Specialized Sirrus Rear Brake Issue

seven stars

I have a 2011 Specialized Sirrus Sport. The rear brake has developed a fault where it sticks on one side and doesn't release from the wheel rim after I brake, making it unusable. I've tried taking the brake off, cleaning it, and lubing it, but it hasn't fixed the problem. I've heard that dirty cables/housing can be the issue, but that doesn't seem to be the case here. It seems like the spring needs replaced on one side (although I don't know that for sure).

My question is: is it possible to just replace the spring? And if not, and I need to replace the entire thing, what sort of brake can I get as a replacement? I'm not really sure what's compatible with my bike. The specs say that I have a 'Forged 6061 aluminium, 108mm linear pull' brake, whatever that means.

All help appreciated.

victorcarrera

seven stars wrote: »

I've tried taking the brake off, cleaning it, and lubing it, but it hasn't fixed the problem.

Remove both arms, grease the bushings, springs and braze on's, check that the springs are not broken or worn causing them to slip out of their positions. Adjust centering by tightening the set screw on the side that is closest to the wheel rim and vice versa.

seven stars wrote: »

My question is: is it possible to just replace the spring? And if not, and I need to replace the entire thing, what sort of brake can I get as a replacement?

Yes ( In the unlikely case that it comes to that). Parts or whole units, new or 2nd hand are cheap and easily sourced from online vendors ebay or CRC.

pikefisher

had the same issue with my bike (tektro vee brakes ) tried cleaning and lubing then found there was not enough adjustment in the set screws . the only way i could find around it was to bend the spring a little on one side which seemed to bring them in line a bit better . dont know if this is a good or bad idea but it worked for me . now alls i got to do is replace the unevenly worn pads .

Mr. Skeffington

I would take a look at the brake pads, sometimes if the pads are set too low they can wear unevenly causing the catching that you mention. I'd replace them if they are too worn or worn unevenly.

Other than that make sure that the springs are set in the same hole on the brake bosses each side of the frame, there are usually 3 different holes which are for different tension of the spring.

You said that you have checked the cable thoroughly so that should be fine. Last thing is to use the little Philips head screws in the body of the v brake to fine tune. You should find some good videos on YouTube or a guide to setting up these brakes on the Tektro or Park tools site.

Hope this helps,

Skeff

seven stars

Excellent fellas, thanks for the replies. I'll give it one more shot before looking to replace the brake.

Treason

There could be a number of things that can cause this. I have a Sirrus myself.

Something that has not been mentioned, and which I would say is the primary cause, is the 'spring'.

The spring is infact a strip of stiff wire/metal, which when the brakes are pulled, is flexed. When the brake is released, it 'flexes' back to its default position taking the one side of the brake with it away from the rim.

What you may need to do is take that bit of wire out and bend it with your fingers to a more 'springier' default position.

Nothing will need replacing.

btw, did you get your username from the plough by any chance?

jimsin

Hi, just stumbled across this discussion because I'm having exactly the same problem myself, only in my case the spring has most definitely snapped

Can't find anywhere that sells replacement springs, so figure I'm going to have to buy replacement calipers, but as was the case in the original post, I'm could really do with some help in figuring out which ones would be compatible.

Again on the website is says the originals are 'Forged 6061 aluminium, 108mm linear pull' brake, but Googling doesn't really bring anything up.

Not looking for anything fancy, but being able to stop would definitely be a great help to me just now