Author Topic: YZ125G clutch - help please  (Read 1155 times)

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Offline Digga

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YZ125G clutch - help please
« on: January 21, 2014, 04:05:57 pm »
Can anyone out there please help me out with the following issue I am having with my 1980 Yamaha YZ125G clutch.

Bought the bike about a year ago & although it looked a bit run down & neglected, it was mostly all there so I bought it. When I picked it up, I took it for a quick ride & seemed to go OK, went through all the gears etc. & felt good.

I have since stripped the bike & rebuilt it only to discover that the clutch now does not disengage the drive.

I have got a new clutch cable on it, the plates are fairly new & all measure up within spec, tried new clucth springs, had Valvoline Premium XLD 20W50 oil & then ATF. Combinations all of which seem to make little or no difference, just won't budge.

The outer clutch pressure plate moves in & out away from the friction plates about 10 mm when you pull the clutch lever but the friction plates/metal clutch plates stay together in the clutch boss assembly. I dont know if this is normal or they are suppose to all move out with the outer pressure plate???

For someone who has little or no knowledge of the workings of 2T bikes, this is my first experience with a clucth & I have now had the thing in & out more than a dozen times with no success. I havent even started the bike yet, just spinning the real wheel to see if the clutch will work, so very frustrating.

Feel free to comment & dont worry if the answer is something simple, I wont be offended because I dont really know what I am doing, cheers  :'(  :-\ :-[ :o

1977 Yamaha YZ250D, 1977 Yamaha YZ400D, 1980 Yamaha YZ125G

Offline smed

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Re: YZ125G clutch - help please
« Reply #1 on: January 21, 2014, 05:02:47 pm »
First remove the pressure plate & then remove the clutch plates,try to turn the inner hub,it should spin fairly free(in neutral of course ;)) if not there's your problem,spacer/washer etc in the wrong place or missing,if thats ok maybe a notched basket?   Don't worry too much about not being able to make it disengage with a dead motor,plenty of bikes clutches wont let go that way,start her up & then test the clutch,you will find that a better indication than trying to spin the wheel with a dead motor,centrifugal force will help seperate the plates ;),try it on a stand first just in case there is another problem so it does not take off on you,be carefull of the spinning wheel & chain etc ;)

Offline Digga

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Re: YZ125G clutch - help please
« Reply #2 on: January 21, 2014, 05:08:50 pm »
Thx Smed
The inner hub does spin freely in nuetral so all good there. The basket had a bit of corrosion & stuff on it which I cleaned of along with burrs, scoring etc. It is not NOS 100% but think it is still OK.

I will try getting it started & then see how the clutch goes as you suggest, fingers crossed she will be fine, cheers
1977 Yamaha YZ250D, 1977 Yamaha YZ400D, 1980 Yamaha YZ125G