87 250r issues

[SHOWTIME]

Originally Posted by climb any hill

That's alot of carbon buildup on the piston but not bad. You might of been running rich but then lean when the reed broke and sucked more air in.
And that's prob why that plug doesn't show fouled. Get that new top end kit from RJATV.

i don't mean to be rude but climbs post is the only one
in this entire thread that makes any sense. Yes the piston
is toast DO NOT REUSE IT. Do a fresh hone on the cylinder
and as previously stated, order the new kit from RJATV...cant
beat the price. I agree with climb, the bike was running to lean
before the reeds broke, the discoloration is due to excessive burn.
The broken reeds will make it run too rich which is why the plugs
keep fouling out. I also would say that one of the gaskets had
a small leak. im sure you were loseing a TON of compression
with the piston like it is.

[Lucky13]

Thanks Show for clearing that up. kinda seemed like a lotta mixed answers... I'll definitely be looking into the kit from RJ. But, I might just have the guy back home thats going to do all the top end work order the appropriate kit for it so I don't have to separetly ship that to him. Cuz I imagine he'd want to make sure the bore fits the piston properly...right?


The strangest thing is that I have not lost any compression. The only reason I opened everything up was because I was starting to foul plugs and had no idea the reed was broken. I even let someone ride it this weekend that had ridden it when I bought it and the plug fouling was there only complaint as well.

[fulltiltrider]

Yes, he will want the piston to properly measure the bore. I dont know, to me it doesnt look to have been running lean by the markings on the piston. But then again I've never burnd one up before lol. Ive had a piston shatter on the exhaust side before from a ring getting hung up, but thats the only experience I've had in that sence. I've seen pistons that melted on the exhaust side but that usually melts right over the ring causing you to lose all compression.