Engine noise.

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10 inch Terror
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Hi all, when my motor is running its giving off a metallic sounding noise that goes away when I pull the clutch in. Any ideas as the the problem and how to solve it? Thanks in advance Pete.
phil23fair
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Is the noise there with it in gear or out of gear when you pull the clutch in?
10 inch Terror
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It's there when it's out of gear. I haven't got the gear cables connected yet.
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HxPaul
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It could be the teeth of the kickstart catching on the first gear,it could be a noisy gearbox or it could be the kickstart catching on the clutch top plate.All these sounds will go away to some degree when the clutch lever is pulled in because it stops the gearbox revolving,although the last one usually makes a scraping sound.
10 inch Terror
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I've had the side casing off and there is no sign of the top plate rubbing and the kickstart teeth are not sticking proud when in the kickstart ramp. I've put an extra thick gasket on to give more clearance and the noise is still there until I engage the clutch. Anyone have any ideas?
Grumpy225
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If the noise goes away when you pull the clutch you need to check the gear box. Usually that means the end plate bearing is on its way out, shimmed wrong or the end plate is loose.
10 inch Terror
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Grumpy225 wrote:If the noise goes away when you pull the clutch you need to check the gear box. Usually that means the end plate bearing is on its way out, shimmed wrong or the end plate is loose.
Brand new bearing and the end plate was torqued to the correct setting. Supposing it was shimmed incorrectly how would that cause the noise? I'm not doubting you I'm just trying to get my head around it. Cheers Pete.
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HxPaul
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My gearbox makes a noise until I pull the clutch lever in and stop it moving.
Grumpy225
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10 inch Terror wrote:
Grumpy225 wrote:If the noise goes away when you pull the clutch you need to check the gear box. Usually that means the end plate bearing is on its way out, shimmed wrong or the end plate is loose.
Brand new bearing and the end plate was torqued to the correct setting. Supposing it was shimmed incorrectly how would that cause the noise? I'm not doubting you I'm just trying to get my head around it. Cheers Pete.

If it's shimmed wrong then the gears will have a lot of float to them and rattle. Also if the tree gear is not torqued to speck it can cause excessive movement when the clutch is not engaged. Once you grab the clutch the noise goes away because there is force being applied to keep things from floating around (if that makes sense).

Many years ago I forgot to fill my motor with gear box oil and then went on a 100 mile mountain ride. By the end of the day my motor was making the exact sound you are describing and would go away when I grabbed the clutch. When I split the case the endplate bearing and main shim were toast and allowed for excessive movement in the gear stack and tree.
10 inch Terror
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I may of been a bit silly here. I didn't fill the case with oil because I wasn't sure if everything was ok and didn't want to have to drain it all again to restrip if there was a problem. As said the bearing is new and the end plate and clutch nut are both torqued correctly. I also made sure the gearbox is shimmed within spec going by Sticky's book. Would filling the case with oil lessen the noise and have I been a complete numpty here?
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