Rm 250 top end advice..

[Jaguars7129]

Hello, I am doing a complete engine rebuild on my 1984 rm 250..My question is about the top end..I measured bore it and it is 2.765 inches. The bores wear limit in my clymer manual says it should be no more than 2.6875..Is this too much and will it have a significant impact on engine performance or engine life..I am not racing the bike, but i still want a bike that will throw me around pretty good in the trails..I was just planning on throwing in a standard wiseco and riding it as is..any adivice on what i should do is much appreciated..thanks..

 

[6pac]

Hi mate
My advise would be to get the cylinder re bored & fit an over sized piston.
If you run a standard size piston in that bore its likely to snap a skirt.
(The piston slaps around at the end of the stroke & eventually fails)