FZR/XR650R Build Thread....... It's Alive!

[pefrey]

Also, what material did you use for the chain slider?

[tgold]

Acetal

[tgold]

I haven't done much to the bike since I rode it on the track in September and I figured I'd better get going on it before December turns into March! I have an FZR400RR swingarm that I was going to put on the bike so that I could put a 5.5" wheel on so that I could use proper 250 GP bike tires, but I'm thinking that it'll require too much modification that I don't really have time for. Sooo, I decided to keep the current Deltabox swingarm and make sure the 4.5" wheel is properly centered and use 160 width tires. I think that my current spacers are causing the wheel just a few mm off center and that in turn causes one side of the tire to be too close to the swingarm for me to use my tire warmers. There's a little bit of play in the suspension linkage, so while I have the swingarm off, I'm going to replace all of the suspension linkage bearings, bolts, and collars. Since some of the parts are no longer available from Yamaha, I decided that I'm going to source them myself. I'll post all of the sources, part numbers, etc as I figure that out. Engine-wise, I decided that I'm going to be fairly conservative and install a Falicon rod and have the crank trued and welded, throw a hi-compression piston in the stock bore, and maybe a more aggressive cam.
So I may be sticking the FZR400RR swingarm up for sale soon if anyone is interested.

[Evilchicken0]

The standard FZR400RR rear wheel is 4.5' using a 160 profile tyre, I'm not sure a 5.5 with a wider tyre would fit

[tgold]

There's definitely more room than the "standard" Deltabox swingarm and I think a 5.5 wheel with 250gp rubber would work ok. But I'm just sticking with what I've got on there now anyway.

[dash]

I just wanted to say that this is one of my favorite posts for aspiring bike builders, and it deserved to be mentioned for people that haven't had the thrill of reading through it. It is a good study in design, fabrication, and innovation. It gets an A in my book!

P.S. - For those that keep up with it, we love the updates!

[tgold]

Well, time to bring this thread back from the dead......

Since doing the track sessions on the XR, I disassembled the bike to make further modifications and I really didn't get any further. In the meantime I spent the 2016 race season endurance racing a 250 Ninja and had a blast. For various reasons I was no longer interested in continuing to develop the XR650R motor in my fzr400 chassis and I decided to put a Yamaha R3 engine in the bike in order to build a sub-280lb endurance racer.
So with that in mind I sourced an R3 engine to begin the build. I'm currently working on locating the R3 motor in the chassis, but before I do that I have to install the Kawasaki 300 Ninja wheels and center them so I can make the proper wheel spacers. That will allow me to align the front and rear sprockets. Then the design and fabbing of the motor mounts can take place.

Pics will be coming........