Trouble setting up brakes (resolved)

mikelskas

Hi guys,

As the title suggests I am having trouble setting up the brakes on my 2007 Specialized Langster.



The brake pad on the side not shown lines up perfectly with the rim but no matter what I do I cannot get this side to line up. If I continue using it as you can see it will eventually score the tyre and wear it through.

Things to note:

I cannot move the wheel closer as the chain will be too slack.
I cannot take links out of the chain because then the chain wont reach around the gear and chainring even if the wheel is as close as it can be.
The wheel is definitely correctly alinged within the chainstays.

Is there something obvious I am missing?

n1ckster

Is the brake block located in a similar position on the caliper as the one shown?

Nick

mikelskas

Nick,

The brake block that is not shown (left hand side) sits perfectly on the rim and is in no danger of touching the tyre.
Both blocks are as low as they can go within the caliper. I even switched from a 16 tooth rear wheel to a 17 so the wheel sits slightly closer.

n1ckster

The only thing I can therefore suggest is that your frame requires that you use deeper drop calipers. This would give a greater range of adjustment of the brake blocks (up and down) once the calipers have been centred.

I'm not aware of the number of teeth on your cassette having any significance to your brake alignment issue. The axle is always at the centre of the rim and all the spokes to the rim are the same length, so assuming it (the wheel) is fitted into the rear dropouts correctly, it always places the rim in the same place, relative to the brake calipers.

Nick

mikelskas

I know long reach calipers would work fine but I dont want to spend any more money on this bike as it is a work hack.
The calipers should fit fine as they are same ones that came with the bike when it was new. I wasnt the original owner though so I cannot comment on how they were originaly set up.

With it being a single speed, if I switch from a 16 tooth cog to a 17 the rear wheel has to be moved closer to the bottom bracket so the chain can fit around the new larger tooth cog. Its only 5mm or so but every little helps.

nweststeyn

n1ckster wrote:

I'm not aware of the number of teeth on your cassette having any significance to your brake alignment issue. The axle is always at the centre of the rim and all the spokes to the rim are the same length, so assuming it (the wheel) is fitted into the rear dropouts correctly, it always places the rim in the same place, relative to the brake calipers.

The langster has horizontal dropouts, which change the position of the wheel in the frame.

pinarellokid

are both wheels like this??

for the price of a cheap single caliper (£25) id just buy on e and away you go.

mallorcajeff

just a thought is the brake pad in the wrong way up? undo the allen bolt holding it on and try rotating it 180 degrees its not gone back the wrong way round when you adjusted it has it?

mikelskas

Brake pads definitely the correct way up.

But good news guys, I borrowed a chain checker from a friend and found the chain is worn way past the .75% mark.

The extra wear on each link of course means the rear wheel has to sit further back in the frame to take up the extra slack. Fingers crossed a new chain will solve everything.