Really bad vibrations
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When you say mad vibrations, can you elaborate? Is it when the bike is stood still and just revving up? Or moving?
I’ve had a main/crank bearing cage fail on a 4stroke. It let the ball bearings ‘slap around’ out of balance. It really threw the revving up out of whack...
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Sorry for the late respond.
It is vibrating even when I stands still I neutral. Could it be that’s the bushing are the cause? Or maybe something else? -
If it’s doing it stood still, I’d suspect the main bearings. Especially if it’s erratic to rev up and down? If the cage disintegrated the ball bearings would group together and throw the balance off. It’s what happened to me...
You’ve already had the clutch cover/casing off, did you check all the drive nuts were tight? Crank, clutch, balancer shaft, ect...
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Hmm yea, maybe it could be the bearings, although I changed one of them last winter, I know I should have changed both but I only have one
Yea, all of the nuts were tight and no loose nuts -
@Calum
No, all are tight and good! -
Hmm yea, maybe it could be the bearings, although I changed one of them last winter, I know I should have changed both but I only have one
Yea, all of the nuts were tight and no loose nuts@Haako-Smith
I just re read your first post. It won’t rev up...
One thing you can try is to turn the engine over by hand. Turn the magneto rotor over, back and forwards, see if it feels ‘crunchy’ at all. Anything but smooth...P.S. has the posting format changed? I could only find the ‘button’ I normally use in the first post. I’ve never seen the @whoever reply thing before...
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@Haako-Smith
I just re read your first post. It won’t rev up...
One thing you can try is to turn the engine over by hand. Turn the magneto rotor over, back and forwards, see if it feels ‘crunchy’ at all. Anything but smooth...P.S. has the posting format changed? I could only find the ‘button’ I normally use in the first post. I’ve never seen the @whoever reply thing before...
@SpookDog
Hey.
The I tried to rotate, and it feels like normal. Nothing crunchy or anything. I also tried to swap the clutch basket out with another one I had laying around, which I knew worked when I took It off. I started it up and with no luck, same vibration
Yea I also saw the @thing haven’t seen it before.
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@SpookDog
Hey.
The I tried to rotate, and it feels like normal. Nothing crunchy or anything. I also tried to swap the clutch basket out with another one I had laying around, which I knew worked when I took It off. I started it up and with no luck, same vibrationYea I also saw the @thing haven’t seen it before.
@Haako-Smith
dude, if the engine is tight in the frame and you’ve already been clutch deep. You’re going to have to go deeper. It can only be something that’s spinning and out of whack. Which is clutch side (input) gear shaft, balance shaft and crank. There is nothing else. My concern is that if the bearing race has failed, where is the metal? It could only go out round the inner crank case...
Only other thing I can think of is the rotor woodruff key. Remove the rotor and check the keyway on the shaft. I’ve had these go bad and ruin the key slot/hole, no matter how much I tightened it it wobbled loose. I had to braze a woodruff key into the crank in the end... -
@Haako-Smith
dude, if the engine is tight in the frame and you’ve already been clutch deep. You’re going to have to go deeper. It can only be something that’s spinning and out of whack. Which is clutch side (input) gear shaft, balance shaft and crank. There is nothing else. My concern is that if the bearing race has failed, where is the metal? It could only go out round the inner crank case...
Only other thing I can think of is the rotor woodruff key. Remove the rotor and check the keyway on the shaft. I’ve had these go bad and ruin the key slot/hole, no matter how much I tightened it it wobbled loose. I had to braze a woodruff key into the crank in the end...@SpookDog
Hmm yea, I took the woodruff key out, and it looked good. Maybe I just have to start taking it apart
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@SpookDog
Hmm yea, I took the woodruff key out, and it looked good. Maybe I just have to start taking it apart -
When i was riding today, all of a sudden my bike started vibrating like mad. And it seems like it won’t Rev up. I checked the balancing shaft and flywheel, which all seems fine. However the clutch basket has quite a bit of play between the actual cog and the basket. Could this cause mad vibration? Or what else could?
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You can always pop the oil seals before you split the cases. Whatever, you’re gonna have to take off the top end to get a look at the crank. I think surgery is the only option
This post is deleted! -
@Haako-Smith have a look at the bottom end bearings very easy to mis hap for good wen bad pal just had the same thing 1 of the bottom bearings were shot hope this helps pal
@james
Thanks for the tips!
I have a spare engine that I will swap it with in the meantime.
Thanks to everyone who have helped!
