What's that sound?!

[jamezgreen]

Just started hearing a sound more and more that's got me worried. Hoping you guys can help my figure it out. I'll do my best to describe it, it's kinda like a mild scraping or scratching. I only hear it when I engine brake or downshift hard with the clutch engaged. Just hear it for a few seconds then it's gone. It does seem to be happening more and for longer periods of time now.

I have 2 possible suspects: 1. noticed a crack on my front fender, maybe the plastic scraping on itself is making that noise when the weight transfers more to the front tire? or 2. (which seems more probable) noticed my chain seems especially looooose. Could it be clanging around when I downshift? How tight should it be, how can i tell? Is it hard to tighten?

[alantf]

Are you using the front brake at the same time, because scraping suggests (& not knowing the full facts :) ) to me that it MAY be that the brake pads need replacing. Just a suggestion, but it can't hurt to check. :2tup:

If you're at all unsure about the chain, download the manual & check what the slack should be. Offhand I can't remember what the slack should be, but it's not that hard to adjust if you're at all handy with a spanner. Just remember, ADJUST BOTH SIDES EQUALLY to keep the wheel running true. If you're worried about the chain, check it before you ride again. The chain coming adrift while you're riding is just too horrible to contemplate!

[Easy Rider]

If you're at all unsure about the chain, download the manual & check what the slack should be.

:plus1:

And while your at it, check the position marks by the back axle and look for other signs of chain wear.....like it's dry and rusty. You may be due for a new chain (and sprockets). :cry:

You probably should eliminate the chain and cracked fender as possible causes for your noise before you look elsewhere (brakes).

[bonehead]

I noticed a sound for a long time and it really had me baffled. It finally turned out to be the slot cover on the gas cap. It vibrated and made a weird sound. Just happened to put my finger on it while it was vibrating and found the noise. It would do it at high rpms.

[Water Warrior 2]

Just started hearing a sound more and more that's got me worried. Hoping you guys can help my figure it out. I'll do my best to describe it, it's kinda like a mild scraping or scratching. I only hear it when I engine brake or downshift hard with the clutch engaged. Just hear it for a few seconds then it's gone. It does seem to be happening more and for longer periods of time now.

I have 2 possible suspects: 1. noticed a crack on my front fender, maybe the plastic scraping on itself is making that noise when the weight transfers more to the front tire? or 2. (which seems more probable) noticed my chain seems especially looooose. Could it be clanging around when I downshift? How tight should it be, how can i tell? Is it hard to tighten?

Please explain downshift hard with the clutch engaged. Are you shifting down without pulling in the clutch lever ?

[jamezgreen]

It's not a brake issue as far as I can tell since it happens even when I don't use either brake at all. For clarification the noise occurs when I downshift with the clutch lever pulled in, then release the lever at a normal pace to engage the engine and slow the bike down. (just normal downshifting to slow down). After riding more today, I'm pretty sure if it's not the chain its in that area since that's where the sound seems to coming from.

[burkbuilds]

If you have the owners manual, the chain adjustment instructions are on 7-20 and it has pictures to help explain how to check the chain tension. You should not have more than .6" (about 5/8") of slack in the chain according to the specs and that's pretty tight compared to a lot of bikes. If the chain is really loose do not ride it again until you adjust the slack back to specs! It won't take long, and you need to inspect the chain while you are at it, for any visible problems, rust, a link that is frozen, stuff like that. Even if this turns out not to be the source of your noise, you need to do this for safety!

If you don't have the owners manual, download the Service Manual from this site and I think you will find the chain maintenance under 2-70

[jamezgreen]

Update:

Turns out my chain was way toooo loose. Tightened it up per the manual and the sound is completely gone. Thanks for everyone's help.

[bonehead]

Yeah!!!! We fixed one.(well he did)

[burkbuilds]

Way to go Jamezgreen! Don't be to surprised to find that you have to do that fairly regularly to keep it in specs, I had to adjust my GZ's chain about every other time I lubed it. So roughly every 1000 to 1200 miles.

[hotrod5019]

Yes, I figured it was the chain because When you said it was when you downshifted, and it made a popping sound.. I had to tighten up my chain also!