Loud screach upon engine braking.

Hello Moto!

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So I threw a brand new motor on my bike just for the hell of it and something is goin on with it. I get a pretty loud screach internally in the motor when I pull in the clutch to brake. It seems worse at higher speeds.

I think it might be the clutch but I'm not sure what to look for. What would be causing it to screach sounding like metal on metal. I know its not my chain. Seems to run fine just the loud screach lol.

Any ideas?

The bike rolls freely when the clutch is engaged by the way...
 
You will have that on a new engine sometimes, I would remove the right side cover and check the small gear mounting bolt/screw. Add a small amount of grease where the two gears mesh, not too much or it will get on the clutch pads when the engine gets hot.
 
You will have that on a new engine sometimes, I would remove the right side cover and check the small gear mounting bolt/screw. Add a small amount of grease where the two gears mesh, not too much or it will get on the clutch pads when the engine gets hot.

Thanks I'll try that. I just thought it was weird because my other motor didn't have this issue.
 
Let me make a correction here. It makes the noise when I am just letting off the gas and not pulling the clutch. Engine braking I have heard it called before. So when I'm goin along and just let off the gas it makes the noise. When I pull in the clutch it doesn't make the noise. Sorry for the confusion.

I did add a little grease.
 
it could be...the little gear inside he clutch cover popping out and hitting the cover. an idea.

I don't think that's it. I loosened up the flower nut on the pressure plate a tad and ran it with the cover off briefly. The noise was still there but maybe a small bit less dramatic.

I hope it's not a bearing or something.

You will have that on a new engine sometimes

Maybe it will work itself out after a little mileage? I just hope it's not something really damaging. I didn't have this ever happen at all with my other motor. I just decided to mount this one for s**ts and giggles but now I'm not laughing o_O
 
The only way the small gear can hit the cover is because the mounting screw is loose or the crankshaft has way too much side play. What you described is a result is a result of gear teeth chatter, since we can't adjust the depth and back lash we are kinda stuck with what we have. If you run it with the side cover off watch both gears for excessive wobble or run out, you can replace either if so. One of my engines from eBay was pretty bad , after a few hundred miles its hardly noticeable.
 
Funny thing. My brand new GT5A makes the same noise as that gasbike motor! I guess I can live with it but damn it's annoying. I'll double check some things tomorrow but if it's gonna make that noise...Oh well I guess. Not exactly impressed.
 
The more you ride it the more it comes out.... I wouldn't worry about it, but also in the type if it blows the crank out the jug I'm the first taking pictures lol
 
the primary gear and th clutch gear do make a lot of noise. I hastened their mating process by removing all grease and putting valve grinding paste on and left it on till the noise was much reduced. I looked and the gear edges were then rounded off. I then spray cleaned them off and applied grease.
 
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