Friday 27 February 2009

Colours, colours.


I know it's a little bit premature, but I've already started thinking about how I'm going to paint my tracker. Or rather; how I'm going to have it painted. I've done some tests in Photoshop (the best app to ever take up space on a hard drive). The look I'm after is best described as "retro-racing". Sort of a mix between the legendary 1970's Gulf Porsche livery and 80's Nascar. At the moment I'm leaning towards using the old school Huskvarna ruby red as a base colour, but with some metal flake mixed in, combined with white and black sections (a bit like no 3 in the picture above). The wheels – If I ever get them – will be powder coated gloss black, and the frame satin black. At first I was going for a more modern "Husky factory" paint scheme, since I normally don't like retro, which I think is a cop out for designers too lazy to come up with something original (read: J Mays). But the shape of the tank and seat section doesn't really lend itself to anything too modern. Then again, I might change my mind before it's time to send the "tins" away for paint.

Thursday 26 February 2009

Rant. Continued.

Two weeks ago, I wrote about how I thought that USPS had lost a wheel that was on its way to me from Philadelphia. Well, now it's official. They've lost it. Fair enough, mistakes happen. Human error and all that. But what really p-----s me off, is the fact that they need 17 days to look for it. Yes, you read correctly, seventeen DAYS. "– You mean 17 HOURS?" I retorted with a chuckle. But no.

I just can't see what they are going to do for 17 whole days. Are they going to hire an investigator to manually rummage through all the airports/harbors/warehouses used by USPS? No I don't think so either.

I'm the part owner of a small business here in Sweden and we ship stuff from Finland using Schenker, and they pretty much suck as well, but USPS's customer service takes the cake.

Tank.


When I first started thinking about this project, I made a little budget and started checking prices for components I knew I would need. So I checked Storz's webpage and found that an aluminum "XR750-style" tank (I think they are manufactured by a company called RaceTech) would cost $200. Fine, that sounded very reasonable. Two weeks later I was going to order it and realized that I had misunderstood. It wasn't $200, but rather $820. Without petcock. Bugger. So I started to look for a used one. After a few weeks of advertising on the excellent, and free, www.vft.org, I got an email from a very pleasant gentleman from MacDaddyRacing who had a spare one for sale for $500. A deal was struck.

I don't know what possessed the airbrush artist to paint that heart/vulture-thingy on it. Let me just say that it wont look like that when I'm finished with it.

Tuesday 24 February 2009

Word of the day: "scalene"


A scalene triangle is a triangle where all sides and internal angles are different from one another [thank you Wiki]. A triangular arrangement like the one in the picture (which when I look closer is not actually a triangle... Oh well) is also a good way of strengthening the head stock area. It is also a must if you want to get your frame through a Swedish M.O.T.

XR750 frames use the space between the pipes as an oil tank, but since I don't need an external oil tank for my Husky engine we won't bother welding plates on the sides of our little triangle. It will be plenty strong anyway.




Test assembly.


The three shiny tubes in the picture replaces the curved "back-bone" tube of the original frame (see earlier post here). The cantilevered shock will pass between then two vertical tubes on its way from the swingarm to the anchor point underneath the top tube. We are still in the test fitting stage and the vertical tubes are not tack welded yet. In fact, the tubes in the picture will be discarded, as we aren't satisfied with how they interface with the top tube.

The shiny, short piece of tubing between the two yellow chain rollers is the start of the new swingarm. We are using the old axle and since the tire we're using is roughly the same width of the super moto tire it replaces, there is no need to muck about with the chain line or anything like that.

The bracket attaching the frame to our sturdy metal table, is where the old shock linkage used to be mounted. Since we aren't going to use it, we'll cut the bracket off once we're done with the welding. But for now it provides a very convenient way of keeping everything straight and secure.


Monday 16 February 2009

Gone skiing.

I'm in the Swedish "Alps" (think: molehills) this week. But if I don't freeze my ass off, there will be a major update next week.

Friday 13 February 2009

Theft/flattery.


Most flat trackers I've seen have been sporting a swingarm made from rectangular "tubing". And while that is probably the easiest and best solution, and probably the stiffest and lightest as well, I can't help but think that round tubing looks better. Just have a look at the picture to the right. That is the back end of the "NCR MIKE HAILWOOD* TT" (more pictures here). Isn't that the best looking rear end/swingarm you've ever seen? I hope the guys at NCR won't be too cross if I, er, borrow their design for my street tracker. Mine will of course be a cantilever design, so we will add the tubing on top of the main tubes for the monoshock mount. The new swingarm will be bit shorter than the one it replaces, since there is no longer any linkage in front of the rear wheel.

Wednesday 11 February 2009

Rant.

If you, like me, are going to assemble a bike from parts mainly sourced in the US, what ever you do, don't let the seller send you the parts using United States Postal Service (not to be mistaken for United Parcel Service). It takes FOREVER! I ordered a wheel January 22 and I still haven't got it. It's 2009 fer chrissakes! Furthermore, their useless "tracking" service on their web page only gives me the info that "the package left United States from FOREIGN CENTERJERSEY CITY NJ 099 at 5:32 PM on January 28". So? What am I to do with that info? Unconfirmed rumors have it that my wheel is abord this vessel now making its way across the Atlantic, after having spent one week on the back of a yak from Philadelphia to New Jersey.

Tuesday 10 February 2009

Wheels of [mis]fortune


Oddly enough, the question of what wheels to use has been the hardest nut to crack so far. The thing is, no modern bike uses 19 inch rims any more. At least not at the back. The only cast 19-inchers I could find are the ones made by Performance Machine, but they are just too much "bling" for my taste. You could of course have a couple of motocross hubs laced to a set of 19 inch rims and be done with it. But I wanted cast wheels. So I started to look for 19-inchers. Someone told me that the rims on the Buell Blast (see earlier post) were "Morris" wheels, and that similar wheels had been used on 80s Kawasakis. It didn't take me long to find a suitable pair on eBay (see image above) and a "buy-it-now" deal was made. However, the jerk that had put the wheels up for auction, didn't pull them off eBay, and they were subsequently sold to another bidder. Hm. After sulking for a few hours, I realised that I hadn't really thought the wheel issue through enough. Not only was the Kawasaki front wheel only 1.85'' wide, which is a bit too narrow. The rear wheel, being an 18-incher, would have left me with a very narrow selection as far as tires go. In fact, the only 18 inch flat tracker tire available is the Dunlop K180, which is only 120/90. A bit too narrow for my taste. So maybe the fact that I lost that auction turned out to be a good thing after all.

To make things even more complicated, the only street legal flat track tire available is the 19'' Dunlop K180 front tire. There is no street legal 19 inch REAR tire as far as I know. But I've decided to go for a 19 inch rear rim anyway. I will have to find some kind of street legal 19 inch tire and slap that on when I go for the MOT. Maybe some kind of street legal enduro/touring-tire. Which of course will be changed for a proper flat track tire five minutes after the bike passes the MOT.

Sooo, what rims have I settled for? Well, all I can say is that there is one very promising rim making its way over the Atlantic as I write this. And it was manufactured in 1976! Check back in a couple of days and I'll show you what it is.

Sunday 8 February 2009

90-60-90

If you are building your own flat tracker, you need some measurements. These are the ones we're aiming for - measurements that have been collected from several sources and different kinds of flat trackers.

Wheelbase: 1375 mm

Ground clearance (height to centre of bottom frame rails): 200 mm
Seat height: 800 mm
Swingarm, from centre of pivot to centre of rear wheel spindle: 500 mm
Rake: 27 degrees
Fork offset: 60 mm
Ground trail: about 110 mm

There are of course many ways to skin a cat, but these measurements can at least be used as a starting point.

Friday 6 February 2009

Old school.


Husqvarna is a veeery old brand. It's been around since 1689 (yup, that's 320 years) and has been making bikes since 1903 (the same year that Harley Davidson was founded). Over the years the Husky logotype has changed again and again. I believe the above stickers are from a 1960's moped of some sort. I found them on the web and I might use them, depending on what colour scheme I decide to go for. They are silver underneath the protective tissue. Might look good on a dark background. Black perhaps:-)


Thursday 5 February 2009

Are you getting enough fiber?


One of the most distinguishing features of a flat/street tracker is the seat unit (along with the big wheels and wide handlebars). The traditional flat tracker seat unit comes in many flavours, but personally I prefer the XR750-styled one. There are lots of people cranking out these babies, like Storz. Most are made from fiberglass, but it's also available in higher spec carbon fiber. I decided on a seat unit from a Czech company called pro-carbon. It cost 234 € including postage and it was delivered promptly to my doorstep. Not cheap, but not too expensive either, considering the quality. It is incredibly light. Now I only have to resist the urge to leave it unpainted:-)

Steering head.


And this is how the steering head turned out after about 90% of the metal was removed from that huge metal ingot (see below). It now houses the new bearing races, and mates perfectly with the steering stem of the GSX-R750 K7 forks. Nice huh?

Wednesday 4 February 2009

Slowly but surely.


After much agonizing and after asking lots of questions to a lot of people (thanks Jan W, Ben, Gary et al) I finally decided on a 27 degree steering head angle (also known as rake). However, (and this is very counter-intuitive to me) the rake has little influence on how the bike steers. That is decided by the "ground trail". Ground trail is defined as "the distance the contact patch of the front tire lags behind the point where the steering axis intercepts the ground". The longer the trail, the more stable/slower your bike will steer. I'm aiming for 100-110 mm ground trail, which will keep the Swedish authorities happy. They won't pass anything with too little trail. Anoraks can read more on the subject here.

After that it was mostly a case of making sure that the front wheel would fit in front of the downtube, and that there was room for the radiators. I know the slope of the top tube looks weird, but in order to get the tank to sit correctly it has to look like that. The next piece of tubing to be added will be an almost horizontal tube tarting from where the downtube meets the steering head and going back - completing the triangular structure that will keep the steering head in check (and which will be mostly hidden by the tank).

Tuesday 3 February 2009

Forks.


I knew from the start of the build that I wanted a radially mounted front brake. Not because it was needed, since the bike will be pretty light, but because it just looks more "factory" without a mounting adaptor between the fork leg and the caliper. That ruled out the "standard" R6 right-side-up forks that are very popular among flat trackers, since they don't accept a radial caliper. After measuring quite a few modern upside-down forks I found that those mounted on modern Suzukis are a little bit taller than most, and crucially: they are available with a black coating on the fork tubes (I like black). After a couple of days of watching eBay, a perfect pair from a 2007 GSX-R 750 showed up on the US eBay. The price was very reasonable and when the UPS-man dropped them off at my door, they turned out to be just like advertised: MINT! I purchased a new set of bearings/races and had the new steering head (see last post) milled to accept the new upper and lower races. I will probably have to revalve or tune the forks to suit the lower weight of my bike. And machine new yokes/triple clamps to get the ground trail just right. But more on that later.

Monday 2 February 2009

Is there anybody out there?


No, it's not a left over section from Saddam's super gun. That huge lump of metal will turn into a steering head in the hands of my new best friend "Indiana Jensen" – a really skilled, local fabricator that I came across by chance, after giving up on sourcing a frame from the states. I wrote to every firm I could find that manufactures or sells frames for flat trackers, but no one was interested. Most didn't even bother to answer my emails. The rest were luke warm at best. Go figure.

A Husky 570 with 1722 km on the clock.

As it happened, I had a 2001 Husky 570 super moto collecting dust in my garage. A bike on which I'd managed to clock up some impressive mileage. 1722 km to be exact. That's about 1070 miles for those of you algebraically challenged. I'd had it since new, and a couple of years ago I had the lump blue-printed by the no 1 Husky-guru "Halvards". And since it's kick start only, it seemed like the perfect donor engine for a super simple flat/dirt tracker. No need for a battery and the wiring loom is super simple. It wasn't long before most of the bike was up for sale on "Blocket", the Swedish equivalent of eBay.

Rather than building a completely new frame, I decided to keep the bottom part of the frame cradle, which apart from looking quite alright, would make the whole swingarm-engine-frame interface a whole lot easier to handle. The picture shows what I kept and where we cut the frame up. Incidentally, a whole host of people emailed me, wanting to buy the "title" for the now non-existing bike. That is how stolen bikes get new identities and are sold as legit bikes, if you haven't grasped that already. No sale.

This is what started it all.


I'm not sure where I first saw this image, but I remember sitting for hours just staring at it. Talk about form follows function. There is nothing on this bike that doesn't serve a purpose. No chromed crap and no CNC:d bling bling. And those wheels... After googling furiously for the rest of the night, I finally found out that it's a C&J racing, purpose built "framer" with a Buell Blast engine and Morris magnesium wheels. That it was assembled by Sundance of Japan, and that a similar one would cost in excess of $20.000. Hm... There must be a cheaper way, I heard a little voice in my head saying. Well, that assumption is still to be proved wrong, I console myself as I hit yet another "Buy it now"-button on eBay.

Gentlemen, start your angle grinders!

Here we go.

Over the next couple of months, I'll be sharing (cause sharing is caring) my experiences while turning my run of the mill Husqvarna SMR 570 into a "street tracker". If you have similar plans or just want to ask something, I'll do my very best to answer your questions.