Rocks and Sprockets

[Roadster Renovations]

I have been doing some thinking about rocks getting into the drive belt sprockets and I am wondering just how that happens. Obviously, the rock is not just sitting on the road waiting to jump up and get into the sprocket. I mean I doubt that the air displacement of the bike would be strong enough to cause a rock to get sucked up in the vacuum. So that leaves the tires kicking them up then. If the rear tire hits a rock, it would have to trap it momentarily as it rotated, then pop out at the right moment at the right angle. That doesn't make much sense to me. So that leaves the front tires. The rocks are kicked up and while they are slightly airborne the bike moves towards them and they are projected into the belt and the sprocket. Does that track to everyone else or am I off base on this? Please weigh in!

 

[PW2013STL]

I agree that I also think it is from the front tires, but the rocks could also be bouncing. Get a handful of small bouncing rocks and one is bound to bounce in.

 

[MisterP]

If the rear tire hits a rock with a certain shape, it will push it out to the side rather than running over it. These, as well as smaller rocks that can get caught momentarily in the rear tire tread, are the ones that can cause problems.

 

[Dragonrider]

Having had more experience with this than I like - especially on new chip sealed roads out here - the Spyder creates a "fog" of particles under it. Small rocks and chips are tossed up by the tires, and ping along on the underside, sucked onto and carried into the pulley by the cogs on the belt. The belt acts like a conveyor - does a really good job of it too.

On sandy roads, while san IS sucked in, it doesn't cause a problem. On chip sealed roads, generally you just hear a constant crunching, with the occasional rock that causes the driver to pucker. On heavily graveled roads, the larger rocks don't cause issues, especially if you have Ron's guard installed (a must have out here) - However, the smaller rocks act in a similar fashion as chips, and end up in your pulley. The faster you ride on gravel, the larger the rocks presented to your high speed pulley. Eventually, you may get one large enough to jamb in the pulley and/or puncture your belt (voice of experience here), and will cost you at least $300 to fix.

For gravel you have three options: (1) avoid it; (2) install Ron's belt guard and go slowly, or (3) ride at speed, and take you chances.

 

[Roadster Renovations]

Having had more experience with this than I like - especially on new chip sealed roads out here - the Spyder creates a "fog" of particles under it. Small rocks and chips are tossed up by the tires, and ping along on the underside, sucked onto and carried into the pulley by the cogs on the belt. The belt acts like a conveyor - does a really good job of it too.

On sandy roads, while san IS sucked in, it doesn't cause a problem. On chip sealed roads, generally you just hear a constant crunching, with the occasional rock that causes the driver to pucker. On heavily graveled roads, the larger rocks don't cause issues, especially if you have Ron's guard installed (a must have out here) - However, the smaller rocks act in a similar fashion as chips, and end up in your pulley. The faster you ride on gravel, the larger the rocks presented to your high speed pulley. Eventually, you may get one large enough to jamb in the pulley and/or puncture your belt (voice of experience here), and will cost you at least $300 to fix.

For gravel you have three options: (1) avoid it; (2) install Ron's belt guard and go slowly, or (3) ride at speed, and take you chances.

Glad you said that, Dragonrider! I think I may have a solution to the small rocks from the front tires. Things are in the works!!

 

[Ben Burped]

Doc, I'm glad to hear that you are on this problem. Please keep us posted.

 

[Bam Bam and Pebbles]

I think Doc started this thread because he does have a solution to this problem. Smart man.

 

[Dragonrider]

Well Doc - don't keep us in suspense.... opcorn:opcorn:

 

[Roadster Renovations]

Still in the planning phase. I will let you guys know as it develops.

 

[den1953]

I'm Thinking

Along the lines of something like a mudflap that has something like those stone guards on the the back of motorhome RVs that pull a small car. The thing has brush-like bristles that hang down from it and keep stones and chips from flying up and chipping the paint on the car being towed. Just thinking it through here.

 

[Roadster Renovations]

I will give a hint. Look at the rear of the front fender. I can see no reason why they stopped it 5" of the ground........

 

[coz]

Great name for a rock band.:roflblack:

 

[PistonBlown]

As a number of riders here will testify the biggest issue is newly laid chip and tar. The tar helps the chips stay stuck to the tire and they then get flung against the shock etc and bounce around like a pinball. Two local riders both had holed belts for this reason on a single ride. Both riders had the 'missing stone guard' fitted so unfortunately this wasn't enough. One of them did come up with a solution nicknamed the 'Muzza guard', he produced a few and was selling them on trademe (our version of ebay) but I've not seen them recently.

 

[Chupaca]

None of the above....

Gremlins..!! Get a bell..:roflblack::roflblack: there is a great deal of commotion going on under there and if in the less traveled areas slow will be your best bet. :thumbup: