rm250 rebuild

[rmrider45]

took apart the 250 due to the fact it was hard starting and had a low compression test. the inside of the cylinder looks like new not a scratch. piston that was inside was a WISECO 642M06700 and looks good also which is standard bore of 67.00mm ..but the rings seem to be sloppy . out of the 2 rings if i put it in the cylinder seems sloppy .here is my ? if i put a new top end /piston/rings /etc/.will i be ok .i did put a magnet indide and it does stick so i would say its a Cylinder Sleeve. just dont want to put this back together and in a week it wont run .. strange how the rings went bad ..piston /Cylinder/head /look real good compared to most i have took apart over the years..i do have digi micromerter. do i need special tool to check for ring end gap. one ring in opening when in cylinder almost touches .the other ring has much more of a gap .. thx for any info.. :ride: :ride: :ride:

 

[arnego2]

Sleeves wear more than plating, maybe plating the sleeve would be a great idea if that is not what you got there on your cylinder. So far I know there is a tollerance allowed in the ring gap.

 

[rmrider45]

what about Measuring the inside of the cylinder top and bottom will that tell me if i need replating?

 

[IndyMX]

you measure ring end gap with a feeler gauge, and on the old rings, don't bother, they're worn out.. Measure the new rings to make sure they don't bind when installed.

 

[EncyclopediaRonnie]

if its been sleeved it will chew rings faster than a coated bore. measure up the bore piston and old rings.

if it is sleeved and its out of the tollerance you can fit a overbore verry easily as its a steel sleeve, if its coated and in good nick a mega light hone to take the glaze of and a new piston and rings and shes good again. the hard starting is more likely reeds id say get some pics of your bore up for us to see