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Old 10-15-09, 12:15 AM   #1
eerickson7
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Brake pads too high

I got a set of medium reach front brakes for my fixed-gear bike. It turns out they're just a very, very small amount too high when they're all the way at the bottom of the brackets. One of the pads rubs on the tire when I apply the brakes (except real soft braking).

Now I see that some of the little metal threads in the sidewall on one side are starting to become visible.

Any cheap/easy ways to deal with this? I thought if I could find a slightly narrower brake pad, that would take care of it. But I don't want to start buying different brake pads and installing them only to see no appreciable difference. I don't see any dimensions listed for brake pads on the internet, and I don't think I could eye a 2mm difference when shopping for brake pads.

The brake in question is a Shimano BR-650.
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Old 10-15-09, 12:25 AM   #2
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Don't continue using the existing setup because you'll damage the tires causing a blowout.

The best, though not the least expensive solution is to find a longer reach brake, or possibly a drop bolt for your existing brake which will lower the range by 5mm or so.

I doubt you'll find shoes with enough difference in thickness, but you can use a coarse file to shave some off the top edges of the current shoes. Otherwise, if you don't need too much extra drop you can use a rat-tail file to extend the slots in the calipers by a few millimeters.
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Old 10-15-09, 01:12 AM   #3
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Dia Compe and Tektro offer brakes with very long reach. I use such on my 3-speed. Hunt around if you don't want to mangle the Shimano's.
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Old 10-15-09, 01:19 AM   #4
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Thanks for the help. I am very cheap, so I'll probably try some combination of altering the pads and/or shaving out a little extra room at the bottom of the brackets. I measured the distance and it was right in between medium reach and long reach. I apparently chose wrong.
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Old 10-15-09, 01:25 AM   #5
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Take a small circular file and file the bottom of the brake-pad slot on the caliper. If you need to move the pads down 2mm, extend the slot downwards by 2mm. You just need to leave barely enough metal so the two sides are connected. There's usually enough room to move the slot down by up to 4mm on most brakes, some allow even more.
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Old 10-15-09, 06:57 AM   #6
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Take a small circular file and file the bottom of the brake-pad slot...There's usually enough room to move the slot down by up to 4mm on most brakes, some allow even more.
This is what I do. Works fine and save $$. If I need more drop after filing the calipers to the max, I file the pads too. We did this all the time back in the 70s when someone wanted to put sew-ups in a 27" wheeled bike, never had any issues.
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Old 10-15-09, 01:44 PM   #7
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could try filling the fork drop outs a bit. ussually lots of metal there.
so the wheel sits nearer the brake.
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Old 10-15-09, 02:10 PM   #8
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could try filling the fork drop outs a bit. ussually lots of metal there.
so the wheel sits nearer the brake.
that should only be the option of last resort. First it's harder to file steel 6mm of steel vs 3mm of aluminum, but more important is that filing the dropouts will effect how the wheel sits in the fork, and would need to be cone fairly precisely to avoid changing the tracking of the bike.

Usually I suggest filing the dropouts only to correct a defect whereby the wheel is not in plumb.
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Old 10-15-09, 06:59 PM   #9
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could try filling the fork drop outs a bit. ussually lots of metal there.
so the wheel sits nearer the brake.
This is seriously the worst advice I have read this month on bikeforums. Do not do this.

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that should only be the option of last resort. First it's harder to file steel 6mm of steel vs 3mm of aluminum, but more important is that filing the dropouts will effect how the wheel sits in the fork, and would need to be cone fairly precisely to avoid changing the tracking of the bike.

Usually I suggest filing the dropouts only to correct a defect whereby the wheel is not in plumb.
It's not an option, period for the OP's case.
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