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Old 05-23-07, 08:04 AM   #1
Collie
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slight clicking/pulsing when i pull the FRONT BRAKE to slow down???

hi there,

i recently built a touring bicycle and i am currently ironing out any issues.

i have noticed that there is a pulsing feeling in the handlebars when i pull the front brake.
my guess is that it is related to the fork steerer/threadless headset and the steerer tube.
i thought that the headset wasn't tight enough, so i opened it up and retightened it again, but i still have a slight pulsing when i slow from speed using the front brake, like a tick, tick, tick, tick, and so on.

it is a thorn sherpa frame and fork, but it feels as if there is slight play/movement between the two (fork and frame) diameters.

any ideas? or tips?

thanks
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Old 05-23-07, 08:18 AM   #2
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Just based on your feel of play in the headset I would go with tightening up your headset some more. Sometimes your front can pulse if you have a rim trueness (or dented) problem, but I'd continue to tighten the headset, at least until it's just short of binding.
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Old 05-23-07, 08:20 AM   #3
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Well, if there's any play between the fork and frame, you do indeed need to tighten the headset. You can check for sure by holding the front brake and rocking the bike back and forth to see if the fork moves independent of the frame.

The repeating tick sound, however, does not sound like it has anything to do with the headset. If I had to guess, I would say it's some sort of inconsistancy in the rim surface such as a weld or a dent. I've had those sorts of things and ridden on them for many thousands of miles, so check the braking surface carefully and if nothing jumps out at you, you're good to go.
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Old 05-23-07, 08:57 AM   #4
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My guess is that this pulse/click coincides with the seam on the wheel.

With masking tape, flag the spoke closest to the seam and go for a ride, test the brakes and see if you don't get the pulse when the tape is at the brake caliper.
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Old 05-23-07, 09:09 AM   #5
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To me this sounds more like an out of true wheel and loose spokes. And, of course, there should be no slack in the headset, but on the otherhand be careful not to over-tighten the headset.

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Old 05-23-07, 10:35 AM   #6
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^^^Agree, I think it's in the wheel. I think Stacey is right on about the seam. There's another factor to look at too, and that's the front brake. I had a bike with cantilever brakes that had enough play that every time the rim seam passed under them, they'd click on their mounting posts. It was an inherent design problem, couldn't be corrected. Eliminating rim irregularities was the best cure. And do be careful not to overtighten your headset. If it's too loose, you'll feel a kind of thumping as you rock back and forth. There will always be a *trace* of back and forth movement where the fork meets the head tube, just a trace. No knocking or thumping though.
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Old 05-23-07, 10:55 AM   #7
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+1 for Stacey. At least the first, and easiest, thing to rule out.
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