was it they used to say at the Bauhaus school? Function follows form? or was it the other way around?

Friday 16 October 2009

Fruit of the loom.

Does anyone know where all this crap goes? Jokes aside, I actually took the precaution of labeling most of the connectors, before I tore the bike down. Thankfully, the wiring loom is quite straightforward. It's no Gold Wing after all. No hand warmers, no GPS, no radio, not even a battery. My only concern right now is how to feed the Vapor computer with power, without running the risk of frying its little electronic brain... If it comes to that, I might have to read the instructions. Even if I consider that cheating.

Wednesday 14 October 2009

Exhaust hanger.

I mentioned that I didn't like the look of the standard exhaust hanger clamp/band that was supplied with my Supertrapp exhaust. And that I wanted a somewhat tidier looking solution. This is how it turned out.

We welded a little stainless "stud" (is that the word?) with some M8-treads in it onto the back of the exhaust, bolted a new hanger to the stud and then welded a mount for the hanger on the underside of the tube supporting the seat unit. The hanger was laser cut out of 3 mm stainless, which is a little bit too Krauss-Maffei, but there was a little bit of a miscommunication over the material choice between me and the supplier... Since I had planned to powder coat it black anyway, and the hanger isn't very heavy, I chose to keep it. It's too bad you can't make a whole frame out of stainless (It's too brittle) – I just love the feeling of longevity you get with properly manufactured stainless pieces. Pardon the crap mobile phone-image.

Wednesday 30 September 2009

Rear brake master cylinder.

My idea of keeping the bottom part of the original Husky frame, rather than fabricating that too, has so far proved to be a good one. Most of the fittings can be used "as is", and the engine mounts are already there, which of course saves time. However, since my new swingarm has a kink just after the bearings (number 1) it is now impossible to mount the rear brake master cylinder in its original place - since that space is now taken up by the new, wider swingarm. Instead, I have mounted it on the outside of the original bracket with the help of a couple of small spacers (number 2) that will be welded to the frame before I send it off to paint.

Despite the fact that is now sits a little bit further out, It's actually not in the way of my foot, but the relocated master cylinder necessitated a slight mod to the brake pedal in the form of a new, straight, tab at the back (number 3). The original was bent inwards. BTW: don't you just wish you could weld alu like that? Thanks Kent. The original brake line was waaay to long for the now much shorter swingarm and has been replaced by a new steel spun one. If I can muster the energy, I will try to replace some of the ugly hardware on the brake cylinder with some stainless pieces. Damn, there is not too many things left to do now. Next up: getting the chain line perfect.

Thursday 24 September 2009

Brake hanger, part 3.

I got my brake hanger back today after my friendly fabricator Indiana had shaved off some 6 mm, leaving the full 15 mm only where the brake caliper bolts to the hanger. These are my findings on the subject of laser/abrasive water jet-cutting of thicker alu pieces:

"Daws" mentioned that the program I'm using – Adobe Illustrator – is not very good at generating AutoCAD-files and that the resulting curves are not as easy for the cutter head to follow as curves resulting from a proper CAD-application. And he does have a point. Looking at the cut surface (see image 1) it's obvious that the cutting head/water jet hasn't described perfectly smooth radiuses (radii?). It looks a littble bit as if the cutter head has paused/started/wobbled around a bit. This may of course be a characteristic of the water cutting method, but I suspect that it has something to do with the file as well. He also cautioned me that the cut surfaces won't be 100 "parallel" but rather have bit of taper - also a characteristic of the cutting method. Again, he was correct. It wasn't super obvious though and I'm not sure I would have noticed if I wasn't looking for it.

So, is it a worthwhile method? Yes and no. It's a quick and relatively cheap way of turning out pretty complex shapes without having to resort to more complex CAD/numerically controlled milling. On the other hand, the resulting pieces are nowhere near as perfect as pieces done using a mill. I spent three hours cleaning up and smoothing/straightening the edges in order to make it look like I wanted (see image 2). The surface isn't perfect yet – I'll leave the final polishing to the anodizers.

Conclusion: I think I'll save this method for thinner pieces in the future. And I'll use the freeware application "Solid Edge 2D Drafting" that Daws recommended.

Tuesday 22 September 2009

I give up.

Damn that Pareto guy and his damned 80-20 rule. You know the one that states that "80 percent of a company's revenue comes from 20 percent of its products" or "80 percent of all speeding violations are committed by 20 percent of the drivers" etc, etc. In my case it's: "80 percent of the build time is taken up by 20 percent of the components". Make that "stupid small stuff that I hadn't expected to be such a hassle".

At the moment it's the speedo issue that's driving me crazy. The speedo drive turns the cable 2,8 revolutions for every revolution of the wheel (I've measured it). When I mention this fact to people who sell speedos, the line goes quiet. Then they start babbling that "Most Harley Davidsons..." or "I know that old Shovels use a 1:1 ratio..." or something else irrelevant (99,999 % of all aftermarket speedos are for Harleys, it appears). And when I add that I now have a 19 inch wheel (rather than the 17 inch wheel of the Ducati 996 that the speedo drive comes from) they tell me – in order to make me go away – that I will never be able to get the correct gearing ratio. And without the correct ratio the speedo won't show the correct speed. And that means I won't be able to get my M.O.T.

"Well, change the speedo drive then", I hear you say. But, alas, I can't. The front spindle is 25 mm and the only speedo drive large enough is the Ducati one I already have. I've thought about some sort of solution where I could machine the spindle down to something like 20 mm (so that I can use some kind of jap speedo drive), but then I need some sort of sleeve to thread over the the end of the spindle, in order for it to fit the forks, and I don't like that thought at all. And besides, I don't want to throw away my exquisitely machined, hollow, stainless spindle.


So. Enough is enough. I've decided to eat my words, and go with an electronic speedo. I've found one from trailtech. It's called Vapor Stealth, it's black and it's OK looking. The superbly helpful technician I spoke with (why are all US help line operators so genuinely helpful and friendly BTW?) informed me that the installation is quite easy and even the RPM tachometer graph works on my Husky (despite the fact that it didn't come with a tach to start with), using a simple lead that wraps around the spark plug lead.
Looking at my front disc I now realise that the good people at Braking had foreseen my failure to sort the mechanical speedo and have machined a little eyelet for the sensor magnet into the disc carrier. Hm...

Friday 18 September 2009

Brake hanger, part 2.

Do you remember the abomination of a brake hanger that I showed you a while ago? Well, the time has come to make a proper one. This is how I go about it. There are of course a lot of ways that you could do it, but this is an easy one, especially if you are familiar with Adobe's wonderful vector-drawing application "Illustrator".

The prototype made from scrap pieces of steel (top part of image) is fundamentally correct, but has an awkward shape that I want to improve on. I also want to add some "meat" to certain parts of the hanger now that we're switching from steel to aluminium. So I put the prototype on a flat-bed scanner and place the resulting JPEG-file as a background image in a new Illustrator drawing.

Using vernier calipers, I take some really exact measurements of the real thing (length, width, size of the hole for the steel spacer) and make sure that the scanned image of the hanger gets the exact right size in Illustrator. Now that I have the scanned image as a background/template in the right size, I can draw a nicer looking hanger "on top of it" and still get the measurements correct and the needed holes in the right place (lower part of image). Once satisfied, I do a printout of my new hanger in 100% and check against my prototype.

Finally, I export the Illustrator file as an "AutoCAD Drawing"/dwg file and send it off to the laser/water cutters. If all goes according to plan I will receive a 15 mm thick alu part cut to my specification next week. This part will need a little bit of milling to get the right thicknesses (its thicker at the back) but it's still easier than doing the whole thing in the mill.

BTW:
The reason why the hanger is a little bit longer than normal is that I want to be able to secure the "tuning fork" part of the hanger to the little stud inside the swingarm that keeps the hanger from rotating, using a screw. And in order for me to get to that stud it needs to be welded a little further forward on the swingarm – to clear the brake disc. The hanger will be black and most of it will be hidden by the black swingarm anyway so that's no problem.

Wednesday 16 September 2009

Help!

Can anyone point me in the direction of a mechanically driven speedo that would work together with my Ducati speedo drive? I can't find one I like. This one from Deus is passable, but surely there must be a firm somewhere that specialises in old school mechanically driven speedos?

Tuesday 15 September 2009

Star Bars.

Well, that's the name: Star Bars. Supplied by Outtacontrolla from his "Red Max Speedshop" at a very reasonable 80 quid including postage and packaging.

When I unpacked them my first thought was: damn they are REALLY wide. But once on the bike they give that flat special flat track look that is so hard to describe to people who never heard of the sport. And they look quite well made too. Glossy black [of course] anodising, matching the forks perfectly and with a really nice matte, almost crackelated finish on the "bird pearch" as we call it i here in Sweden. And what's even better: they don't have any ugly painted logos or anything like that. Just a small and tasteful "Star Bars" embossing on the central part of the bars. You see, we want the designer stuff – we just don't want it to be too obvious:-)

Sunday 6 September 2009

Picture, thousand words, etc.

Now, if you've been in any way inspired by my little build and is currently sitting in your garage, espresso in your left hand and angle grinder in the other, thinking; hm, that old Gold Wing might look good with a new frame and some 19 inchers, then by all means go for it. But before you tear your bike to pieces, do yourself a favour and take lots of pictures, from all possible angles. Trust me, you will thank me later. I am at the moment trying to modify my wiring loom to fit my now totally modified bike, and the pictures I took before starting the disassembly are really worth their weight in gold (if a digital image actually weighs anything...?).

On a side note: looking at my "before-pictures – what a terribly messy job the Italians did with the wiring on my original Husky! It looked like a Calcutta street corner, loose wires hanging everywhere. I promise to do a much neater job this time around.

Wednesday 2 September 2009

Angle of dangle, part 2.

I've said it before, but it bears saying again: it's a good thing I don't do this for a living. I've been dicking about with the angle of the muffler and the connecting pipe now for days, without finding that elusive, perfect solution.

I tried the shallower, scrambler-looking position (see last post) for the muffler for a couple of days, but I just COULD NOT get the
link pipe between the 2-into-1-pipe and the muffler to look good. The angle and curvature of the link pipe clashed terribly with the angles of the frame. It looked like an afterthought (which in essence it was - but don't tell anyone...). I now have a whole heap of discarded pipes on my work shop floor, and a new-found respect for people who make exhausts as a regular job.

As you can see, I have now gone with a much steeper angle for the muffler, which makes the link pipe much easier to get right. It's now parallel with the support strut for the seat and doesn't break with the overall lines of the bike. The increased angle (which was suggested by "Outacontrolla" BTW) actually looks more flat track than Scrambler as well. Or is this just my brain trying to justify my decision to give up on the other position? Hm. Next up: moving the mounting point for the muffler a little bit backwards and fabricating a little hanger to replace the strip of duct tape. I don't fancy the "clamp hanger" that came with the muffler.

Thursday 27 August 2009

Angle of dangle.

My Supertrapp exhaust arrived yesterday and I'm now trying to decide on the optimum position for it. I've tried quite a few different angles and found that a slightly forward sloping angle works best (see image).

Marcus of Marcus Moto Design, gave me some feedback on my first attempt and suggested that I put the exhaust as high as possible in order to show off as much as possible of the wheel. A valid point and I have now moved it up as close to the seat unit as I dare
(I don't want the heat to spoil the paint). Looking at the image now, I think I'll try to lessen the angle a little bit further to make it a little bit more parallel with the seat unit (also one of Marcus' suggestions). But I still want to keep a little bit of forward lean. I tried the fully parallel route but it looks to static and "slow". What do you think?

I may add a laser cut polished stainless heat shield with the same style holes as in my radiator guards, for that old school scrambler look. More on that later.

Tuesday 25 August 2009

Spot the difference?


Have you ever noticed that 99% of all bikes have the speedo drive on the left side of the front wheel? Neither had I. Well, at least not until I started to look for a new speedo drive to replace the original one on my Husqvarna, which for some unknown reason was mounted on the right side.

Since my new front wheel spindle has a diameter of 25 mm – in order to fit my Gixxer forks – the old 20 mm speedo drive wouldn't fit, and couldn't be modified (like enlarged/drilled or something like that). After a lot of digging in the intertubes, I found that some Ducatis use a 25 mm front spindle and I finally found a drive from a 996 at my local breakers in Fleninge outside of Helsingborg, who incidentally is THE least service minded and friendly establishment I've ever had the displeasure to visit. Anyhoo, the problem is, as you can see in the image, that the Ducati drive is meant to be mounted on the left side and can't be flipped over and mounted on the right side, since it then spins the speedo wire backwards. And there is simply not enough room on the left side where the disc carrier gets in the way of the speedo cable...


At this point you are probably asking yourself; why the hell doesn't he stop this nonsense and mount a modern little magneto driven speedo instead? Well, first of all: I like a challenge, and secondly: I really want a nice looking proper mechanical speedo, and not some poncy liquid crystal, glorified pedal bike computer. I know that the 996 drive won't be very exact since it's calibrated for a 17 inch wheel, but that a compromise I can live with.

I sat wracking my brains for hours on how to modify the drive gear or the spindle in order to make it all fit. Then it suddenly struck me. What if I simply flip the wheel over? After all, I can just as well run the brake disc on the right side... I'm not entirely sure if this means that I have to exchange my Tochico brake caliper for a right side one, or if mine can be used, but that's a small issue. Time to start looking for a nice looking speedo. Any suggestions?

Saturday 22 August 2009

Let there be light.


After yesterday's realization that I had made a mess of my gearing calculations, it feels good to be able to report that the Bates 5 3/4'' old school headlight I bought from a German web shop, looks perfect in its new home between the [still prototype] fork legs of my tracker. Next week it will be adorned by a mesh grille taken from Triumph's accessory program.

And if you think you've already seen that particular combo (black Bates light /Triumph Scrambler mesh) on a street tracker somewhere, you've probably visited the fabulous website of the bike brand with the most pretentious name in biking history: Deux Ex Machina. Their super cool "Mono" has exactly the same combo. In fact, I sent them an email about where that cool mesh came from, and they were kind enough to send me in the right direction.


Originally, I had planned on using a front number plate with a small projector light poking through one of the digits, but since Richard Pollock of Mule Motorcycles thinks number plates on street trackers look "goofy" [see sideburn #3], I went with this setup instead:o)

Friday 21 August 2009

Bollocks!

Me and my big mouth. I should have used one of those gearing calculators after all (see last post). Instead of lowering the sprocket ratio by 15% I should have increased it by 15%. In other words: I need a larger rear sprocket than standard for my now larger wheel (too make it spin slower). Not a smaller one (which makes it spin faster). In fact, I need a 52 tooth rear sprocket (if I use my 16 tooth front). Learning by screwing up. Now, where did I put that phone number to Talon again?

BTW: does anyone need a 42 tooth rear sprocket for a PM-wheel. Never used...


Tuesday 18 August 2009

Gearing.


In its original state, my Husqvarna SMR ran a 48/17 sprocket combo. But that was with the dinky little 17 inchers. Now, with the huge 19-inchers, and the swollen Maxxis flat track tires, we need a different gearing altogether. There is no shortage of "gear calculators" to be found on the web and some are really OTT (here's one), but some simple maths is actually enough.

Here goes: The stock sprocket ratio is
48/17=2,83. The standard tire (150/60-17) had a circumference of about 1,92 meters.The new tire has a circumference of about 2,20 meters, i e about 15% bigger. That means we need to lower the sprocket ratio by the same amount (15%) to get the same "total gearing". 2,83/1,15 comes out to about: 2,46, which is our target ratio. I wanted to keep the front sprocket with 17 teeth and only change the rear sprocket. So I chose a 42 tooth rear sprocket, giving a sprocket ratio of 2,47 which is pretty close to what I need. I've always thought that the original gearing was a little long and I have a 16 tooth front sprocket in reserve should the gearing turn out to be on the long side.

BTW: does anyone know of a company that sells stainless Allen bolts with "countersunk" heads in 7/16''? The ugly hex bolts I'm using now have to go. I've been googling furiously, but to no avail.

Thursday 13 August 2009

The missing link.


My 570 Husqvarna engine has two exhaust ports and two 32 mm stainless exhaust headers. These two headers continue separately all the way back to the muffler (image here), which limits the choice of aftermarket mufflers to a a few specially made for the SMR/TE570. All of these have the same problem as the standard muffler: they are very long and looks terrible on a flat tracker. So, in order to run a smaller and better looking muffler I needed to somehow link the two header pipes into one larger pipe. And as it happens, the more recent Husqvarnas share the 32 mm headers, but use a 2-into-1, Y-shaped connector pipe followed by a larger diameter link pipe back to the muffler. For some reason, this 2-into-1 pipe is not availble as a spare part from the dealers – You have to buy the whole system... But as usual, Ebay came to the rescue, and I was able to find this stainless little time saver (It saved me the work of trying to find suitable stainless tubes, bending and welding them). The part number is A0868. Next up: trying to decide what type of Super Trapp muffler to order...

Monday 10 August 2009

Rear light.


Another piece of the puzzle falls into place. I've been looking for a rear light on ebay for for some time, but not been able to find a suitable one. They were either too large – most jap/standard bikes use huge rear lights – or just too flimsy/ugly. I've also visited my local breakers yard looking for something that might fit, but to no avail. However, a trip to a nearby place catering to cruiser/chopper types (let's keep that one under wraps shall we), solved my problem. I would have prefered a red lens since I think clear lenses are bit chav, but none was available. So this one had to do. At least it looks well made, and I think the rounded shape snuggles up quite well under the seat unit. I know from experience that the vibey Husky engine kills off lightbulbs at a frightful rate, so I've put some extra rubber bushings between the lamp housing and the "carrier" to protect the diods. The "carrier" (professional builders look away now) started life as a bracket inside a PC, but an hour or so of cutting and drilling later, it now serves a bigger purpose in life. Isn't recycling great?:-)

Saturday 25 July 2009

Heads up.


Now, this may be totally obvious for those of you who've already built a couple of street trackers, but I must admit to have been a little dumbfounded about how to best attach the seat unit and seat pad.

My seat pad from "First Class Glass" came with a set of rubber mounts and screws. You're supposed to push the rubber mounts into the seat base from underneath, make corresponding holes for the screws in the carbon fibre seat unit (the central of the three holes in the picture), thread the screws through the holes and into the rubber mounts. As you tighten the screws, the rubber mounts inside the seat padding expand and lock everything in place. So far so good. But how do you fix the seat unit in place on the frame, without bulky screws and washers between the seat pad and the carbon fibre? An email to the ever helpful J-W of Dutch Brothers gave me the answer: BigHeads. Mine are – as you can see – home made (from stainless), but they do the job perfectly.


Wednesday 22 July 2009

Radiator protectors, part 3.


The radiator protectors are now bent into shape and they actually fit perfectly. When painted/anodized black I think they will look quite good. However, if you are going to do this yourself, don't go for 2,5 mm aluminium sheet like I did – it's too stiff and makes the bending very tricky indeed. 2 mm sheet is quite enough, or even 1,5. It's not meant to be bullet proof after all.

And one more thing: I designed little "notches" into the design (see earlier post), to guide me when bending. In retrospect, that was unnecessary and the notches "flared out" in the corners and looks unsightly after bending (probably because of the thick material). I will ask Kent to fill the notches with some weld and then I'll file and sand them smooth again before I send the pieces off to be anodized.

The protectors will restrict the airflow through the radiators a bit, but since the engine has two quite big coolers I think I will be allright. As long as I don't drive too slow:-)

Tuesday 21 July 2009

The proverbial sieve.


Did I mention that I was a little bit irate after I had had my tank paint stripped? What was to be a simple case of getting the old and [super] ugly paint removed and then sending it off for a respray, turned into a real hassle. Not only were there huge bondo-filled dents in the tank, when pressurized and submerged in water, we counted 20 (yes, twenty) little holes in the weld seams underneath! It leaked like a sieve that someone had shot up with buck shot for good measure. Thankfully, Kent "the aluminium wizard" managed to not only plug the leaks but also push out the dents from inside, after having cut numerous holes in the bottom of the tank and subsequently welded them shut again. I just wish I had real world skills like that...

What can be learned from this? Well, I for one will never again buy a painted tank from someone I don't know. And I will probably look into having a custom tank made from scratch next time. It's not THAT expensive and will probably save me a lot of aggravation. Kent gave me a quote for a scratch built tank resembling my Storz tank that was well below what it has cost me now. Grrrrrr.

Sunday 12 July 2009

Radiator protectors, part 2.


As you can see, I've been busy over the weekend with my drill and file, creating these radiator protectors. Just kidding – I sent the drawing (see earlier post) of my radiator protectors to a company who specializes in laser cutting and two days later I found these in my letter box. It's amazing what you can achieve with some basic Illustrator skills and the equivalent of about 80 Euros. The laser cutting process is so precise that the plates only needed a very light clean up with some emery paper, where the aluminium had melted and formed little "blobs". And a little softening of the edges.

Next thing to do is to bend the the side plates (look closely and you'll see that that there are little knotches cut into the plates, to guide me when bending) and drill the bolt holes where the retaining bolts go. Then they are off to be polished and anodized. I decided on anodizing, rather than paint, since they are going to sit very close to the rather hot radiators.

Monday 6 July 2009

False economy.


I'm slowly beginning to understand why no one was very keen on taking on the job of making a custom frame for my Husqvarna motor when I started this project. It's a massive undertaking building something like this from scratch. And it's no simple, unsprung, cookie cutter chopper frame either. We've already spent more than a 150 hours in the workshop and there are still small but important bits to fix. Lock stops: 3 hours, mounting bracket for rear lamp: 1 hour, moving and modifying kick stand: 4 hours! It's those final things that require determination.

So, if you've ever thought to yourself: "hm, maybe I should start a business building custom motorcycle frames", then think again. You will never make any money. Unless of course, you are prepared to build S&S engined choppers that look like PEZ-dispensers. But then again, you wouldn't be reading this if you were.

Sunday 5 July 2009

Radiator protectors.


As I mentioned in an earlier post, the backs of the radiators don't look particularly good. In fact: I wouldn't mind loosing the coolers altogether. But since I can't afford to change engines after every ride, they'll have to stay. Now, there are lots of motoX radiator protectors/braces out there, but they are all intended to protect the FRONTS of the coolers, not the backs, since the backs of the coolers are normally protected from your knees by the "radiator scoops". So, I've spent an evening making this drawing for some custom protectors. Tomorrow I'll try to find someone who can laser/water cut them for me. The perforated middle sections will form the backs of the finished items, and the solid sections will be bent 90 degrees and become the sides. When finished, they will receive a coat of, you guessed it, black paint.


Ugliest ever?


Is this the ugliest brake hanger ever? It might be. Well, it is a prototype. As I've mentioned before, we like to do a pig iron trial run before we put expensive aluminium billet in the mill. This time it turned out to be a good thing, since we, eh.. screwed up the measurements a bit. What is 220 mm divided by 2 now again, Indiana?:-)

If you've done this kind of thing yourself, you will by now have seen that we are going for a "hidden" brake hanger without a "strut" from from the brake caliper to the swingarm. Instead, the brake hanger itself is meant to take up the rotational force when the brake is applied, preventing the caliper from spinning around together with the disc. The tuning fork shaped part of the brake hanger sits inside of the swingarm and is held in place by a bolt, but can slide backwords and forwards with the axle when the wheel is adjusted to take up the slack in the chain. And yeah. We are going to make a nicer looking one. I promise.

Friday 3 July 2009

Need-to-know basis only.


Well, we finally hit a snag. On my original Husky motard, the back brake was mounted on top of the swingarm, but that position is now filled by the supporting structure for the shock mount. So, we tried to cut the old brake hanger, turn it over/flip it outside in and then re-weld the pieces together again. But to be honest, we made a bit of a hash of it. It looked shit, and the cast aluminum brake hanger didn't respond well to our TIG-torch (it melted). The problem with the original low rent Brembo caliper is that it's not easy to make a new hanger for it. The caliper is of the "floating" kind – it needs to be since it only pinches the disc from one side and thus needs to be able to move sideways – and is integrated with the hanger in a pretty complicated fashion. Hm. What to do? I didn't want to put a huge and ugly old caliper from a breakers yard on my lovely framer, and since I'm already over budget "Lookheed-Martin style", I thought: what the heck, let's see what the good people at ISR can provide... And here it is in all its beautifully machined, neutrally anodised glory. Good thing my wife has no idea what this little project has cost me so far... I'm relying on your discretion here:-)

Wednesday 1 July 2009

Coolers.


I am a very relieved man at the moment. The coolers fit! And it doesn't look crap either. When we sketched the geometry of the frame, we left some room for the coolers, but I had a suspicion that the coolers would prove problematic, since they are mounted a little lower now, than they were before. But it proved easy. I cut off two mounting eyelets from the old frame (I think it was the top mounting point for the shock), cleaned them up, drilled bigger holes, threaded a piece of 20 mm tubing through them and presto: we had a solid and rather "factory" looking main mounting point for coolers. It's the mounting point at the very centre of the image. There will be another mounting point in front of the coolers as well. That one sits a little bit higher up the down tube. There is ample room for the front wheel and the forks doesnt foul the coolers even at full lock. Result!

I am now doing some drawings for some sort of ventilated covers/protectors for the back of the coolers, since they sit rather exposed at the moment. I'll try to use the standard "fins" for the fronts.

Tuesday 30 June 2009

Front spindle


Freshly turned, hollowed out, stainless spindle with titanium end bolt. In the words of the Pet Detective: "I like it. I like it a lot!"

Oh, and BTW: the front wheel that Steve Lomas built, fit like a glove. No clearance issues. The spokes cleared the caliper by some 3 mm.



Monday 29 June 2009

Finally on wheels.


I won't make my deadline. I will not be able to finish this project in 180 days. There, I said it. It has taken quite a bit longer than I expected. Partly because it took much longer than I had expected to source some of the parts and because some parts were lost in the mail. And partly because I simply couldn't make up my mind about certain aspects of the bike. But mostly because this is the first time I've done a major project like this and since I've shown you my efforts here on this web page, I didn't want to make an ass of myself by building a dud. That said, I am really, really happy at the moment. We had the bike on wheels for the first time today, and I have to say that I think it looks OK. More than OK in fact. The proportions of the bike are very close to what I envisioned and the chassis looks compact and purposeful. The Husky engine is very compact (about half the size of a Harley engine) and I was afraid the bike would look wimpy and "empty" with the smaller motor, but it really doesn't. Now I can't wait to get the tank back and start the final assembly! One more month (or maybe two) to go!

Tuesday 23 June 2009

Rotaphilia, part 2.


I'm now back after wasting one week as an unpaid lifeguard in Mallorca (I have two small boys who both think they are Johnny Weismuller) and look what I've received in the post. Not bad eh? It's a Talon motocross hub, black anodized of course, a black Morad 3'' rim and a rather lovely 320 mm wavy disc from Braking, mounted to a black anodized spacer that the boys at Talon knocked up for me. I chose a 3'' wide rim, which is a little wider than the "standard" 2,5-2,75'' normally used for front wheels on flat trackers, since I have a theory that the Maxis tire will be less "squiggly" if it's mounted on a wider rim and therefore is flatter in profile. It will slow the steering down some, but I'm erring on the side of stability here (I'm an old fart after all).

The wheel was built by an excellent chap called Steve Lomas who not only is entirely pleasant to deal with, but also quick and thourough (I'm told he can ride a bit too). To boot, he has a good relationship with the people at Talon. Which is a good thing since nothing from their standard assortment of brake discs and sprockets would fit on my PM rear wheel. Steve called them, and custom made carriers are now in the works. If you want to get in contact with Steve, I'll be more than happy to supply his phone number. Thanks to the Sideburn-boys for the tip BTW.

One problem with the radial brake set up of the GSXR forks I'm using is that the calipes are pretty substantial and mounted in such a way that there is not very much space for the wheel spokes in between the calipers (the spokes of cast wheels are not dished). And to be honest, I'm not entirely sure that the wheel will fit, since I haven't had the time to test fit it yet... We've done the numbers, but we may have to shave off some material on the inside of the brake caliper to make it fit. Or perhaps get a slimmer caliper. More on that in a day or two.

Friday 12 June 2009

Gone swimming.

Next week I'll be on vacation, so no updates. The week after we we'll (hopefully) finish the assembly and I'll show you some images of the finished article (unpainted).

/D

Thursday 11 June 2009

Nice or bajs*?


Instead of clamping the remote spring load adjuster to one of the frame tubes, using a hose clamp, we came up with this little solution. We turned a little "plug" from stainless steel that fits into the top tube and drilled two holes for a little bracket that will hold the spring load adjuster just below the carbon fiber seat unit, parallel with the shock and within easy reach (there is no battery or anything down there remember). The four bolts will be replaced by bolts with countersunk heads for a really slick look and the plug will be obscured by the seat pad that will snuggle up to the top tube, just below the rear of the tank.

*bajs: Swedish for faeces.

Wednesday 10 June 2009

Frickin' lasers.


Maybe laser cutting is no longer the last word in high tech. But I still think it's pretty cool that you can cut solid steel, like these 3 mm plates, with a lamp (albeit a rather powerful lamp). And the word "laser" reminds me of a funny scene from Austin Powers:
Dr. Evil: "You know, I have one simple request. And that is to have sharks with frickin' laser beams attached to their heads!"
And besides: that's one less item on my to do list.

Assembly started!


We have now started to put all the bits together (bondo bucket tank and all), and to my relief, most things actually fit:-). At this point, it may look as if it's just a case of slapping on the wheels and go riding, but I can assure you that it's not. I have a to do-list that's half a mile long. The exhaust has to be modified, the seat mounted properly, the electrics... Another issue that remains is how to mount the coolers, and get the bump stops right so that the fork doesn't foul the coolers or the tank. I have a plan for how to do it, but sooner or later we are going to run into a big snag. Could this be it?

Monday 8 June 2009

Spacers.


The 2007 Suzuki GSX-R750, from which the fork tubes were lifted, had 310 mm discs up front. But since I will be using a 320 mm wave disc from Braking, I needed to lift the caliper 5 mm. Hence these spacers that will go between the caliper and the integral mounting studs on the fork bottom. At first I thought of this method as a bit of a bodge, but I've seen Superbike teams using spacers like these, so I guess I'm in good company.

Sunday 7 June 2009

Prototype yokes/triple trees.


As I've mentioned before, I haven't really got a comprehensive drawing for this bike. Just an overall plan and a mental image of what I want. I do some maths, ask a LOT of questions to a lot of people, and then we make a prototype. If the prototype turns out good, it ceases to be a prototype and becomes the "production item" and is welded/added to the bike. That way I can tell myself: "–never mind, it's only a prototype" when I screw up.

The triple trees, on the other hand, were always meant to be prototypes (honest). The aluminium blocks needed to machine a pair of chunky yokes are pretty expensive and we couldn't afford to do more than one run. So we put some scrap iron in the mill and did a trial run. The result is in the pictures. They look pretty good to me, but they weigh a ton and will be replaced as soon as we are sure that the geometry works out.

Friday 5 June 2009

DISAPPOINTED!


I got my tank back from the paint strippers today after it had been soaking in solvents for a couple of days. And it turns out is was a proper "bondo bucket". When I bought it, the seller told me, and I quote: "It has some ugly paint on it, but no dents, putty, or bondo". Yeah, right. Thanks a lot for that.

But since I don't have time to send it back and there is a waiting list for a new one, I went to a guy I heard of that was supposed to be a "wizard" with everything alu. He took a look at the tank, which to my eyes looked terrible, with easily 10 mm thick bondo in places, and said: "This is nothing, I've repaired tanks that looked much, much worse". He then proceded to show me a photo album of tanks that went from "crumpled up fag paper" to mirror smooth in his capable hands. "I'll cut a hole here, and here, smooth it out and reweld it again... No prob". Big sigh of relief from me. Not surprisingly, he had a waiting list, so this means I can't send the tank away for paint until the 25th of June. But I'll rather wait than ride around on something that might look OK, but with bondo festering underneath. On Sunday we'll attach the forks and get the bike on wheels. Stay tuned.

Monday 1 June 2009

Rotaphilia.


Is it wrong to get sexually aroused by a motorcycle wheel? My wife thinks it is. But then again, she hasn't been waiting for two months for this, to my eyes, absolutely stunning piece of hardware. I knew from the first time I saw one of these beauties that I wanted one for my project. "Seven sorrows and eight disappointments"* later, it is finally here.

Why Performance Machine stopped making these I will never understand. Unless people stopped buying them of course. Which I find incredible. I called PM's technical support to ask about the "pitch circle diameter" (it was "3 1/4 inch x 5" BTW) and the very helpful guy even congratulated me for picking up such a rare find:-) The fact that it doesn't accept any standard brake discs or sprockets, is merely something we have to work around. Once I get the wheel powder coated black and shod with a brand new Maxxis tire, I'm bringing it to bed with me.


*Swedish proverb

Sunday 31 May 2009

Steve McQueen rode a Husqvarna.


I got an unexpected gift this weekend from my youngest brother: a DVD of "On any Sunday" – a film I had seen excerpts from on Youtube but not in its entirety. I could hardly wait until the kids and the missus had gone to bed, before I poured myself a JR Ewing-sized bourbon and settled in for some cool seventies flat track action.

What I hadn't expected was that the movie is actually about almost all kinds of motorcycle racing, from road to ice racing. And I didn't expect Steve McQueen to feature so heavily, nor that he was such a good rider. I knew he raced cars, but not that he was a top amateur motocrosser. But perhaps what made me most excited of all, was the fact that the whole movie is a virtual Husqvarna love fest! There is a Husky in almost every scene (the flat track scenes excluded) and the shots of Steve McQueen doing some beach riding with his buddies on his red
1970 Husqvarna 400 (check out the actual bike here) in perfectly fitting jeans and sweater is some of the best motorcycling footage I've ever seen.

Much has been written about Steve McQueen driving his Mustang in the movie "Bullit". And while that car chase is certainly cool, the shots of McQueen wheelying and crashing that gorgeous Husqvarna in On Any Sunday is in a leauge of its own. Thanks again bro.

Friday 22 May 2009

Back from sandblasting.


Originally I had intended to paint the frame gloss black. But I have to tell you that it looks very nice in flat gray as well (it's not painted yet, the gray colour is the colour of the raw steel after sand blasting). I know the street tracker guru Richard Pollock of Mule Motorcycles paints a lot of his frames in a medium gray. Hm. Decisions, decisions.

Wednesday 13 May 2009

Boom, there it is!


Apart from a couple of brackets for cables and a few mounting points for the seat unit, ignition coil and the water coolers, the frame is now complete. The dark gray lower parts are what is left of the original frame and the lighter/shiny tubes are new. The round pieces of metal in the steering head is there to protect the bearing races now that the frame is sent off to be sand blasted in preparation for that all important M.O.T. and subsequent powder coating.

Next job on the list: machining the new fork yokes. Anyone need a pair of Gixxer yokes from a K7 GSXR750?


Rear end done.


Here is the finished rear frame viewed from behind. Admittedly the rear "loop" is a bit over engineered, since its only purpose in life is to prop up the upper part of the carbon fiber seat unit (and provide a bit of torsional rigidity to the rear frame). But I wanted it to look sturdy, in order to impress the M.O.T man, with whom I have a date in a couple of weeks. At first I had planned to cut off the two protruding pieces of tube (left and right lower corner), but they do a good job of supporting the rear part of the rather flimsy seat unit, so I think I'll keep them as they are. They won't be visible when the seat unit is in place anyway.

Tuesday 12 May 2009

Back end.


We are now truly on the home stretch with the frame. This is what the back end will look like. I know it looks as if the swingarm will hit the diagonal supports. But it won't. I hope...


A pretty good idea.


After some careful measurements and quite a bit of moving the swingarm up and down (to check clearances), this is how we decided the new anchoring plates for the shock mount should look. Don't knock good old cardboard when it comes to mocking up parts for your frame. To compensate for the decidedly old-tech approach, we'll send the actual plates away to be laser cut:-). One of the things I'm most satisfied with on the whole frame is the "adjustable" front shock mount (an idea I nicked from a C&J frame). I really recommend a similar design for anyone attempting to build a flat track frame of their own. Without it, moving the front anchoring point – to get the correct angle for the swingarm – would have been a huge hassle.

Wednesday 29 April 2009

Early mock-up


Never mind the wheel and its weedy front wheel cruiser tire (God willing, it will be replaced by a bona fide PM 8-spoke rear wheel with a proper, fat dirt track tire in the not too distant future). But we can at least see where this build is heading. I find these mock-up sessions invaluable when trying to get the frame just right. After this one, we decided to change the front anchoring point for the shock. The two plates holding the shock will be replaced by two nicer looking ones, moving the shock about 25-40 mm back and about 5-10 mm "up" which will make the swingarm droop a little bit more and increase the clearance between seat unit and tire. The back of the seat unit will come down about 15 mm.

And please: if you spot something stupid – speak now, or forever hold your peace...

Tuesday 28 April 2009

Summer's fast approaching.


The last week has been unseasonably balmy here in Sweden with temperatures hovering around the 17-20 degree mark (that's Centigrade) and the streets are already filled with bikes. Which of course makes me want to rush the project along. But I'd rather make it right than on time. So we keep on checking, and double-checking everything. The rear part of the frame is taking shape now and will be attached tonight. BTW: the transverse piece of tubing at the end of the rear structure will be omitted as soon as the "loop" that will hold the seat unit is welded in place. More pics tomorrow.

Thursday 23 April 2009

Sideburn Issue #3


If you are even remotely interested in flat tracking or motorcycling in general for that matter, you need to buy Sideburn – the coolest motorcycle magazine I've ever come across. And believe me, I've read most of 'em. Click here to go to Sideburns blog and then hit that Paypal-button. OK?

Monday 13 April 2009

Swingarm, part 4.


We are now some 70 days into the build, out of the allotted 180, and we have yet to encounter any major problems. I know I'm probably jinxing the whole thing by writing this, but I just want to share the good feeling I have at the moment.

The swingarm is almost done, and in a few weeks I'm going to have my "byggbesiktning", which is sort of a pre-MOT, that is conducted by an organisation called SFRO. The SFRO-inspector will check out the welds, materials used and measure all the angles to make sure that the bike will be road worthy when finished. If my bike passes this preliminary MOT, I can then go ahead and install the electrics, brakes and of course: paint the bike (Death Spray Custom: are you reading this?).