nasty looking piston 2003 rm 85

[whenfoxforks-ruled]

Even the VERY nice motion pro separator, you need the correct size case bolts. Get as many bolts into the cases, and use the center draw bolt to push off the crank. Hit the counter shaft once in a while with a dead blow to keep the separation even. Honestly, a 1/4th inch plate of aluminum, attach 2 draw bolts off a c clamp, and match all the case holes, would work even better!

 

[rmrider45]

today i took apart the top end that i had put in and it looks worse than than the one i showed here in the pics. so i took the motor out of the frame and looked down at the big needle bearing on the bottom of the rod and it looks ok. i am thinking one of the big bearings on the crank are coming apart. when i get a chance in the morning i will try to get the ignition rotor off with a puller . then the fun part will be to try to seperate the case.?i only have to pull apart the left side of the case with the ignition rotor to do this job? :ride: :ride: :ride:

if it isnt the needle bearing coming apart it has to be one of the big bearings? thx

 

[whenfoxforks-ruled]

First, check the thrust washer clearance with a feeler gauge. Second, get a light and magnifier to look at all the needles in the bearing. Thrust washer clearance, cracking in the needle bearing cage, damaged needles, sometimes it gets hot and turns the big end of the rod blue, and look for dis-coloration on the journal. If it was the main bearings, there should be up and down play at the rotor or the drive gear(the ends). If that is the case, the crank is probably okay, except for the 50 or so race hour lifetime?

 

[rmrider45]

i looked in with a light and all the needle bearings look good threw that slit in the bottom of the rod. the rod does have some play in it when i move it back and fourth tho