Hydraulic Brakes

LeighK123

Hi Guys,

Basically bought some hydraulic brakes a few weeks back. Got it aligned and everything sorted, no rubbing at all. Went out on my local trail today, had a puncture in the rear tyre so had to patch it up etc, then attach the wheel back. However, there is now slight rubbing on the disc brake pads?.

I do not understand this, because if seated properly (i have checked that it is), the wheel should be in the same position within the caliper as before, and therefore there should be no rubbing at all. However, after patching up the tyre, and attaching it again, there is now slight rubbing.

Is it normal to do this?. I cannot be bothered removing the bolts and aligning the caliper again, just for me to do it every time i puncture and remove the tyre?.

What would you do?

Just to remind you, they are new break pads (Done about 60 miles now).

Thank you for your help.

Leigh.

nicklouse

Yes as it will not be exactly in the same place. Just go ride it will bed in again.

And Brake.

John Wh

My last bike had a QR rear and this used to happen to me a lot. I found it far quicker to just slacken the caliper bolts, squeeze the lever (with the wheel in the dropouts), then just nip them up while the brake is tight.

Used to take about 30 seconds.

larkim

Or alternatively, whenever you remove the wheel press the pads back into the max position with something non-damaging to the pads, and they'll re-set themselves assuming the caliper was well set in the first place. I'd be less of a fan of messing with the caliper bolts in case the threads wear and get stripped.

Or does this sound like nonsense?

The Rookie

It can take the pistons a while to settle, so pushing the pads back may mean cr@ppy braking for a few miles, so I wouldn't, as for stripping the thread, you either are a ham fisted oaf and do, or you don't, doing up a thread a few dozen times properly has no effect.

John Wh

As long as you're not swinging off the bolt, then it will be fine.

larkim

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19699653#p19699653]The Rookie[/url] wrote:

It can take the pistons a while to settle, so pushing the pads back may mean cr@ppy braking for a few miles, so I wouldn't, as for stripping the thread, you either are a ham fisted oaf and do, or you don't, doing up a thread a few dozen times properly has no effect.

Must be a ham fisted oaf then!

My only experience with this is on my Suntour crappy forks I swapped the shop fitted Hayes brakes for some recently acquired Shimano hydraulics, and after three tighting / loosening cycles (whilst I got things centred properly) I've now got a bottom bolt which is happily rotating in the fork lowers. I am the weakest of the weak when it comes to tightening things up, I just used a 4cm long allen key (so not excessive torquing forces possible in my puny hands!).

Perhaps it is the crappy Suntour forks. Perhaps it was a badly installed set of brakes by Decathlon in the first place. But it certainly felt to me that I'd stripped the threads without any great effort!

As for pushing the pads, my (limited) experience was that a few squeezes of the brakes and a couple of hard stops were all it took for the pistons to get themselves back into a decent position, but perhaps that has much to do with me getting the centring wrong in the first place!

The Rookie

Fork may have been defective or you may have cross threaded it which then significantly weakens the thread!

larkim

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19700519#p19700519]The Rookie[/url] wrote:

Fork may have been defective or you may have cross threaded it which then significantly weakens the thread!

Indeed, having cross threaded stuff in the past I know how (and how not) to cross thread!

Just thought I would share my experience - Suntour forks are not great, I know that, so defective is my presumption.

cooldad

Suntour are used on millions of bikes with no problems so I would say ham fisted oaf.

larkim

:-)

It's a badge I shall now wear with pride, as you wouldn't think that to look at me!