96 rm250

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11/25/2017 7:55 AM

hey all;
new to this forum,i just picked up a 96 rm250 with upgrades and extra parts pretty cheap. top end was off and was told piston skirt cracked off (which it was) and caused the engine to lockup,upon further inspection winds up the lower rod bearing must've been the culprit because there isn't any. iv'e read about the power valve,clutch(being on/off type) issues,however from much research i think the ol' girl is worth putting time and effort into.
i want to make it more for woods than mx and any advise would be greatly appreciated,i know i will never ride it to it's full potential, i weigh 145 full race gear on so if the bike is a little low on torque that won't be a problem.
i believe the bike was raced at one time because this what i got;
wer steering stabilizer
applied upper triple clamp
gold fatty bars
extra capacity fuel tank ( i don't know if it's a clark,ims or maier) and stock tank
larger radiators,werks guards,carbon engine skid,carbon pipe protector
4 fmf gold pipes ( gnarly,fatboy,and 2 fatty's) turbine, and a powercore silencers.
vforce carbon reeds,barnett basket,fmf pressure plate.
hygear tuned shock,so i'm believing that the forks where revalved also.
a bunch of radiator scoops,fenders,side plates.
stock 38 pj,165 main,50 pilot,stock needle 2nd down from top,air screw 1/2 tun out.
no porting, cylinder measured 66.42 1 inch from top.
extra trans gear set( 3rd gear drive and driven busted).
brand new artrax tires(i know they're not the best)
and other misc stuff.
the piston was a namara, but i'm not sure which one to replace it with or if i have to get the cylinder replated first.
i used to get wiseco's for my trx250r but they were steel liners.

sorry for long post, thanks,max


11/25/2017 10:09 AM

A few suggestions i can offer on that motorcycle, if the cylinder is still plated (but possibly a bit worn)go with the fractional larger sized pro x piston. While you have the cases split for crank removal take a very good look over all the tranny gears. Be sure to also replace ALL the parts associated with the internal water pump. It would be a shame to put everything back together and have the pump seal drip or weep only after a few hours. The clutch issues are impossible to ignore. You can spend your way out of this or you can learn to deal with the poor engagement. Even with all new fancy billet clutch parts the poor clutch action returns pretty quickly. Another thing to look at is how the cdi box is mounted behind the number plate. Be sure that the foam isolation/vibration pad is not worn thru. This can cause a shortened life span of the box itself. Hope this helps.


11/25/2017 3:27 PM

thanks for the reply godog
the water pump and cdi where something i didn't know about, that is something i will definitely look into.
is there any particular type of clutch fibers or gear oil that would help?


11/25/2017 10:13 PM

Back in 96 I recall using Kawasaki fibers and steels from which years of kx I can't remember....I think that from 89 to 99 the plates were all the same tho....again not to sound bias but you can't go wrong with pro x brand clutch plates. As for oil.....I don't want to open that can of worms about which is superior but if you change it very regularly a good non synthetic ATF will offer the best clutch feel.


11/26/2017 11:05 AM

rcmax64 wrote:

hey all;
new to this forum,i just picked up a 96 rm250 with upgrades and extra parts pretty cheap. top end was off and was ...more

Sounds like you got quite a bit with the bike. A good friend of mine raced against me for several years in CRA harescramble competition on a 1997 RM250. He may be able to help you out with setup and mechanical issues for those bikes. If you contact me via Facebook Messenger, or IG I can put you in touch with him


Many thanks to everyone helping me out this GNCC season: SRT Offroad, Acerbis, FCR Suspension, O'Neal Racing, Evans Waterless Coolants, Rekluse, Twin Air, Braking Brakes, Carbsport

Profile image credit Ken Hill Photography

11/27/2017 3:19 AM

thanks harescrambled;
i'll do that.


11/27/2017 10:33 AM

If the cylinder is worn have the nicasil re-coated, sleeves are a poor alternative.

Avoid Namura pistons like a bad case of herpes. Lousy quality and even worse customer service.

Eric Gorr's book suggests using a Hinson basket and pressure plate along with KX plates and springs.
Kawi P/N's: fiber 13088-1105, metal plates 13089-1066, springs 92144-1351


11/27/2017 5:39 PM

Just something to add. I raced Suzukis the whole 90s...and despite what MXA said I never spent the money on those Hinson clutch parts. I found that the problem was always the inner basket would get deep notches wore in it. I could replace it once or twice a year for 50 bucks. I do remember using the KX plates.

I remember some powervalve issues on some of these 250s but can't remember what....I never had any problem.


11/28/2017 3:06 AM

thanks for the replies matt & wpark,
the cylinder looks good, no gouges or scratches, the cross hatching is visible (but barely) but there isn't any wear through or ridge at the top,the piston is a namara (now a paper weight) i think the po put in an "a" sized piston which caused the destruction, i can see where there was chattering marks on the piston from rocking in the cylinder. how the po couldn't hear that is beyond me.


12/2/2017 3:16 AM

i was wondering if i can get some advise on what size piston i need for this bike, i've read about the letter designation and understand the reasoning behind it, i found letters (NND3) stamped next to the exhaust port on the lower right that would indicate the bore size should be 66.37, is this correct? the only other numbers i found is (2502r) stamped on the left side of the cylinder just in front of the forward mounting hole. the cylinder doesn't have port work done to it,the power valve is the steel single slide style so i know it's a 96.
thanks, max