Lack of Cantilever Brake Power

[scottz123]

2010 Ridley X-Fire with TRP EuroX Cantilever's with Kool Stop Salmon Pads, Mavic Kysrium wheels - rear brake has hardly any braking power

I bought bike used last fall with trp cantilevers on it. This spring I installed TRP 'inplace adjust' http://www.trpbrakes.com/category.php?productid=1034&catid=187&subcat=0 along with Kool Stop Salmon pads.

Initially braking was much improved.Seem like's power has declined. At one point, I could lock up rear - now rear braking power is not there, almost like no brakes in rear. Yes, I have read Sheldon Browns articles on setting up cantilever brakes.

Any other tips or hints before I throw another set of pads at it? I have tried scuffing brakes w/sandpaper and cleaning rim surface w/ brake clean.

Rear Pads have a lot of material on them - they seem almost new. Could pads have been old and hardened to begin with?

Thanks in advance

 

[alfeng]

TRY shortening the length of the straddle cable ...

• if YOU think that the straddle cable is the "proper" length, then post a picture which includes the brake & cable & yoke & hanger as they are currently adjusted on your bike

Also, ensure that the brake cables & housing have-been-and-are properly lubricated.

 

[scottz123]

Thanks for your assistance! Top pick is rear brake, bottom is front. I allready tried shortening straddle on both in spring, but on rear, I ran out of brake cable. I will give that a try, with longer brake cable.

I thought power was improved after making changes in spring - but power has deteriorated since adjustments in spring. Since original post, I cleaned rim surface w/ simple green mix and scotchbrite pad and used nail board on brake pads. Then wiped clean with nail polish cleaner (acetone). Power was improved, but resulted in squeel (i had no toe in on pads). I added toe in to pads and squeel went away along with a little braking power.

PS: I live in midwest and deal with mud @ CX races, so I cannot shorten straddle to much. Any 'rule of thumb' you know of for straddle length with mud?

Thanks in advance

 

[alfeng]

FWIW. On your CX frame, I would look at (measure) the clearance at the BB and/or chainstays & use THAT as the maximum "tire" clearance which the frame allows ...

For cantilever calipers which have shorter arms, I'm guessing that an angle of about 90º when the brake levers are in a neutral position is probably the preferred starting place (so, your front straddle cable looks "okay" EVEN THOUGH you have long arm calipers, but if you want a slightly quicker response, then you'll obviously need a longer cable OR to shorten the cable housing [which may not be feasible]) ...

I would MOVE-or-USE the current, rear brake cable for the front calipers & buy a new cable for the rear calipers ...

So, with the long arm cantilever calipers (without-knowing & regardless of the clearance at the BB) I would try lowering the rear YOKE so that the anchor bolt is as-low-as even with the lower edge of the theoretical "brake bridge" (B-stay yoke) BECAUSE more than an inch of mud-and-crud would probably mean that your wheels would probably be too heavy to turn (for me, at least!) and/or the crud would be jammed up around the BB & make pedaling close to impossible.