Bicycle Mechanics - Decrease stopping distance

I've tried almost everything I can think of.
I've brought the shoes right in till they are practically touching the rim, lubed up everything, all the springs etc.
But my bike still has a massive stopping distance, I'm thinking I should try new shoes.

How big a difference is a good pair of brake shoes as opposed to a bad pair?
I've felt my shoes with my fingers and they feel awfully smooth and 'dry'.

Thanks in advance.

Buy some Kool Stop Salmons.

I'm not much for rim brakes, but after seeing them recommended so highly on this forum, I tried some and they do make a remarkable difference.

New good pads are a night and day difference. Go for it.

What kind of bike? What style of brake? Are the rims chromed steel or aluminum?

jim

Even with the Kool Stop Salmon's "toe" for "cleaning off the rim", which requires you to set the shoes a bit further away from the rim than I like, they break a lot better than the Shimano DuraAce pads that I had on the bike (they were there when I got it second hand).

Go try it. It makes a difference.

I've tried almost everything I can think of.
I've brought the shoes right in till they are practically touching the rim, lubed up everything, all the springs etc.
But my bike still has a massive stopping distance, I'm thinking I should try new shoes.

How big a difference is a good pair of brake shoes as opposed to a bad pair?
I've felt my shoes with my fingers and they feel awfully smooth and 'dry'.

Thanks in advance.DON'T set the pads close to the rims. Your hands have the most strength and control when they're closed. You should set the levers so they lock up the tyres just before the levers touch the bars.

And you are using the front-brakes righit?

DON'T set the pads close to the rims. Your hands have the most strength and control when they're closed. You should set the levers so they lock up the tyres just before the levers touch the bars.

DO set the pads as close as possible to the rims, for quick responce time and maximum gripping power.
If your hands are too small to get a good grip on the levers, then you can adjust those via the screw on the levers themselves and the barrel adjuster.




Are you using the correct type of brake lever for your type of brakes?
Some have different amounts of travel vs force.

there's no adjuster to set reach on road style aero levers. you have to use a shim or get levers specifically designed with shorter reach in mind.

there's long pull, which is for V-brakes and then there's short pull, which is for road calipers, cantilevers, etc. and they shouldn't be mixed.

don't forget to toe-in the pads and wipe down the rim with some alcohol.

What kind of brakes do you have, caliper, vee or cantilever?

don't forget to toe-in the pads and wipe down the rim with some alcohol.

He means use alcohol to wipe the rims down, not use alcohol while wiping the rims down. :D

:lol:
you could try both at the same time :innocent:

I'm with Danno with the front pads and xeno for the back pads. For me, that means more modulation up front since I primarily use my front brakes.

Rear brakes are for shedding speed in turns or just to augment to fronts so they don't get much use. Well, I also use them when I am out of saddle and some ped cuts in front of me and the front would lead to an endo, with the added bonus that the rear skidding will make said ped hop out of the way.

Make sure the shoes make full contact with the rim. Forget toe-in unless you hear squealing.

new pads +1

Alternatively, if you can brake hard enough to lock up the wheels or risk doing an endo' then you'll need tires with more grip.

? Are the rims chromed steel or aluminum?
jim
Until the OP answers this question, none of our suggestions mean anything. If the answer is "steel" we can stop suggesting brake refinements right now.

If not steel rims get the shimano Durace pads. Bicycle Science has tests that show them the most effective in the wet as well as dry.

Until the OP answers this question, none of our suggestions mean anything. If the answer is "steel" we can stop suggesting brake refinements right now.

Agreed as well as some of the other questions. What type, make, model, etc.

Different pads are not the answer to all braking problems.

New pads and don't under estimate the value of some good calipers. My road bike came with some rebranded Cane Creeks. I just thought crappy stopping was part of the roadie experience. I got a good deal on some Ultegra calipers and now I can stop just as quickly as I could on the commuter.

I'm with Danno with the front pads and xeno for the back pads. For me, that means more modulation up front since I primarily use my front brakes.

Rear brakes are for shedding speed in turns or just to augment to fronts so they don't get much use. Well, I also use them when I am out of saddle and some ped cuts in front of me and the front would lead to an endo, with the added bonus that the rear skidding will make said ped hop out of the way.

You shouldn't use the rear to 'augment' the front brakes. If you're already braking hard on the front one your weight is shifted forward so activating the rear brake is possible to cause the rear wheel to lock and slip out from under you.

No answer back from the OP. I think he endo'd and is in hospital...

The OP said he lubed everything. I hope he didn't put lube the rim!

Without more information, like the type of brake, none of us can help too much more. There is also the brake phenomena when going to a road bike from an MTB, which riders complain of poor brakes, but don't understand that a road bike is faster and has less rolling resistance.

Stopping a road bike with 23mm wide tires at 25mph will take longer then an MTB with 2" wide tires at 12mph.

Alternatively, if you can brake hard enough to lock up the wheels or risk doing an endo' then you'll need tires with more grip.

I disagree. I don't believe different tires offer different braking abilities.

I disagree. I don't believe different tires offer different braking abilities.
That's right. Unless the tires are very slick, the limit to a bicycle's stopping power is the point that the rear wheel is totally unloaded. That happens on a typical road bike at just about 0.5G and any decent tire will maintain traction to well beyond that point.

I started with cheap nasty-ass V-brakes, first changed the pads, then changed the brakes themselves with good V-brakes.

Both made a difference, but the pads alone were good enough to create the risk of endoing that wasn't there before.

You shouldn't use the rear to 'augment' the front brakes. If you're already braking hard on the front one your weight is shifted forward so activating the rear brake is possible to cause the rear wheel to lock and slip out from under you.

Never had that problem. When I have to brake that hard, I usually redistribute my weight, as in my but is way behind the saddle, so they both work fine.

If you haven't had that problem it means you aren't using your front brake to its full stopping power potential. You want to squeeze down on the front so hard that the rear wheel is just about to come off the ground (like almost about to do a controlled endo), that will slow you down faster than any amount of 'help' from the rear brake will.

Why do V brakes work so well?

Why do V brakes work so well?

They've got a fair degree of mechanical simplicity and lack any particularly bad failure modes. Plus, you can fit them nicely around large tires. I suspect the mountain bike fork, being a fairly sturdy thing, probably helps keep the whole system rigid.

On the other hand, I also suspect that it's all about monkeying with mechanical advantage and brake pads. Change the mechanical advantage of the brakes and the levers and you can make the brake feel more powerful without actually making it better. Put decent pads on and even crap brakes suddenly have power.

Why do V brakes work so well?

High mechanical advantage.

V-brakes apply the same maximum braking-force with less finger-pressure. But they won't stop you in any shorter distances than good caiiper-brakes.

Control and modulation is a hard-to-measure factor in braking systems. When you've got your belly on the seat with your butt inches off the rear-tyre, you're actually lowering the COG and moving it back. This lets you build up higher deceleration forces by the time the rear-wheel is unloaded. This is when maximum deceleration force is pushing back on the front-wheel. Trying to stop faster than this will just cause the rear-wheel to lift higher and flip you over.

However, the ability to hold the bike at that delicate balance with the rear-tyre chirping off the tarmac is difficult. Requires top-notch equipment and lots of practice:

http://i42.photobucket.com/albums/e346/DannoXYZ/Motorcycles/ElenaMyers2.jpg

BTW - motorcycles have the advantage of lower COG, longer wheelbase, stickier tyres and much, much larger contact patch. Cars are even better at braking and if you mess up, it's no big deal.

However, the ability to hold the bike at that delicate balance with the rear-tyre chirping off the tarmac is difficult. Requires top-notch equipment and lots of practice:


It is a good skill to practice. I do it all the time on commutes at stop signs and red lights. Freaks people out since I am still going very fast and it doesn't look like I am stopping. Had cops yell at me before, telling me to stop fooling around.

Much harder on my road bike.

I can't believe this thread is still going on and the OP has NEVER responded as to what rims he has. We are talking to ourselves at this point.:)

Long stopping distances relative to what? Your previous bike? How this bike used to perform? Did you gain 50 pounds?
http://www.sheldonbrown.com/brakturn.html

I disagree. I don't believe different tires offer different braking abilities.

Which is mostly correct. The front tire has greater braking potential because as you slow down your weight shifts forwards, even if you don't move. However, for any given rate of deceleration, your front wheel will have the exact same results as braking your rear wheel, at least as far as an endo is concerned.

DannoXYZ, I want to see a picture of that motorcyclist one second after this one was taken!

I can't believe this thread is still going on and the OP has NEVER responded as to what rims he has. We are talking to ourselves at this point.:)

Someone (Danno?) mentioned he/she may have had an accident on account of brake failure - let us hope that is not the case.