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My first transmission rebuild.. with pictures! 2000 Yz125

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Whats up guys first off let me start off on why I'm doing this.  A few months ago I purchased a used 2000 yz125.  The guy i bought it from replaced the piston and all the gaskets but that's all the work he said he did to it.   It needed some more work so I figured I'd buy it. Not only to learn, but have fun doing it. So far I did a clutch and a carb rebuild.  When I took it for a test drive I noticed it was skipping, but only in 2nd gear. When I mean skipping, I mean it literally seemed like there were some damaged teeth on 2nd gear. It was hard to tell over the sound of the engine, but it seemed like there was a little bit of grinding also, but only in 2nd gear.  Despite the 2nd gear problem, shifting through all the gears were fine. So I knew it was time to split the cases open.  When I finally started inspecting the gears it was clear there were metal shavings, but all the gears seem fine and I don't see any damage to them. Taking the shift forks out, the "L" one was pretty chewed up. The "R" one had some markings on it but wasn't as bad as the "L" one.  All the bearings on the case seemed to be a little rough also. Could the chewed up shift fork be causing only 2nd gear to be acting up?  What could of caused this to happen in the first place?  Any answers would be awesome! Here are some pictures I took.  IMG_20140425_194008532.jpgIMG_20140425_194511000.jpgIMG_20140425_195710117.jpgIMG_20140425_200359228.jpgIMG_20140425_202321123.jpgIMG_20140425_202607163.jpgIMG_20140425_201437569.jpg

Edited by monstergt88

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i forgot to mention that the counter shaft was rubbing on the bearing as well.  I will be posting a picture tomorrow so you guys can see 

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i forgot to mention that the counter shaft was rubbing on the bearing as well.  I will be posting a picture tomorrow so you guys can see 

how are you uploading here? i still cant figure it out...

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Yes, the damaged shift fork might be causing the shifting issue. It might be bent slightly, almost imperceptibly, which is not shifting the gear over far enough to actually engage 2nd gear fully. Look everything over very carefully, and point out anything that doesn't look perfect. We're here to help!

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Here's the other picture of the piece that is gouged up due to it rubbing. That actually makes a lot of sense with 2nd gear not fully engaging. What do you think this gouging is from?

1398639436854.jpg

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Ok makes sense. Do I just take the bearing retainers off and the bearings come out or do I need a special tool to get them out?

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Looks like a thrust washer is missing where it ate the retainers..have you looked at parta diagram to make sure everyrhing is there and where it needs to be

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