Finally, some real progress on the XR250R. I haven't written much about it but I've been steadily working on it and made some interesting discoveries.
The intermittant spark problem seems to have been cured by a new CDI unit, found on eBay for under $50.
The forks were a stumbling block for me, I was able to get one apart, but not the other. So I installed new bushings in the one that I got apart and proceeded to put it back together. That's when I made the most interesting discovery...pictured below.
It's a homemade PVC spacer for the springs, presumably for shorter/stiffer springs, thus the need for a spacer to take up the slack. There is one for each fork, but only one had the writing that identifies them as being installed by J. Cyr, that would be Jean Paul Cyr, Matt's brother. I called Matt as soon as I saw that and we shared some laughs about it. This bike originally belonged to Norm, Matt's dad, who then sold it to Jean Paul. Between the two of them this bike has seen some tough duty.
Anyway, when I put the fork back together it was 1 1/2" longer than the one I hadn't taken apart. This puzzled me greatly, and after several attempts at re-assembling it, all with the same result, I finally got some further insight from Seamus. He looked at it for a few minutes and decreed that I must have misplaced another spacer that would have reduced the stroke. The solution therefore was to make a new spacer, and now I know where the spacer goes to make the stroke shorter on a conventional fork. I was so exited I forgot to take a picture before I put it together.
Once I had all that back together I fired it up and rode it around, but after a short time I noticed smoke coming from the front brake. Looong story short, I rebuilt the caliper, put new pads in, bled the system, and now we have a working front hydraulic disc brake! Oh, and I swapped out the ancient front tire and tube with less ancient ones while I had the front wheel off.
Here are some comparison pics of the '87 XR250R vs the '82 XR200R. The forks and front wheel on the XR200 came off an '82 CR125, which was a motocross bike. I might try to shorten them.
A ride report on the XR250 will be coming shortly. I've ridden it around the lawn, and Hannah ripped around on it as well.