hi all ,took me fly wheel cover off me rev 3 to see if there was up and down movement off the fly wheel as there is exessive vibration and thought maybe mains had gone ,but i have a lot of in out movement is this normal and could it have something to do with the odd knock i thought was detonation-thanks

Sounds like to much end float Remove the clutch side case check the primery gear on crank is not loose or bearing on that side that has failed

ive took clutch cover off abd the bolt on the primary gear is tight

How much movement have you got in MM?

Is the crank moving or just the flywheel?

Check that the flywheel nut hasnt come loose

Check that the washer behind the nut is fitted. Without this there maybe insufficent thread on the crank to wind the nut on far enough

hi,by visual it looks 2/3mm max its on its side as ive took clutch casing off,the crank is moving as well,thanks it gives a clunk when moving it fast

Edited March 15, 201214 yr by skippy1234

That's not unusual, you would need to check it at full operating temp to see if thermal expansion changes it

To diagnose end play knock or "thrust" we used to push the crank end at the nut with a hammer handle with the engine running and see if the sound changed

Do you mean the play is 2/3 rds mm (0.66mm) or 2 to 3 mm. A Rev3s main bearings may be geting tired by this time. I would not run the engine until the mains have been properly checked, it could ruin the crank, the big end the lot (very expensive). The vibration can vary. As the bearing cage wears or or starts to come apart the balls move, causing slackness at times and overtignness at others.

Cheers

hi its 2-3 mm normal mms as on a tape measure ,cheers

That can't be right....0.2mm maybe ...If it was vibrating bad before you stopped it I would suspect not only knackered bearings .big end but crank balance as well.

That can't be right....0.2mm maybe ...If it was vibrating bad before you stopped it I would suspect not only knackered bearings .big end but crank balance as well.

yet

i would say your mains are awol

if i tilt the bike over to the left it rumbles but no noise when leant to the right

The flywheel just shouldnt have any movement at all. If someones not fussy theyll put up with a bit of movement , but i wouldnt.It would be nagging me to sort it.

If your crank pulls through the mains bearings by 2mm, then something is badly worn.

The rumbling when you lean the bike is because one mains bearings is more knackered than the other.

It needs rebuilding mate, new mains and seals may sort you out if you cross your fingers and toes - ha ha

Your local bike dealer will be able to rebuild this fairly cheaply, or you may wish to have a go yourself

Good luck

was the mains ,fitted new ones ,now no play at all ,slight top end rattle now tho-but a great tight engine ,had trouble with clutch but got a syringe from cake shop and back bled in 1 minuete