125-200cc CR125/144 Lower End

Hey Guys,

Curious as to what everyone has been experiencing for the longevity of the lower ends?

Thanks!

2014 CR125. My left crank seal went at around 120 hours, leading to top-end seizure. I did basic check of bottom end (rod side clearance, check for any play, etc) and found no reason to do any lower-end service beyond seal replacement.

2008 wr144
My top end got hungry so it started to eat my gear oil (yummy)
Probably due to a bad right crank seal, im hoping that will fix my smoke and oil level issues because replacing that seal doesnt involve splitting the case.
I started to hear a light growl recently, im not sure if its a crank bearing or one of the connecting rod bearings. Its a high pitch growl so i think its the top end, and when i upgraded to the 144 kit i didnt replace the top end bearing If its the crank bearing that will be the next issue.

325 hours on my 150/165 before the big end rod bearing starting making noise. Cooked a few trans side crank seals doing hard enduro crap but no problems beyond that.

Had two big end replacements, two 2nd & 4th gear cogs replaced, three clutch basket replacements in 20 years, but wet side oil seal replacement every 2nd piston between 16-24 hrs depending on track conditions clutch friction plates as needed i ve had one collapsed bearing on the power valve actuator but it was brand new and faulty so I sent it back and SKF replaced all the transmission bearings foc just cost me another gaskets set no other issues to report as long as you change the transmission oil and pistons/small end bearings regular you will be all set