2001 EV-Black powder on rear rim

[drburt]

Black powder on rear rim and spokes.
Non greasy. Dry.
What is it?
Soot from exhaust (doesn't smoke)?
Rubber from tire?
Inquiring mind wants to know.
Thanks!
Brent

[fotoguzzi]

Brake dust. Do you use the foot brake a lot?

[drburt]

I'm not sure what a lot would be.
I don't ride the brake.
I live in the flat lands of the Panhandle of Texas with minimal curved roads.
I do ride it a bit in town.
I use it more than the front brake to avoid front end dive at stops.
The powder seemed to start after I began to rev it higher (flog?) after I got used to the bike .
Of course, that would take a whole lot of funky turbulence for exhaust soot to make its way forward to the wheel!
Thanks,
Brent

[Madtownguzzi]

Cush drive rubber might be dried up and disintegrating

[pehayes]

If there were enough tire rubbing to create a dust coating, you would likely see a similar loss of paint at the contact point on the inner face of the swingarm and/or driveshaft tubes.  Have you removed the wheel for inspection?  Any degredation to the tire sidewall where it nears the swingarm tubes?  Did you recently boost your tire pressure for some reason?

Patrick Hayes
Fremont CA

[Tom H]

My '04 gets black dust on both front and rear. From what I believe it to be brake dust. If I clean the rim to shiny chrome, it comes back in a month or so of riding the longer I go without cleaning, the more it looks almost like a flat black powder coat. Actually, thought about paint or powder to make it look like that all the time!

Tom

[drburt]

All possible causes.
Even if it's a natural sign of brake use I need to replace rear brake pads anyway.
Cush rubber an interesting thought. I'll check them out when I remove the rear wheel for inspection.
Tire rub was one of my first thoughts.
Looking at the tire I don't see any wear on the sides where it could be rubbing the swingarm or the ridiculously close center stand.
I'll check the possible rub spots when I remove the wheel.
No increase in tire pressure.
I do have a bit on the front wheel also, but nothing like the rear.
Hmmmmm...
Thanks for the input guys.
Brent

[fatbob]

It’s mostly tire wear, and also just road scum.   That’s why the rear wheel gets more of it than the front.  Road scum gets kicked up by the front tire and accumulates on the rear.  It’s not brake dust. 

[Tom H]

From the year, I would guess that you have linked brakes like my '04 EV T. I changed to shorter shock and messed up the brake bias valve due to the shorter shock. Went through a rear set of pads fast compared to front. Did you put shorter shock on?

Tom

[drburt]

I bought the bike used and I don't know if the shocks are stock or not.
Not sure how to tell.
I'll check them out and see what I can tell.
Thanks,
Brent

[Mr Revhead]

Those wire wheels look good, but my god they are hard to keep clean! Sounds like brake dust, try and clean it off regularly, it can eat into the chrome.

[Vagrant]

It�s mostly tire wear, and also just road scum.   That�s why the rear wheel gets more of it than the front.  Road scum gets kicked up by the front tire and accumulates on the rear.  It�s not brake dust.

This! you can tell by the feel of it.