Bicycle Mechanics - Incredible brake wear in 1 day!!!!

I was biking in the city, in the rain today for about 5 hours. I noticed that my brake power was continually being reduced. Upon closer inspection of the brakes I noticed that a) There was grey crap all over the braking surface and b) that the breaks has lost several mm in profile since the morning. I really cant figure out why this would happen. The wheel isn't rubbing against the pads and this happened in the front and the back.

Maybe you just picked up a bad batch of pads. Could be defective compound that just disintegrated.

How probable is that?

I had the same problem on my Lemond with Ultegra brake pads.

It's the only explanation I can think of unless someone happened to have dripped something corrosive onto your pads. I'm thinking that the pads were fine until you hit a certain depth that exhibited poor manufacturing and maybe it started to chunk off. You may not have noticed it right away and then the roughness got smoothed over/glazed with subsequent braking so it just looks like you had a quantum leap in wear.

It seems to have happened on both the front and the back (but more so on the rear). What is the likely hood that there was a defect on both? Is it possible I took up something corrosive from the road surface?

Did you replace the brake pads at the same time? Yes, it's quite possible you picked up something corrosive. How do your tyres look? How about your paint finish? Is acid rain really getting that bad now?

Brake pads both came with the bike. The tires are brand new and look find except for having all this grey break dust (I assume) all over the sidewall. Frame looks fine.

This is like what started to happen back in Love Canal. ;)

If you were riding in the rain, you were riding in the mud. All that water coming off the street had particulate matter in it -- dirt, grit, petroleum products, fertilizer, whatever. All dissolved into a nice suspension just perfect for wearing out your pads.

Get Kool Stop salmon pads. They resist this sort of thing a lot better than most OEM pads, particularly Shimanos.

RichC

Whatever the abrasive substance is, if it took that much off the pads, it possibly took some off the rims as well.

Might be wise to check the braking surface of both rims for excessive wear too.

I think I read on a Shimano instruction pamphlet that their pads do indeed wear faster in the rain. From experience, I would agree with that. I use Durace pads in my ultegra brakes (9spd groupsets) since they are marginally cheaper than aftermarket pads anyway. I've used Cool Stops on previous bikes with no complaints, but I like the neat fit, appearance and braking action of the Durace pads. I am not an expert on pads, but I frequently lift the back wheel off the ground during my city rides.:D

The high wear rate when braking in rain is unfortunate, but I can live with it. The real expensive damage is being done to your drivetrain anyway, it takes a while to reveal itself. Rims must suffer from braking in grit-soaked rain, but I think a softer pad must be easier on rims, in general, than a harder pad. Like with cars...hard metalic pads are good for repeated hard stopping but can quickly destroy the steel disks they grip. It's not a small issue...I have an alloy front rim I have deemed unsafe to ride any more due to wear on the braking surface. I've had the same rim fail on the back when the braking surface "peeled off" right in front of my eyes shortly after a fast descent...YES, the metal separated and the tyre blew off with a BOOM!!!:eek:

i was caught in a recent deluge and could not believe how much the shimano pads wore...i too had grey dust all over my rims....going to ride to my lbs tommorow to pick up some kool-stops

Hmmm... I'm using Dura-Ace pads currently and have ridden extensively in the rain (it's unavoidable in the PacNW winters). I have not noticed such increased wear. Perhaps I'm just not having to use my brakes as much as some? I do use them on many of the long downhills here. I usually feather them slightly... just enough to keep them dry so I'll have something to use by the time I'm at the bottom of the mile long 10% hills that surround my house. Perhaps full engagement when they're wet accelerates wear?

why are you braking?! this is on a road bike, right? speed control my @ss...:D

Originally posted by KevinG
I had the same problem on my Lemond with Ultegra brake pads.

I dislike my Ultegra pads as well. I'm gonna pick up a set of Koolstop. I find myself cleaning Ultegra pads way too much.

I guess I should specify where they came from. The pads came with my entry-level Peugeot MTB.

Is that a new bike? I mean, I thought that bike had some good mileage on it when I saw it. If that's the case, they were probably due for new brakes at this point.

Just an observation.

II have had the same wear while riding my mountain bike in the rain on cart paths. I beleive it is normal to these breaks. A lot of the grey crud is actualy aluminium from the rims.

Acid Rain. Burns them up every time.

Originally posted by Koffee Brown
Is that a new bike? I mean, I thought that bike had some good mileage on it when I saw it. If that's the case, they were probably due for new brakes at this point.

Just an observation.

When you rode it there was considerable brakes left from visual inspection. Now there is almost none after one day.

Are you trying to say that I wore down those brake pads?

Them's fightin' words, cannuk!

;)

Are they pads for v-brakes? If so, many are very thin to start with.

Rain by itself isn't a problem, except for the fact it makes braking a little bit harder. However, if you were riding in dust -- say chemin Olmsted -- or if you have been riding on a dusty road yesterday and still had the pads full of grit, then you just had enough abrasives to wear the pads down.

I'm aware that Shimano brake pads wear down fairly quickly and have heard quite a few times that the Ultegra break better in rain... but wear out considerably faster than the "regular" Shimano pads. The Kool Stop Salmon or Dual (not the red, by the way) offer very good braking, even in rain or snow, and don't wear out very quickly.

On my touring bike, the original pads that came with Avid 20 V-brakes lasted 2-3 months, then a set of Shimano pads lasted less than 1 month on the front wheel. I replaced them with Kool Stop Dual compound and keep a set for 1 year in front and 2 years on the back.

I'm not an aggressive rider so I prefer to slow down instead of braking; however, most of my mileage (approx. 5000 km/year on the touring bike) is done in Montréal and the vicinity (i.e. stop lights) and I often pull a trailercycle and a child trailer... which means a good load on the brakes.

Regards,

Koolstops are cool. I used the standard black ones on MTBs, and my touring bike and they last a long-time in wet and gritty conditions. The salmon ones are a bit difficult to source here, but I don't think I really need them as we don't have rain that often (despite what everyone else in the world thinks!!).

R