350x Topend on 300ex?

[PolarisRider]

Will a 350x top end and a 350x piston bolt on to a 300ex bottom end and crank as long as I bore my cases?

[MXQUAD294]

Call TC Racing. I know he put a 350X head on a 250X motor. Not sure about the cylinder. I think he used the 250X cylinder.

[bwamos]

I think you are correct. I remember those were some pretty nasty setups (for the time).

[PolarisRider]

I dunno, I just think that would be a good idea for a 350 kit. I know the cases need bored but I dont see why the other stuff shouldnt work. Maybe a longer timing chain.

[motoboy66]

Yes it will fit. I know of one that has raced that way since the mid 90's. I am not sure what else was done, but the 350 head flows better. It was one fase 300!

[sparks427]

but what about the cylinder and piston, do they fit?

[bwamos]

Originally posted by sparks427
but what about the cylinder and piston, do they fit?

I highly doubt it.

[hittherevlimit]

when you call tom, ask him about jeremy schells 400, it was a bike he built for jeremy "the hick" schell.

it was a laeger framed, 250x, bored and stroked to 400 with a 350x head. it was the first 4-stroke to ever compete in the pro class with the 250rs. it was around 1998-1999 that it was built, and the last time i talked to tom about it, pieces of it were still in the national circuit.

i had a chance to buy it in like 00 or 01 for $9500! man i wish i had the money, that was my fav. bike ever!

TC Racing 814-723-3514



Eric

[MXQUAD294]

Schell's old bike is the one I was referring to that Tom put the 350X head on. That bike was sweet. Tom is very creative and can flat out make a 4-stroke fly. TC all the way!!!

[sparks427]

right on, but how reliable would a 400cc bore in a 300 or 250 cylinder really be? thats alot of bore for that little cylcinder.

[MXQUAD294]

Probably not that reliable for someone that doesn't have TC rebuilding the motor after every race. A bike like that would have to be maintained meticulously or it would likey grenade. Thats the beauty of being a pro rider with a mechanic.

[ZSNOW]

anyone got pics of that quad? sounds sick!

[MXQUAD294]

There was a complete story on it and the Sparks 300EX that Harold Goodman rode in the 4 stroke Pro-Am class in an old magazine. It was during the time all of the hybrid 4-strokes were coming out. The article had interviews with Tom, Jeremy, Harold, Curtis, and Dave Diver (if I remember correctly). If I can locate it (I'm a magazine pack rat), I'll try to scan it and post it. It will probably take me a while. Do some Google searching, you might be able to find it online somewhere.

[ZSNOW]

250r/250x jeremy schell hybrd

[hittherevlimit]

IIRC when i talked to tom, it had a continual oil consumption issue, and i think the hick had it sieze on him once or twice.

if your seriously considering having tom do it, call him and he will tell you all about it. the man likes to talk about stuff like that, the last time i was there i couldnt leave, we chatted for like 2 1/2 hours about cool **** like that.

he is one very intelligent man, and has seen it all in this sport.


BTW, the one posted above wasnt the one i was referring to, the bike i was talking about was a blue and chrome laeger, with white 250x/300ex plastic. i think it was a rocky ridge racing bike IIRC.



Eric