08... third set of fork seals in 6 months. Thoughts?

I’ve rebuilt the fork seals on my brother in laws rmz three times since summer 2017. The left seal continues to blow after a couple rides. I’m kinda stumped. I’ve rebuilt a lot of forks over the years. He’s a beginner/back pack C rider. Doesn’t do any big jumps and mostly rides harescramble style trails. He’s about 225 with gear. The bike has stock springs. Oil level is set towards the upper end of the capacity. The bike isn’t bottoming by looking at the zip ty on the fork to see how much travel he’s using.


I’ve checked and triple checked the fork lowers. They are smooth and don’t have any nicks or scratches.


I use a seal bullet with electrical tape at the bottom when installing the seals and plenty of grease. Anything is possible but I really doubt the seal is getting torn on the way down.


I can’t think of anything else that would make it blow so quickly. It’s got stock wheelset with stock spacers. I put a straight edge on the lower thinking it may be bent slightly. According to the level and straight edge it’s not bent. I loosened the triples and pinch bolts to make sure it wasn’t binding.



Thoughts? Thanks guys!

New bushings?


What seal are you using - OEM or other?  I had a similar issue on my son's '13.  Was suggested to me by a mechanic that I only use OEM, NOK or SKF.  Ordered a set of OEM and have not had a problem since.

225 is well over what stock springs are designed for, that's probably your answer right there. Even if you "think" he hasn't bottomed out, I would argue that he did at some point and the reasoning for the seal breaking. 

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