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grinding transmission in neutral

mchapa

CB750 Enthusiast
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Hi Everyone....

Seems like I have a grinding noise coming from the shifter side of the transmission...
when it is in neutral and the clutch released.... If I squeeze the clutch lever...
the grinding noise goes away....there is also a whining noise in 3rd and 4th gears...
What do you guys think????
 
Sounds like you may have a bearing in the tranny getting loose letting the gears start to mesh. Or you have a bent shift fork. Either way you gotta split the case to get at the tranny parts to inspect. May be worth pulling the shifter cover just to make sure the shift drum and linkage aren't binding.
 
Grinding gears

Sounds like you may have a bearing in the tranny getting loose letting the gears start to mesh. Or you have a bent shift fork. Either way you gotta split the case to get at the tranny parts to inspect. May be worth pulling the shifter cover just to make sure the shift drum and linkage aren't binding.

Could it be the clutch or clutch basket????or maybe an outer bearing???
 
Clutch would be making a bunch of noise on the right side. Only one bearing can be changed without splitting the case...the bearing under the left side cover. Its in the bearing housing held in by 4 philips head bolts. Never seen one bad.
 
Clutch would be making a bunch of noise on the right side. Only one bearing can be changed without splitting the case...the bearing under the left side cover. Its in the bearing housing held in by 4 philips head bolts. Never seen one bad.

Took motor out....going to split the case....
 

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Can't find anything wrong
 

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Some baskets are spot welded, Others are stake peened at four spots, and some have no ring. It should not be loose. It,s probally just Me but the center fork in pic one looks bent but I look at pic five looks OK, Dirtdigger knows more about this stuff that I, Take care.
 
Post a picture of the shift forks on the shaft but a straight on shot..that center fork looks a little funny to me too but it may be the angle of the picture. Band should not move on the basket. Any of the bearings feel rough or loose? Are the small pins on the end of the shift drum loose? How does the primary chain tensioner wheel look?
 
The band moves about 1/8 of an inch in an out...... the bearings do not feel rough..and are smooth and quiet....the pins are not loose.....and the primary chain was tight before I split the case......People in other forums tell me that it's a clutch chatter.... and I will post a pic of the forks ...straight on shot.....
 
I was talking more about the tensioner then the chains. If the roller is getting hard and or starting to chunk then the chain will bounce making a bad noise. If the motor has more then 30,000 miles then the chains really should be changed as they stretch pretty fast. As far as the clutch basket, if the ring moves get a different basket. Lot of parts available on ebay. People often thing the clutch makes noise but in reality it is gear backlash in the trans. When the clutch is pulled in more of the gears are in free spin and less teeth chattering, worn primary chains add to this noise. But beings there is a problem with the clutch basket it very well could be contributing to your noise. You are probably just going to have to make a judgement call as to if you want to replace internal parts or just try the basket. Would be a good time to stick a different gear set and bearings in there so you dont have to split the cases again to chase a noise that may or may not be normal. Kind of hard to diagnose noises over the internet.
 
I have a very similar issue. While in neutral I hear a knocking/clatter. I don't notice any issues while in gear or while shifting.

You mentioned it was the basket--what exactly? Was the gear loose?
 
Cycle x replaced everything inside the clutch basket . I guess it was clutch chatter.....
By the way.... in low rpm...you will hear gear backlash...
some motors are just a little noisier than others...
 
I suppose I'll just leave it alone then. Everything works fine--just a strange (to me at least) noise when I'm in neutral or pull in the clutch lever. The noise goes away when I'm in gear whether it's low or high RPM. This is my first bike so I suppose it's something I've got to get used to. Thanks
 
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