I've posted several times over the past few months about a "whining" or "chirping" type of sound I've been hearing. While moving, if I let off of the throttle I can hear the aforementioned noise. While acclerating or maintaining speed, there is no noise. It seems to only happen when the bike is being slowed by the engine a bit. I changed the oil last weekend and switched to Mobil 1 75W-90 Gear oil and the sound is still there.

At first I thought I may have had a tight primary chain, but over the past couple of days I believe the noise is coming from the drive belt side.

So I was wondering what might cause something like this. I don't know of anything that has to be lubed or maintained on that side of the drivetrain. I don't think the drive belt is out of adjustment, and I'm sure it's not too tight.

Any thoughts? We're going to have some rainy weather over the next couple of days and I'd like to correct this problem.

 

Did you check the motor mounts?

 

No I didn't but I believe the noise is in the drivetrain somewhere. While I have the bike on the lift I'm going to check a number of things and I'll include the motor mounts as well.

 

Try pushing the bike, not running, a few feet. If it's your belt chirpin you'll know right away. Mines done it for years.

 

As the belt gets old it may make noise. Jack up the bike a bit and wash the belt. It's a pain but can make some noise go away. One belt I had was very noisy for ~5k miles no matter how I cleaned or adjusted the tension.

 

The bike now has about 15k miles on it and I was actually considering that the belt could be the source of the noise. How would I wash the belt? I noticed that the toothed (inside) of the belt appears a bit shiny - as though some metal has become embedded in it.

BTW, I took a 40 mile ride after work and the noise was virtually non-existant by the time I got home.

 

Get a belt tension tool if you dont already have one, they're cheap. They come with instructions and of course the book has info. Too loose or too tight will make noise. HD makes a "Belt Dressing" for drive belts that is just silicone spray. I get good results with LPS1, which goes on wet and then drys so as not to accumulate dirt. As to washing, warm soapy water and a brush a little bigger than a toothbrush. The bottom (moving towards the rear pulley) has a guard, but the top side bottom is open under that guard and you can wash there. Any silicone from a car parts store is the same as HD belt dressing.

 

Even changes in humidity seems to cause a squeak some days. Old biker described cleaning. I use a floor jack to lift the rear enuf to spin the wheel and clean a few inches of belt at a time. It is a pain but cleans the belt.

Shiny is not a problem, nor are minor grooves from the uneven wear patters of the chrome rear sprocket. The front sprocket is hardened steel & not likely to be worn out untill over 50k miles.

 

I first noticed this noise when it was a humid night and the roads were wet from a shower. It seemed like once I rode over some wet roads, I could hear the noise more. I got caught in the rain on the way home and it was pretty loud as well. So I agree - I think the conditions do affect the amount of noise generated.

I'll try to clean the belt this weekend and see how things work out. What type of silicon cleaner should I look for?

 

Mine squeaks and whines and chirps sometimes. I can find no consistency with it in regards to weather and I have been riding it 11k so I am assuming that it's normal.