Bicycle Mechanics - V brakes wearing fast

so ive had my bike for just under 3 weeks, not even riding it that much, maybe 3-4 miles a day with couple longer rides.
the rear bakepads are completely worn through to the point where i cas see some metal and am concerned for my rim!
is this normal fo rV brakes, they are the shimano generics I think since they dont say deore or tektro or anythin on em, just shimano v brake.
as the bike was not a cheap model, i expected there to be more quality to 'em.
could there be another issue causing the rapid thinning of my break shoes? i have noticed alot of fine grey powder acumulating on the rims, i am assuming this is coming from the brake pads....

You are right to be concerned but its not your brake pads wearing fast. Its your rim. Standard brake pads are usually to hard and yes, it is common for them to collect shards of metal from the rim which then do more damage to the rim.

The quick fix is to pick the metal shards out of the pads, sand them lightly and also sand the rims lightly. Longer term it is recommended to get some softer brake pads which are easier on the rims. Koolstop pads are recommended.

Anthony

Shimano pads are pretty good and will last far longer than what you are seeing. They also don't wear rims abnormally. Check the brake alignment to be sure one pad isn't rubbing all the time. Something is seriously wrong with your bike and unless you can diagnose it, take it to an LBS for help.

hmm, ive also noticed that the brake shoes seem to be wearing at an angle, so they are not hitting the rim parallel to each other.... cant figure out how to adjust this though...
the pads are definitely worn down to the metal, so i need new ones, i will go with the koolstops and see how they do.
hmm, i wonder if i can find a bike shop open on xmas in the dc area....

Open shop on Christmas? Doubt it -- if I had a shop I'd be giving everyone the day off for family time. Maybe if you found one staffed by Jews or Buddhists or something.. ;)

How-tos:
http://parktool.com/repair/readhowto.asp?id=21
(from http://parktool.com/repair/bikemap.asp )
http://bicycletutor.com/adjust-v-brakes/

hmm, ive also noticed that the brake shoes seem to be wearing at an angle, so they are not hitting the rim parallel to each other....

They are usually adjusted so the front of the pads hit the rim first to help reduce chatter.

hmm, ive also noticed that the brake shoes seem to be wearing at an angle, so they are not hitting the rim parallel to each other.... cant figure out how to adjust this though...
the pads are definitely worn down to the metal, so i need new ones, i will go with the koolstops and see how they do.
hmm, i wonder if i can find a bike shop open on xmas in the dc area....

Its normal and desirable for the brake pads to be angled. Its called toe in. The brakes are much more likely to shudder and squeak without toe in.

I have NEVER heard of standard brake pads wearing that fast based on your usage. I definitely have seen new brake pads damage the rims however and pick up shards of metal from the rim. Are you saying that the brake pads are worn right down to the pad holder on the side?

Anthony

I've worn rim pads out quickly during a single mountain bike race in nasty wet gritty conditions with over 6000' of descending, so wonder what conditions your mileage is in? Funny that your rears go first, unless you use your rear brake primarily for some reason? Sounds abnormal in any case, like the others have suggested otherwise...

FWIW, if the brakes are out of adjustment and one pad touches the rim all the time, premature wear can be expected.

It's simple to fix, though. That's why I put up those how-to links.

so ive had my bike for just under 3 weeks, not even riding it that much, maybe 3-4 miles a day with couple longer rides.
the rear bakepads are completely worn through to the point where i cas see some metal and am concerned for my rim!Can you post some pictures of said pads? Metal in the pads just means that it's flakes coming from the rim. Pick those out. Worn is based upon measuring the thickness of the pads.

Sounds like Anthony is right -- galling. I thought I had worn the pads, too, but it was a piece of my rim stuck in the pad. My stock Tektro pads were sawing up my rims. It got to the point where I was sanding those things everyday.

Kool Stops from Velo Orange made everything better. They even stop quicker. I got them for $10 a set with quick and cheap shipping. Can't beat em for a cheap fix.

I can't think of any condition that would wear out pads completely that quick... so it's likely that what the other guys are saying about the pad picking up some rim metal is the case.

But if by chance the pads have really worn down to metal, tell us more... I'm really interested.

Most pads would have to wear down roughly 6mm before they're well and truly shot, and that takes a fairly long time to happen. Although, it's possible under severe conditions. My worst experience was a half day mountainbike ride over abrasive riverbank clay in the rain with a lot of mud-puddle crossings. That trip took down my pads down to half and left a lot of dark grey residue, which I'm pretty sure was half the thickness of my alloy rim wall thickness!

I would take the bike to your LBS as soon as they open and see if they can sort that out as part of the warranty, seeing as the bike is new... and not a cheap one at that. Even if it was galling, it doesn't seem right or normal for a 3 week old bike... :(

hmm, I was under the impression V brakes do not need any toe in...
in any case, I had a look at the pads, and it does indeed seem there were bits of aluminum from the rim stuck in them. I rubbed them out, but i do notice the pads are wearing inevenly. i have studied the parktools website on V brake adjustment and done my best. It seems better now, but the rear pads were worn quite a bit, and at an angle at that.
I am waiting for some koolstop pads from the USA, hopefully this will help. Going back to the bike shop is out of the question for now, as it is in Oxford, UK, and I am in Chiapas, Mexico!

You really shouldn't be getting constant metal on your pads, it usually means one thing - your pads are shyte.