Belt drive scare..

Bill Seward · Sep 20, 2017

I was riding the Roadstar this afternoon, when the area around the rear pulley made this really loud noise like a gunshot, and the whole ass end of the bike shook.. I made it home with no problem, and took a look at the belt. Between 2 of the teeth on the belt was a bit of what looked like crushed stone residue. No holes or visible damage to the belt or pulleys. I think the belt may have picked up a pebble. We've got a weekend ride coming up in a couple days, hopefully nothing got really hurt back there. I cleaned up the belt, and gave it a good shot of Armor All to stop the squeaking. Has anyone had this experience with a belt drive bike?

one2dmax · Sep 20, 2017

I had some weird shit like that many years ago on my mom's 650 Maxim. Doing triple digits as always like I did back then and had a hard headshake and bike jumped around for a moment or two then back to normal. Didn't notice anything wrong at the time but a few days later Dad jumped my ass and asked what the hell I was doing. He noticed the fender had dents outward where whatever had been picked up by the tire and passed all the way through it and poked dimples into it. Just got lucky that the tire didn't lock up in the fender. I'm guessing that the speed was both the enemy and friend on that once since it picked up the rock or object in the first place but passed them through there.

1FK00 · Sep 20, 2017

I had an '83 750 Interceptor that would pick up stones bounce them around under the front fender and spit them out the front. No other bike I ever had did that. Just guessing but I figured that they probably bounced off the chin fairing and hit the front tire at just the right angle to bounce back and forth in that confined space as the tire rotated.

Bill Seward · Sep 20, 2017

There is a lot of space between the fenders and tires on a Roadstar. I have heard stones and gravel rattle around in the front fender many times. This was a big BANG, and a very noticeable shock in the drivetrain. Fortunately, it seems to have done no damage. The bike shifts fine, and the drive is smooth and quiet. I'd think if there was a transmission problem, I'd have been calling AAA for a tow..

PATMAX · Sep 23, 2017

Armour All ?! Belt dressing maybe but not Armour All !

RaWarrior · Sep 25, 2017

PATMAX said:
Armour All ?! Belt dressing maybe but not Armour All !

It's a cogged belt, so doesn't really rely on friction like a serpentine or v-belt you'd use the sticky dressing spray on. I've heard of armor-all as a cure for squeaky belts, but generally if they squeak, either the tension or tracking is not set properly and the lubricant (armor all) just temporairly masks the problem. The squeak is usually the belt rubbing against the edge of the pulley since the alignment is off. Also, too much belt tension tends to cause squeaks. Yamaha's seem a little more prone to it than other bikes though. I've never had the issue on Harleys or my Scout- although early build Indian 111's had a recall over noisy squealing belts.

If there's no nicks/gouges in the pulley teeth or damage to the belt, I'd just keep running it. I've seen belts that picked up stones that poked a hole in the belt or put a jagged edge in a tooth that quickly chewed up the belt afterward,