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Old 01-22-09, 02:13 PM   #1
PaulRivers
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Disc brakes rubbing on brand new bike, bike shop says it will fix, but...

So I was shopping for a new bike for winter biking, and found a 2008 Civia Highland on clearance. It comes with all Alfine stuff - internal hub, alfine disc brakes, etc.

So I went to pick up my bike after it was "ready", and being that it was a new bike with a new weird hub and different front dynamo hub, asked the guy to give me a demonstration of how to take the wheels on and off in case I got a flat.

So we took the front wheel off, then I tried to put it back on again. Well, after finally getting it back on on the bike stand the front disc brake is seriously rubbing. I mean, metal on metal sounding. So the guy I'm working with asks another mechanic who apparently is very good with disc brakes to take a look at it. Well, this 2nd guy fiddles with it for about half an hour and can't quite get it right. It's the end of the day, and he says that I should leave the bike overnight and they'll pop off the rotor and put the rotor in some sort of truing stand. He also mentions that the back brake looks good, but in addition to the front rotor being slightly warped, he mentions something about adjusting the front brake all the way over and it still isn't quite right on (while the rear brake is adjusted relatively center to get it to the correct position).

I don't own any other bikes with disc brakes - this is my first one (it's hydraulic). But my dad's mountain bike has also always had a problem where after he pops off the front wheel and puts it back on again (to get it in and out of the car) the disc rubs a little. Like, enough that he can tell while riding it.

So here's my question - is the brakes rubbing after taking the wheel on and off something that's common with disc brakes? Or if I still have this problem when I pick up my bike, should I insist that they replace the rotor or the brakes? Can they really "true" the rotor? Or is the brakes rubbing just something I'm stuck with with any bike with disc brakes?
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Old 01-22-09, 02:25 PM   #2
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Rotors warp and need truing, just as wheels do (although now that you have disc brakes you'll need to do wheel truing less). It's easy to do, tools can be as simple as a small adjustable wrench and your eyes, or you can use a runout gauge and special tools; you should be able to do this for yourself (after your bike shop won't do it for free). As far as readjusting or recentering the caliper, as it sounds like they might need to do that, that's all dependent on the quality of the original install. I'm not familiar with your particular bike or brakes or the quality involved.

I've never had a problem getting my wheels back in exactly in the same place on my bikes in general, don't know if that's more due to the tolerances of the wheel/dropouts involved or the technique of the person replacing the wheel, but have read many people have this problem.
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Old 01-22-09, 02:45 PM   #3
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In my experience, it is best to push down pretty hard on the stem of the bike while tightening the front wheel QR. This seats the axle all the way into the dropout. Try to always tighten the QR to the same tension and keep it in the same position so that the same load is on the forks and they will deflect in the same way (therefore keeping the disc in the same relative position to the caliper). Discs require a lot of force to slow the bike down, which means that slight rubbing will be more of an annoyance than an actual performance loss.
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Old 01-22-09, 04:40 PM   #4
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Try to always tighten the QR to the same tension and keep it in the same position so that the same load is on the forks and they will deflect in the same way (therefore keeping the disc in the same relative position to the caliper).
+1. Try to figure out which pad is rubbing, and alter the QR tension accordingly. If the outer pad's touching, you need less tension. If the inner pad's touching, you need more tension. (I think I have that right).

Of course, if once you get it to stop rubbing the QR tension is outside acceptable tolerances, that might indicate an installation issue.
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Old 01-22-09, 05:35 PM   #5
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Hydraulic or mechanical? Sometimes hydraulics accidentally get squeezed with no rotor in place, requiring the pads to be reset(pried apart). I suspect that the caliper was installed while the wheel wasn't totally bottomed out in the dropout. If it were me, I would just reinstall the caliper after making sure the wheel is in properly. Truing the rotor is much simpler than it sounds- I just use my bare hands. OTOH, I've never seen a set of alfine disc brakes.
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Old 01-22-09, 05:43 PM   #6
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They're hydraulic brakes as I mentioned.

The bike is still at the shop. The shop *claims* they fixed it. I'm going to try taking the wheel on and off and seeing if they start rubbing again.

The bike costs $1700 before taxes or accessories, so I have to decide if I even want to accept it. I'm a little worried the problem is somehow caused by a bad fork mount, a badly installed brake, or a defective brake. For this kind of money...wouldn't you think it's fair to ask that the bike not have defective parts? :-( I'll certainly take your suggestions like making sure the wheel is set in the fork fully when I'm trying it out.
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Old 01-22-09, 06:02 PM   #7
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Don't worry too much. Most new bikes require a little bit of tweaking initially. At that price, I would be surprised if there was an issue that the shop wouldn't be glad to take care of.
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Old 01-22-09, 07:07 PM   #8
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If you had trouble putting the wheel back in the forks the rotor may have been warped while you were putting it back in place. But, disc rotors and their calipers have very tight tolerances for clearance, so a little rubbing is unsurprising.
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Old 01-22-09, 07:51 PM   #9
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If a hydraulic brake system on bicycles have the same principle as in auto/motorcycle, the brake pads are always touching the rotors,but the wheel can still turn freely, just my 5 cents,inflation,u know?
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Old 01-22-09, 08:24 PM   #10
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If a hydraulic brake system on bicycles have the same principle as in auto/motorcycle, the brake pads are always touching the rotors,but the wheel can still turn freely, just my 5 cents,inflation,u know?
They do work about the same, but they can be set up so that they don't rub. Rubbing is fine on a car or motorbike because of the already loud noise. Bike discs usually have about .5mm of clearance on both sides so it doesn't take much for them to rub, but it is possible to keep them from doing so.
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Old 01-22-09, 08:33 PM   #11
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I have the Civia Hyland Rohloff which has the same Alfine front rotor and caliper as the Hyland Alfine and I have not had any problems. I do always make sure that the wheel is fully seated in the dropouts. Sounds to me like your LBS does not know disc brakes too well. I had my LBS order the Hyland Rohloff for me after talking with the owner who also has a Rohloff hub bike.

I really like it so far and just upgraded he generator headlight to the latest Lumotec, the IQ Cyo Senso Plus.
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Old 01-23-09, 02:43 AM   #12
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They're hydraulic brakes as I mentioned.

The bike is still at the shop. The shop *claims* they fixed it. I'm going to try taking the wheel on and off and seeing if they start rubbing again.

The bike costs $1700 before taxes or accessories, so I have to decide if I even want to accept it. I'm a little worried the problem is somehow caused by a bad fork mount, a badly installed brake, or a defective brake. For this kind of money...wouldn't you think it's fair to ask that the bike not have defective parts? :-( I'll certainly take your suggestions like making sure the wheel is set in the fork fully when I'm trying it out.
Who says it has any defective parts? Perhaps the brake was not installed well, that's possible with any bike, let the shop deal with it if you can't.
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Old 01-23-09, 02:29 PM   #13
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Who says it has any defective parts? Perhaps the brake was not installed well, that's possible with any bike, let the shop deal with it if you can't.
YOU'RE the only person who said it had defective parts. I said "I'm a little worried the problem is somehow caused by...(defective parts)".

I also blatantly said I already asked the shop to take a look at it. In the exact post you quoted.
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Old 01-23-09, 03:36 PM   #14
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I have the Civia Hyland Rohloff which has the same Alfine front rotor and caliper as the Hyland Alfine and I have not had any problems. I do always make sure that the wheel is fully seated in the dropouts. Sounds to me like your LBS does not know disc brakes too well. I had my LBS order the Hyland Rohloff for me after talking with the owner who also has a Rohloff hub bike.

I really like it so far and just upgraded he generator headlight to the latest Lumotec, the IQ Cyo Senso Plus.
fyi, here's what happened - after the mechanic spent some time working on the brakes, they wouldn't rub initially but after removing and putting the wheel back in again, they would rub again (though not nearly as bad as the first time I did it - the first time sounded like metal on metal nearly, this time it was more of the traditional brake pad rub). The sales guy I was working with tried it to, and one time the pad would rub on the right side, the next time it would rub on the left side and he could see it rubbing.

We figured out it would stop rubbing if you put the wheel on with:
1. The quick release pointing away from the fork. One of the times the sales guy fastened the wheel on with the quick release against the fork, and the fork seems to be to fat so the quick released wasn't really 100% closed.
2. The dynamo connector pointing slightly backwards from the fork. If it pointed straight up the fork it seemed to be a problem.

Watching these 2 things, I was able to take the front tire off and put it back on several times without the disc brakes rubbing. I did the same routine with the back wheel, but never had any issues with that one rubbing.

To tatfiend - do you live in the US? I ask because I'm also getting the IQ Cyo Senso Plus installed on my bike, but they ordered it and it doesn't sound like it will be here until mid-February, so I'm curious how you already have one. :-)

I really thought the Shimano light seemed as useful as one of those $30 AA bike shop lights - yech. I guess it would work for "be seen". I kinda like idea of the blinky light on the top of it, but only if I could actually turn it off, which you can't. I also have to buy a new front light in order so get the dynamo powered rear light, which is what I initially wanted (I've become more enthused about the dynamo front lights having seen the beam shots - they look like actual "see by" lights!) I also liked the looks of the Supernova E3 with the asymmetrical beam which will cut off light above the horizon, but it was just to expensive - to expensive on a bike I'll leave locked up outside coffee places and work, and even more expensive when you consider that (supposedly) only their particular tail light will work with it, and that costs $70 vs. $35 for the B&M one.

Did you get the Cyo with the taller beam that lights up the area right in front of the wheel, or the other one that's brighter, but has a gap between the light and the front wheel?
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Old 01-23-09, 03:46 PM   #15
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YOU'RE the only person who said it had defective parts. I said "I'm a little worried the problem is somehow caused by...(defective parts)".

I also blatantly said I already asked the shop to take a look at it. In the exact post you quoted.
Uh, no, I didn't say it had defective parts, that's your conclusion. Warped rotor isn't defective, it just needs truing (if that's actually what it is). Sometimes calipers aren't installed properly, sometimes the pistons can be a bit sticky, but neither means it's defective.

In any case glad you guys figured out how to install a wheel with a quick release
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