Question about 2003 Yamaha YZ 125

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Puting wrong oil in transmition

Ive been told that if i have got 10w30 oil in my transmition instead of 10w40 it will cause my clutch plates to expand is this possible?
because my yz 125 2001 model stays in grear even with the clutch pulled in, i know when i pull the lever it is lifting the presure plate as i can feel it. ive opened up the clutch and took all the plates out and everything seems to be fine the inner hub moves freely without touching the outer  clutch basket, the prombel only happens when i put it all back together, which makes me think mibby the frictionplates ect have maybe grew . any sugestions will be very helpful thank you. Ryan Dundas.

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The problem did not start untill the 10w30 Honda transmission oil went in. It isn't the 10w30 thats the problem. It's the TRANSMISSION oil as opposed to MOTOR oil. There is a difference. As I said before, the swelling may or may not go away.

Best wishes Ryan :)

Posted on Apr 19, 2009

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Did you use oil rated for a motorcycle with a wet clutch? If not and you used regular motor oil you have in fact trashed your clutch plates.

Posted on Apr 19, 2009

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How do i fix my handle for the clutch cause it got very loose and it doesnt even go back up once i squeeze it, i cant even change it to gears and i tried tighten the little knob where you can loosen it or...

If you put synthetic oil in the gearbox that is the problem. Synthetics can swell the cork on the clutch friction plates causing the problem you describe. New friction plates and a change back to standard 10w40 motor oil is what will be needed.

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Putting wrong transmition oil in yz 125

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Apr 19, 2009 | 2003 Yamaha YZ 125

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Apr 19, 2009 | 2003 Yamaha YZ 125

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Yz 125 2001 stays in gear when clutch pulled in

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Apr 17, 2009 | 2003 Yamaha YZ 125

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Bike stays in gear with clutch in

You are saying that with the clutch lever pulled in the bike still wants to go forward. Generally that is caused by dirty, gritty oil in the gearbox. Go ahead and change the oil. 10w40 motor oil is what you want. I think that will fix the problem assuming the clutch plates were installed properly. The first plate installed and the last plate installed should be a fiber friction plate, 8 plates total. A metal pressure plate goes between each fiber plate, 7 plates total.

Be sure the lever assembly arm is installed so that it gets full movement of the clutch cable. If the full range of movement is not present then full disengagement of the clutch is not going to happen.

cape cod bob did you a good service in the manual referral. Be sure to say thanks.

Apr 16, 2009 | 2003 Yamaha YZ 125

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