Vintage 250R race ported cylinder questions. Chuck E. Racing, Pro National.

[PLJ.]

I have had this cylinder for a long time, 1990 or 91. Was wondering if there is any hope of a repair, as there are many technical gurus here on the forum. This is an 88-89 250R Chuck E. Pro National. Was told way back then that it was the same as Dentons that Chuck put together that year he ran his stuff, max allowed overbore CC, etc. Could be bs, but it was a good story. Couldn't live without it, but my problem was I had a very good, low hour 86. Was sent out to Varner I believe and the bottom of the cylinder was decked, the head modded, a new sleeve punched in, bored and sent back with a custom modified skirt prox yz piston. Little tough to jet, but with a Paul Turner National, Fat boy and a 38mm PJ the thing was a rocket! Anyhow, sleeve broke at the very thin intake bridge. Looking closer appears like the upright bridges were ported beyond integrity, possibly cracked and this cc configuration runs the sleeve thinned out to the max. I have lost this piece in two sleeves. Would there be enough piston skirt support if these bridges were removed? Or is this a paper weight now? Any info would be greatly, has anyone ever run one of these? Thanks

[ironchop]

If I'm understanding you correctly.....

It's not the piston skirt cracking from lack of support I would worry about if you removed those intake bridges. Your piston rings may open up too much inside that intake port without those bridges and clip or snag the upper and lower edges of the sleeve on it's way past the intake port.

As far as it being a paperweight, I doubt that. I'm sure if you wanted to, you could have someone add more material to those bridges by welding them up and then thin them back down but not quite as much as they were before. The aluminum bridge is probably cracked too if the sleeve keeps cracking there but that can be welded too, I'm sure

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[El Camexican]

Call Mark at Kustom Kraft. He may be able to fix it.

[Joseph Farrow]

If it is a Chuck E Racing cylinder. It Should fly. It would be worth the effort to have it fixed. Chuck Edwards built some fast 250r's.

[deathman53]

I have a curtis sparks national mx ported 88/89 cylinder and modded head. It has a crack on one of the intake bridges, I was told by 3 places that, its a paperweight now. You might be able to fix the cylinder, but you will never get it re-sleeved and retain the same porting exactly and it will just break again.

[NeverLift]

Have John Tice make a custom sleeve.
http://www.3wheelerworld.com/showthr...ghlight=sleeve

[Billy Golightly]

I had a later model R cylinder that had one intake bridge get a crack in the sleeve, and into the casting. I just cut a ramp for the ring to pass over without touching the crack and ran it a few years. Your mileage may vary.