Nightmare with brakes

pesky_jones

So. Reasonably new specialized hardrock 2012 sport disc - 8 weeks in, and the rear brake looses strength overnight. It still has the power, just only once ive completely squeezed the lever in. At first I thought there might be air in the system, but the break doesnt feel spongey and still has the strength once completely squeezed in.

As i bought the bike from cyclestore.co.uk (mistake to buy online, i know), i gave them a few emails about warranty etc and they responded telling me i had to take the bike to a specialized dealer. So i rang my closest dealer and spoke about the issue, with them telling me that specialized would pay for any parts that needed replacing but would not pay for labour so bascially, they wouldnt do the work. Great.

This was now a week or two of riding without the back brake and i was fed up and took the bike to my LBS and asked them to have a look and see what needed to be done. They have now told me they have never seen the brake before in 15 years they worked there and if i did want it bled, i would need to buy the mineral oil for it. However, they did not think there was air in the system and had instead just adjusted the central cylinder? i havnt got the bike back yet as it is having a service so need to see what effect this has had.

but now i cut to the chase. Seeing as the guys in LBS had never heard of these shit brakes, would it be wise to get a new set of brakes to avoid more problems and if so, what do i look for???

Bike - Specialized hardrock sport disc 2012

Current brakes - Tektro Draco hydraulic disc brake, post mount, 160mm 6-bolt rotor

any advice much apreciated! Cheers

supersonic

Has there been any oil leaks? If not, sounds like the pads need 'advancing' - guide here:

https://docs.google.com/viewer?a=v&q=ca ... 4wLY-D7ntA

pesky_jones

Nope, No oil leaks. Thanks. Will give this a go before i do anything rash.

The Rookie

Your LBS hasn't seen Tektro's.....try an LBS that knows what it's doing!

May not be anything wrong with the brakes necesarily......Manual here http://www.tektro.com/_english/03_suppo ... 024043.pdf

FAQ page available from here
http://www.tektro.com/_english/01_produ ... rt=1&fid=1

Could consider tweaking the reach adjust, sometimes the easiest way to advance the pads is to elastic band the lever back to the bars overnight. The lad has the very similar Auriga's and while they aren't the best, there is nothing inherently wrong with them either.

mcnultycop

MTB_TR wrote:

As i bought the bike from cyclestore.co.uk (mistake to buy online, i know), i gave them a few emails about warranty etc and they responded telling me i had to take the bike to a specialized dealer.

It's not a mistake to buy online, you still have your consumer rights. I wouldn't let them fob you off.

WhipIt

You're sure it's not just pad contamination? Have you had gt85, wd40, fork juice etc anywhere near there? Any greasy fingers near the rotors? That would be my first guess... Cyclestore was great as a lbs so they should be able to help out, at least with some advice over the phone.

The Rookie

It doesn't sound like pad contamination, the brakes work it's just the levers coming back to far from what TR says, pad contamination means no braking but the lever feeling normal.

pesky_jones

Yeah, I don't think its pad contamination as the pads are simply not fully gripping the rotor untill the lever is fully squeezed in.

Cheers

The Rookie

Watch the calliper, can you see the pads moving during the initial part of the lever movement? Now compare to the front....

Most discs you'll see next to no (or none at all) movement, if you do you need to advance them as stated, easiest way is to tweak the rach adjust to give lots of lever travel and then laccy band it to the bars overnight, tweak the reach adjust back once it's OK, a short ride putting some load/movement into them (with reach adjusted to ensure harder braking) will also sometimes sort it.

pesky_jones

I don't completely understand the guide supersonic posted as my brakes dont have "centre point adjustment" or the red plastic spacers it refers to?

has anyone done this before and can give a simple step by step on how to advance the pads on front AND rear brakes? or does anyone know how effective adjusting the reach is as i think they will need a fair bit of adjustment?

cheers for help

supersonic

Pull the levers until the pads are 1mm apart (when pulled). Or use a 1mm spacer in between the pads and keep pulling the lever. Then refit the wheel.

pesky_jones

probally a dumb question so go easy but im not really following...i pull the brake the lever untill the pads are 1mm apart... and then what? surely they'll just go back to what they were like originally when i realease? do i make some sort of adjustment to the calliper when ive pulled the lever untill the pads are 1mm apart?

apologise for being so slow...

Cheers

bennett_346

MTB_TR wrote:

surely they'll just go back to what they were like originally when i realease?

nope.

supersonic

They 'advance' - open braking systems auto adjust, retracting the pads a set distance each time. So if you push them further out, they will retract to a closer distance than previously.

Is better if you use a spacer as you can pull the levers hard, and you won't close the pads together completely.

The Rookie

Check your cutlery drawer, you may well have a knife blade the right width!

konadawg

Assuming you have accurately described the condition - very long lever travel before the brakes subsequently function perfectly - and any adjustments available have been adjusted - then I'm with supersonic on this.

Probably the piston seal is not "letting go" of the piston (or the calliper cylinder - depending on where it is fitted) and hence retracts the piston far too much when the lever is released.

Pushing the pistons all the way in, and possibly a bit of silicone spray (pads removed!) often helps as it forces movement.