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Posted (edited)

Hey boys, so a little update with my Yamaha, I now have the CDI box that came in and it’s getting really good spark, but when I go to turn it over, I hear a clanking noise that sounds like something is loose, so I took the stator cover off and my flywheel came off the crank and was magnetized on the stator, nothing serious but like it was unbolted. Is there a way I can keep it from coming off when I turn the motor over? I heard you gotta torque it down with an impact but idk if it’ll work for sure and I’m trying to get this bike back on the road/trails, but at the same time, I’m at the end of my rope with it because it’s getting aggy, but if anyone knows how I can make the flywheel stay on, lmk because some help would be gladly appreciated.

Edited by That229Yamaha
Posted

Well the flywheel should have a key to align it with the shaft, and a nut and washer or possibly two washers.. so you'd better fish them out of where-ever they are. Then you need to hand fit the flywheel onto the shaft without the key or nut and turn the flywheel on the shaft(shaft not turning) checking it fits on nicely with no rocking or wobble to it. If it sits on the taper nicely then take it off and fit the key and flywheel and give it a bit of a wobble to make sure it is still sitting nicely and not being held off-set or not right on because of the key. Then if it's still fitting nicely fit the washers and nut and tighten it and use something close against the flywheel as you trun the flywheel checking it's running concentric and not bent or wobbling. If you mount something right close to the flywheel you will see the gap changing if it's bent. If it all looks right then use a socket and bar and tighten the nut up. Don't use an impact wrench because you won't notice if the threads don't feel right.. Use the bar and tighten it down checking it behaves as threads should.. going up tight and then progressively tighter in the last 1/4 or so of a turn.

Posted

Well if the flywheel came off then the nut and washers are missing, you have to find those, and the key, it may be in pieces, but you need to find the pieces, dont want any pieces floating around in the sump, even though they dont float they could cause problems later. Check to make sure the keyway and crank threads are not damaged and put everything back together by hand as Mech suggested if everything goes back together smoothly torque nut to 100ft pds. I used a ratchet wrench on the flywheel to hold it while i torque the nut, i dont like to use impact wrench for that. 

Posted

That unit should have a pull stater with a rope if I remember correctly.  The Bolt and washer are outside the outer cover and should be tightened to 36 ft Lbs as per pages 4-64 in the manual.  Pages 4-63 have good pics so you can Identify the parts and how to assemble them correctly.  Please use a torque wrench and torque it correctly so you don't have further issues.

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