1990 Yamaha Yz125 clutch issue

Adam104
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Adam104
I recently purchased and restored a 1990 Yamaha YZ125. Everything has been gone through, fixed, repaired, and restored to factory or near factory condition expect the clutch. I have tried everything but the clutch will not fully engage. The clutch has been completely redone with aftermarket springs, plates, and metals. I also purchased a brand new lever (adjusted to the correct play) and a 1992 Aluminum clutch cover (due to the fact the 1990 clutch cover had a tendency to flex causing these issues). Everything is adjusted to proper specifications, the clutch internals are positioned correctly (they have been taken out and gone through 10 times) and the clutch finger down by the clutch basket is positioned correctly between the two lines. Is there anything else it could possibly be, or something I am missing? Is it the aftermarket springs? This bike has less than 10 total hours and in near perfect condition, I don't want to let something so small ruin this timeless classic. Any suggestions will help!
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Dekon
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Dekon 3/19/2019 5:28pm
3/19/2019 5:28pm
Hey Adam, for some reason I could not respond to your PM. My YZ125 is a 1989. All I did with mine was to go to the aluminum clutch cover. I did have some serious drag with the original cover. Put the newer cover, problem solved. I have heard of issues with aftermarket clutch parts being to thick, not sure if you used those. One thing with the 89 and 90 is that fork springs are nonexistent. I want to ride mine so I put a 91 front end on it; bolts right up(thought you have the 90 with the cool red anodized upper tubes).
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Adam104
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Adam104 3/20/2019 6:10am
3/20/2019 6:10am
Dekon wrote:
Hey Adam, for some reason I could not respond to your PM. My YZ125 is a 1989. All I did with mine was to go to...
Hey Adam, for some reason I could not respond to your PM. My YZ125 is a 1989. All I did with mine was to go to the aluminum clutch cover. I did have some serious drag with the original cover. Put the newer cover, problem solved. I have heard of issues with aftermarket clutch parts being to thick, not sure if you used those. One thing with the 89 and 90 is that fork springs are nonexistent. I want to ride mine so I put a 91 front end on it; bolts right up(thought you have the 90 with the cool red anodized upper tubes).
Thanks for the response. I will have to go buy an OEM clutch rebuild kit if they even still make them. I should have started with the aluminum clutch cover and worked my way from there. I have also heard on not great things on the 88-90 Forks, and yes mine did come with the very cool and unique red forks. I do plan on riding it every now and again so I will definitely be getting them redone. Appreciate the help, this clutch has been throwing me for loops. I have taken the entire thing apart 10 times and just cannot get it to work right. I've been working on bikes my entire life and haven't ever come across anything this stubborn.
Dekon
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Dekon 3/21/2019 8:35am
3/21/2019 8:35am Edited Date/Time 3/21/2019 8:37am
I have no idea if this matters or not, but did the clutch kit you bought have the two different friction plates for the ends of the clutch pack? Did you put the clutch boss spring in? Just throwing ideas out there.

#13(2 of them) & 14 in the below diagram link.
https://www.ronayers.com/oemparts/a/yam/50042eebf8700209bc78a594/clutch
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Dekon
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Dekon 4/22/2019 8:51am
4/22/2019 8:51am
Any update?
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Adam104
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Adam104 5/2/2019 9:23am
5/2/2019 9:23am
Dekon wrote:
Any update?
Sorry for the late response. I just ordered the new OEM clutch springs this week from the site you sent me, been busy working on my race bike. I have taken apart the clutch once again, checked each plate and fiber, ensuring they were all in the correct order and reinstalled the 1991 aluminum clutch cover. The clutch kit is not OEM but is a direct replacement for the 1989 Y125. I am thinking that the clutch springs are either the wrong size, too stiff or a combo of both which isn't allowing the clutch to engage properly. Hopefully, the OEM springs will help. Unfourtanly, that is the last possible thing I can think of doing. If it doesn't fix the issue I am probably going to put it up for sale, I really don't have room to store a bike that I cant race. Thanks for your help!

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