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I just bought some new brake pads for my caliper brakes on a bike I am fixing up and when I apply the brake, it takes at least 10 feet to stop no matter how hard I apply them; basically I can't get the wheels to skid even when I try.

I tried tightening the brake pads to be closer to the tire but the problem persists. Is it just the case that my bike's brake mechanism sucks? Or is this a symptom of something else?

Thanks.

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    Could be cheap hard pads.
    – paparazzo
    Oct 13 '17 at 14:36
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    It's probably because the pad surface is too smooth. Quick fix would be to roughly sand the surface of the pads to give them some texture. Also check your rim is clean, and grease free. Oct 13 '17 at 15:20
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    Did you merely slide out the old rubbers and replaced them with new ones? Or did you replace the entire pads, metal and rubber? In any case they would need to be correctly toed-in, meaning that the front end must be slightly closer to the rim than the rear to work correctly.
    – Carel
    Oct 13 '17 at 16:26
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    I assume you have standard aluminium rims but if not of if they are coated, you need to be careful about the brake pads you use. Oct 13 '17 at 18:16
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    Personally I will only use Kool Stop rim brake pads on my own bikes.
    – Criggie
    Oct 16 '17 at 8:39
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There are a few things to do when your brake pads aren't stopping your bike well: -It could just be that they're new and haven't worn in yet, rub some sandpaper against the braking surface of the pad to remove the surface layer. Then use something to clean it to get off the lose rubber and grease from your hand. This can also happen on old pads with plenty of surface left, the pad can "glaze over". This hard layer can be removed in the same way. -Your rim could have oil or grease on it. Clean the rim and the pads with hot soapy water and leave to dry naturally.

If the pads were very cheap you could just take them back if these methods don't seem like they'll work. You might as well try the washing one because you're bit altering anything and they would still take the pads back.

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I will add another answer in for my case. I've changed the break pads (same compatibility resin/organic but the new ones were more expensive than the original). My impression was very negative in the beginning, because the rear brake the new pads stops worse than the old worn brake pads. I went out to test it (burn-in) as the documentation from the shimano says:

  1. Ride your bicycle in a flat and safe area without obstacles and accelerate to a moderate speed.
  2. Operate the brake lever until you slow down to walking speed. Do this only with one brake lever at a time. Be careful when performing this procedure. Always operate your brake lever with moderation, especially when you burn in the front brake.
  3. Repeat steps 1 and 2 for at least 20 times for both the front and rear brakes. While repeating the process, the brake force will increase.

I did this and it didn't change anything, I went to a competition where there were a lot of descending parts of the trace and there I performed the "Burn-in". After few descendings they feel fine. I do not recommend anyone to do this on descendings, but I've trusted my front brake.

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    This sounds like the procedure for bedding in disc brakes, while I think the original question is about rim brakes, because it mentions 'caliper brakes', i.e. rim brakes for road bikes. So I think it doesn't apply to OP, but it would certainly help someone reading this, trying to fix the same problem on disc brakes, so +1
    – Swifty
    May 15 at 19:55
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    Actually, yes. Thanks. "Caliper brakes" are referred to rim brakes on road bikes, as you said. The confusing word here for me is "caliper", because the disc brakes also have caliper. Bicycle brakes
    – mihkov
    May 15 at 21:06
  • Yep, the words overlap, so anyone using a search engine for either style can find the question, and evidently do (8k views). I would think a lot of those readers these days will actually have disc brakes, but may have never heard of bedding in disc brakes so it's good to cover this essential process (there's a modicum of ambiguity in the question anyway)
    – Swifty
    May 15 at 21:47
  • I don't believe we need to break rim brakes in like disc brake pads/rotors. However, the next step on disc brakes would have been to clean off the rotor with rubbing alcohol or similar. That can actually help with rim brakes as well, in terms of getting any contamination off the rim.
    – Weiwen Ng
    Aug 16 at 0:05
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This is definitely a symptom of using modern brake compounds on a steel rim, which could be the case if you are working on a bike you are 'fixing up'. You would check the rim with a magnet and check the brake pads for the words 'for alloy', which are still commonly included on pads.

If this is the case, no matter how well you adjust the mechanism, the pads just won't grip the rim properly. You would therefore source pads intended for steel rims and fit those instead.

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NOT ALL BRAKE PADS ARE THE SAME. The 'rubber" can be of good quality or cheap quality. If the compound is of cheap quality, then no matter what you do there will be less grip. Pity that brake pad manufacturers don't grade the gripping power of their product

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