Can I file ridges smooth on primary clutch fingers ?

You know them ridges that form over time from clutch friction discs rubbing on the primary clutch fingers. my question is can I file those ridges smooth again to try and prolong the life of those fingers because that part is no longer avaliable from yamaha for a 1980 yz 465.


Yes you can. Just be sure to try and keep everything as flat and straight as possible, and round off the edges at the inside corner of the fingers. Filing a sharp 90 there can lead to cracking.


I hate to differ with the post above but let me share my experience with you. I had a 95 RM-250 with worn clutch fingers and a friend with a machine shop. I took the clutch basket to him and he put it on a computer operated grinder that took an even amount of off each clutch finger until they were all smooth. This did 2 things first, it allowed even engagement of the clutch (all of the clutch tabs made even contact with the fingers and even pressure) which was a good thing. Secondly it also allowed play or slop between the clutch fingers and clutch tabs which was a bad thing. I found out number 2 was bad when I started finding pieces of clutch disc in my oil. On further inspection several clutch plates shattered due to the slop between the clutch fingers and clutch tabs. On deceleration the clutch tabs would move to the rear finger and on hard throttle slam into the front finger, they are not designed for that kind of stress. I would recommend looking for a used replacement or finding a new one in some small shop that has old parts lying around.


I've done this many times and a few different bikes. I've never had a problem. will create more slop like previously stated and the extra slop will create new divots quicker then the previous divots were created. If you are really hard on your clutch, then you won't get alot of life out of this basket. On the other hand if you are light on the clutch then you might be good for a few years.

When I do it, I gently clamp it in a vice and I use two different files. A course one to get rid of most of the divots, and a finer one for cleaning up the edge really nice. Don't forget to unsharpen the edges afterwards too. Try to file down each finger about the same so that all engage at the same time.

You can also get the basket hard anodized after your done. That will definitely add some life to it. I've never done it myself, but I've heard of guys doing it with good success.


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As stated above filing the basket is at best a very temporary solution until a new basket can be found. In your case that appears it's going to be a problem.


Old MX Racer
When you file the fingers watch the old grooves,if you file all of them till the high spots are gone the better.Caution,the file removes a lot of metal, ten thousandths here or there add up and can be detrimental to your plates! Do you know someone to fabricate stainless covers to go over the fingers,share wisecos idea!And of course you will be putting in new plates.


On the auction site right now theres a whole new clutch including, basket, primary drive, pressure plate, inner hub, old plates, new plates, and new springs for $160 canadian.