I got a bit of tinkering done during the holiday break. Made a couple Top Hat spacers so that the RMZ Fork would accept the bw200 front axle. The unthreaded end will be split so that it will clamp the axle. The threaded end will not be split, but held in place with the pinch bolts on the fork.
While I was down in Georgia for Christmas I found a front-wheel from an ATC 250R for sale about 40 minutes away for $40. It is an 11 by 6.5 wheel which I will run on the rear. It is funny how close the gold anodized finish is between the Honda and Yamaha wheel.
I ordered a front and rear tire off of Amazon. The rear is a 24 X 10 R11 and the front that I ordered is a 27x 9 R12. The rear mounted up just fine but it became pretty obvious that the front was going to be far too big and bulky for the project. I made a trip up to Iron Pony and picked up a 25 x 8 R 12 swamp Lite for the front, which seems to be a favorite pick by the bw200 guys. It took some finagling with ratchet straps and some starting fluid to get it Seated on the rim.
Rear.
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Front.
I made up a quick tear hub, swing arm and triple trees from wood just to do a bit of mockup.
The forks are a little bit on the long side so I will probably have to use a combination of internal lowering and sliding them up a bit in the triples to get everything where I need it to sit, but overall it is fairly close. The swingarm looks a little bit long in the mock-up but it is only an inch longer than the stock xr400 swing arm , and I have to leave myself enough room to build a jackshaft in front of the wheel yet keep it far enough back that my foot won't be into it.