Messages

1

Technical / 02 RM 250 Cylinder/rod/crank issue

« on: November 30, 2012, 05:40:55 AM »

Turns out the skirt in the intake side of the piston was contacting the cases at the bottom of the stroke. After filing it down I have no interference. Hopefully it doesn't blow up but only one way to find out. Note to self: never buy another Namura piston. Cheap isn't always good. Never had a single problem out of a wiseco so that's what ill stick with from now on.

2

Technical / 02 RM 250 Cylinder/rod/crank issue

« on: November 29, 2012, 04:47:17 PM »

Purchased the bike seized. Tore it down. Piston broke and locked it up. New bottom end, replayed cylinder, new top end. While putting the top end on I had problems. Lubricated new piston and cylinder, tightened cylinder down. Turned motor by hand with flywheel weight. Everything felt good until the piston was at the bottom of the stroke. Something was in a bind and I could no longer turn it either way. Removed cylinder nuts and took pressure off the base gasket. I was then able to turn it again by hand but could hear metal to metal contact at the bottom of the stroke. Pulled it apart and I can't find any evidence of where the contact is happening. I believe the skirt on the bottom of the cylinder is contacting the crank on that portion of the stroke. Almost like the crank is not perfectly round. Any help or suggestions would be greatly appreciated. I was considering lightly coating everything with some grease to see where the contact is happening.