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Discussion Starter · #1 ·
Hi, I'll try to put my problem here again.

Somewhere around the engine, I heard a scrub. It's a regular intermittent sound. Like scratching, scrubbing. This sound appears each time a lower gear is engaged. When we ride in two people, the sound is not so loud.

The sound is emitted when:

- I downshift without adding throttle

- When I release the gas

- when I overcome a pothole, it makes the same sound for a short time.

When I downshifted from 4 to 3 and quickly released the clutch. There was a very loud sound. . It's like grinding gears in a gearbox. It only happened once. As I watched the clutch, it made sounds as I wrote above.

Thanks for the tip.
 

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Hi,

From your description with it being quieter with a passenger, I would be checking the chain tension. With a passenger on, the rear of the bike will sit lower. This will change the tension on the chain. When the engine in decelerating, the chain tension also changes. If you're not sure how to do it, I think the manual shows how to check and adjust, otherwise there should be instructions on the forum somewhere. If you haven't got a rear stand, it may be easier to take it to a mechanic to be checked.

Good luck.
 

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Discussion Starter · #3 ·
Thanks for the reply.

It's a sound coming from the space between the front wheel and the engine.

Someone here suggested that it could be a timing chain.
If the chain is replaced, how much time can the mechanic spend on this time change?

Thanks again for the reply :)
 

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It may sound like it is coming from the front, due to the way sounds move around and reflect off different surfaces.

If you're not getting the sound when accelerating, I would doubt the timing chain is the issue. Some bikes seem to be worse than others, but the timing chain tends to make the most noise around 6000 rpm.

Checking the tension on the drive chain doesn't cost anything and would be the first thing I'd be looking at if you don't know when it was last checked. There is a sticker on the swingarm that shows what the slack should be on the lower section of the chain. If the chain is too loose or too tight it will cause trouble with the sprockets and possibly the transmission. If it is too loose it can even slip on the sprockets or come off completely and lock the rear wheel up while you are riding.
 

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Discussion Starter · #6 ·
It may sound like it is coming from the front, due to the way sounds move around and reflect off different surfaces.

If you're not getting the sound when accelerating, I would doubt the timing chain is the issue. Some bikes seem to be worse than others, but the timing chain tends to make the most noise around 6000 rpm.

Checking the tension on the drive chain doesn't cost anything and would be the first thing I'd be looking at if you don't know when it was last checked. There is a sticker on the swingarm that shows what the slack should be on the lower section of the chain. If the chain is too loose or too tight it will cause trouble with the sprockets and possibly the transmission. If it is too loose it can even slip on the sprockets or come off completely and lock the rear wheel up while you are riding.
Yes, it doesn't do it when accelerating. So I'll try to check it again, thanks for the tip :)
 
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