Front vs rear brakes
 

I have a follow-up question about my Raleigh Sports brakes. A local bike guy who specializes in 3-speeds helped me fix the rear brake and swap out the old odd for some newer ones, but when I went for a ride today, I noticed that the rear brake did NOTHING to actually stop the bike. It may have slowed down a bit but it certainly didn't "brake" the bike. The front brake worked fine. I co press and the bike stops, but when I compared and used the rear brake alone, it was inept. I typically use them together, applying more pressure to the front brake than the rear, having read that's the way to do it, but I'm curious if my rear brake is actually functioning properly, given of ineffective it is at braking by itself.

Thanks all!

I would not be satisfied with a rear brake which could not lock up the wheel with reasonable lever pressure. I would go back to the person who did the work and have it made right. It is possible that the rim and pads could be contaminated with oil from the hub or chain or there could be any number of other reasons for the issue.

Stand next to bike. Roll bike backwards while pressing the rear brake. Bike should stop. If it doesn't; check brakes. Are the pads lined up correctly? Not too old? Etc.

You should find someone at a good local bike shop with the skills to work on those brakes. The first person does not appear to have those skills.

Not yet mentioned is the actual situation at hand, blaming people doesn't change the situation.

The bike has many of the worst cases for effective brakes. Chrome steel rims which have less friction for the pads to work with. Long reach caliper arms reducing the leverage. Not known but a likely assumption is that the replaced calipers are also more flexible then the steel calipers that were original. Also that the pads are likely old and/or low grade. Then there's the cables. If the OE ones they have a fair amount of friction, not being of lined casings or redrawn inners. Last are the levers with limited travel.

Combine all these factors and it's no wonder to any one who works with bikes that the brake effectiveness sucks. Any mere mechanical adjustments only make what is poor abilities still fail the too high expectations. Andy.

Rear brakes can also be a hassle with long cable housing and old cables.

If not gripping or releasing properly, expect new cable housing and cables in your near future.

Are the wheels reasonably true? If not, then maybe true the wheels + adjust the brakes. If the wheels are true, then how close are the pads to the rim? 1/8" or so is a good distance.

Thank you for the feedback, everyone. The pads are new, and the wheel is true. The calipers, levers, and brake line all seem fine as the pads firmly grip the wheel. It's just that wheel keeps rotating through as I ride. I'll check for Hun oil--I hadn't thought it could be there. I wiped excess off the side of the wheels but I don't think the top.

Chain oil can easily contaminate your rear braking system. Perhaps time is the best way to get rid of it. Alcohol?

How much do your brake levers move? If they're bottoming out before stopping the bike, then you need levers with more pull or callipers with less pull, or an entire system with less flex, or tighter adjustment to the brake callipers.

I think some of the more modern levers such as the Origin8 Classique, TRP RRL have a moderate amount of pull. The Tektro R340 may be similar. The Tektro R520 levers have a LOT of pull.

Do you understand the most basic of Physics? :rolleyes:

when decelerating , the mass is weighting the front , shifted from the rear.

that is largely Why your front brakes are more effective.. ever seen a Stoppie?

still have the steel rims?

Thinking that the rear brake should always be able to lock up the rear wheel does not take into account an upright bike like the Raleigh Sport 3 speed with steel rims and flexy brake calipers. Even with aluminum rims I'm not sure it's reasonable on an upright bike to expect to be able to lock the wheel.

When I was kid I had an upright Schwinn 3 speed with chrome wheels and there wasn't any problem getting the brakes to lock up the rear wheel and skid on the pavement...as long as the wheels weren't wet!

Without seeing the bike and test riding it I wouldn't be able to specifically say whats going on other than to guess like others are doing. You could try some brake cleaner fluid on a cloth and wipe down the sidewalls of the wheels.

However, as a word of advice and caution, you need to get rid of those steel wheels, there's a reason they were banned from being sold on bikes because they were dangerous and kids got hurt and killed on bikes with those wheels. If you haven't already experienced this you will, but even just a little bit of water on the rims would take you 10 as long of a distance to stop as you would if the wheels were dry, add rain instead of just a little water and you've got a disaster waiting to happen. So buy yourself a set of cheap aluminum wheels ASAP!

Is not expected that an upright bike would allow a rear wheel to lock up?

Also, I can't remember who asked, but if I push the bike backwards, the wheel does a better job at locking up.

There was some oil on the rim, which I cleaned with a towel.

First off a towel alone isn't good enough, it may appear like it's clean but it's not, you need to use some solvent on a rag and wipe the rim down being careful not to get any on the tire which if I were you I would remove the tire and clean the rim.

An upright bike can lock up the rear wheel if the brakes are good...and the wheel doesn't have oil on it!

It sounds like you have coaster brakes when you say you pedal backwards and the rear wheel locks up. Coaster brakes actually work quite well if adjusted correctly. However if you have coaster brakes on the rear, they never put those on the front, then you shouldn't have caliper style brakes on the rear which if you don't have caliper brakes on the rear than the oil on the rim would have no effect on braking. There is also a possibility you may have both, coaster and caliper on the rear.

So IF you have coaster brakes, which it appears you probably do, then the coaster brake may not be adjusted correctly, so instead of me typing endlessly on how to do that the internet came to my, and yours, rescue; please read: Bicycle Coaster Brakes

Thanks--definitely no coaster brakes. What kind of solution should I use for the rims--baby powder to absorb the oil?

Why would the bike stop if you pedal backwards?

Ok then. Just use solvent, baby powder won't do anything. Brake cleaning fluid works, Acetone, paint thinner, certain cleaners like Purple Power, Simple Green, etc, works but you have to rinse with water when done with those types of cleaners, as a last ditch effort if you don't have anything in your garage gasoline will work; just don't be smoking anything when cleaning with gasoline, Acetone or paint thinner! I would take the tire off first before you clean.

I forgot, you need to clean the brake pads too with the same stuff you use on the rims before you use them on the clean rim.

He never said pedal backwards.

I've recently learned that old bikes had HARDER brake pads that went with the steel rims. It's possible that you replaced the pads with softer pads thinking they'd brake better, but in reality that's opposite of what happens. Pads today are softer to avoid prematurely wearing aluminum brake tracks.

I've not had good luck with steel rims and decent braking performance unfortunately. My default response to people asking about it is "In most cases you can't expect the same level of braking with steel rims as you can with aluminum rims." Of course, that's a bit of a white lie. Given enough adjustment and time to play with it, you can get steel rim brakes working alright. I usually just tell people to buy a set of $10-15 rims from our shop and be happy in many ways. Many things in the biking world are sold as "upgrades" when in reality the performance benefit is marginal. An aluminum rim was not one of those things.

I wonder if anyone has ever tried v brakes on steel rims.

I assumed when he said he pushes the bike backwards he meant pedals backwards because some people may use that wording to describe that, and it made sense that's what he meant, obviously I was wrong in that assumption.

I think he was referring to counter balancing the weight forward from inertia, to help you have a balanced braking effect, rather than a rear wheel too light and sliding around, which alone could cause you to crash.

I say this to many of my roadie friends, try mtb riding and learn some basic skills you thought you already had. They almost always come back a bit humbled but better from the experience.

I misunderstood the poster's question. When I meant to communicate is that when I spin my wheel backwards--as if moving in reverse--the rear wheel stops more quickly than when moving forward. The brake pads, though new, were developed for old steel rims. They have a leather strip in the middle that helps with braking. It's certainly not the pads. The front pads stop the front wheel. How can I tell if there's an issue with my rear brake cable?