All - thanks for the responses. Great site, I'm learning a lot.
Gowen - I agree, those are all excellent choices of learner bikes. But my kid seems to have inherited my need to forge along a path quite separate from the mainstream. We've talked a lot about it, and he's adamant that he's going to ride a 2 stroke. I think a lot of it is due to his friends and their KLX110s and CRF150s, and how heavy the bikes feel at low speeds. And part of it is, I figure by now I should be able to pull this off and build him a ridable bike.
Interesting point about porting, I've been thinking about that. I realize it's hard to do better than the factories when it comes to porting, but in this case, I actually want to do worse - which doesn't sound all that hard! If I could get a cylinder cheap, I'd be willing to try to open the ports a half mm or even 1 mm earlier, trying to get a bit more torque at the expense of peak power. Then after he's gotten a bit of experience, the stock cylinder could go back on. We may try that, I'm watching Ebay for parts.
re: flywheel weight, I checked the steahly and the sfb sites, they don't make anything for KX85s (or KX500s). But from looking at their pictures, a flywheel weight seems little more than a stainless steel disc which is easy to mount. Obviously have to be machined, if it isn't centered that'd lead to a lot of vibration. But at first glance, it looks doable. WHat am I missing?
re: reed spacers - is there a source for such?
re: timing - another interesing idea. have to figure out how to avoid detonation.
thanks for the tips.
Alan - turning 60 on a KX5 (which is cool) - you win, you got me by about a decade.
I found the site thru a google search for KX85 flywheel weights, it lead me to an old post. saw what was happening, figured I better join up and check out the site carefully.
Hughes - thanks, glad to be here.
I better get back to digging thru the old posts.
regards,
kaos