Let's talk about brakes

[dogman dan]

One bike that makes a good starting point is a mongoose blackcomb. The frames geometry makes the most of a cheap shock, which can be upgraded. You can buy them at walmart by ordering it online. disk brakes.

A heavy pig of a bike you'd need a ski lift helping you to like riding it. But add a motor and it gets pretty nice. Strong frame, and steel dropouts in the rear. It doesn't have a triangle, but the frame is easy to bolt boxes to. I think there's one up for sale now in the used section.

 

[spinningmagnets]

Side-pull calipers are the cheapest and the worst. I am comfortable with the amount of relative safety I get from V-brakes in the back. Concerning front disc vs rim in the wet and snow...

If you are riding through wet/snow (forced to, as a result of parked and moving cars) your tire is picking up slush on every turn, so no matter how well the rim-brakes are cutting through the slush/wet to rub against the rim, every revolution picks up more slush.

A disc 'may' slip some on the first slushy revolution, though it 'should be' cleaner from the start, compared to a wet rim which lives close to the road. But by the second time around, the disc is relatively clean and dry.

Always ride with two well-adjusted and working brakes, and I highly recommend a front disc under all circumstances. In the wet, not only will your brakes work 'less',...the cars around you will lock up and slide over you if you don't stop in time.

 

[JennyB]

I have also seen some rims that have grooves in the braking surface, presumably intended to channel water away from the braking surface itself. The 9C's rim I have has one thin groove like that; I don't know how effective it might be (only had a couple rainy days that I tested it in, and mostly used the regen braking to slow down).

That groove's not intended to shed water. It's a telltale to let you know when your rims are worn out (something you don't have to worry about with discs :lol.

 

[biohazardman]

This topic comes up from time to time as it should. Brakes are very important and as we usually go faster for longer lengths of time with a heavier bike we need to make sure we can stop regardless of the road conditions. My first e-bike a 65lb hard tail had the cantilever rim brakes. To be perfectly honest I never had a problem with them. I kept the rims and pads clean and they always stopped me, from the lower 20mph mark, even in the rain and a few times in the snow for short distances. I went with a full suspension unit and watched the weight on the next build and wound up with a plush riding 55lb bike. Still my speed was up considerably, sometimes near 35mph, so upgraded the mechanical disks to 8 inch. What a difference from the rim brakes! So much better I have been up on the front wheel before while braking hard, to dodge a van who cut me off, don't think the rim brakes would have done so. Disks are better and oversized rotors are a definite step up also. I have hydraulics but have never seen a good reason to put them on as yet although with more weight it might be a good idea. I will not likely build another bike without the set up I now have. It's very easy to put a reed switch on the mechanical disk at the rear for motor cut off when you brake also. Get the best you can afford as your life literally depends on it.

 

[chrisvw]

I agree with the general consensus that disc brakes are generally better. I'm not sure I'd agree that hydraulics are necessarily any better than mechanical disc brakes. My tandem has mechanical (so it can be disassembled) 8" discs and I don't have the least hesitation to go down even serious hills (I live in Colorado where a serious hill can be hundreds of feet of descent).

My ebike has v brakes. They are barely adequate as they are cheap brakes. I've had the metal release bracket on the top fail on both the front and rear. Unfortunately, I haven't found a sturdy, long reach V brake that I need to reach around my fenders.

If you do both rain and hills you should also be aware that rim pads can wear really quickly. It is literally possible to wear through a set of pads in a day. The crap that carries up into your pads from the road in the rain will abrade the pads in no time. In the "triple bypass" bike ride two years ago, a number of the riders had to stop when their pads wore "metal to metal". (Again, long descents)

All that said, with regular maintenance, you should be able to use either rim or disc brakes

 

[kriskros]

Kool Stop dual compound mountain brake pads.... to qote Sheldon Brown " these are the best brake shoes you can buy at asny price" i use these on my Norco mtb with a bafang motor and a ping 36 12amp bat....not the power that many of you use,but THESE SHOES STOP me fast and hard....set in V brakes

 

[LI-ghtcycle]

I agree with the general consensus that disc brakes are generally better. I'm not sure I'd agree that hydraulics are necessarily any better than mechanical disc brakes. My tandem has mechanical (so it can be disassembled) 8" discs and I don't have the least hesitation to go down even serious hills (I live in Colorado where a serious hill can be hundreds of feet of descent).

My ebike has v brakes. They are barely adequate as they are cheap brakes. I've had the metal release bracket on the top fail on both the front and rear. Unfortunately, I haven't found a sturdy, long reach V brake that I need to reach around my fenders.

If you do both rain and hills you should also be aware that rim pads can wear really quickly. It is literally possible to wear through a set of pads in a day. The crap that carries up into your pads from the road in the rain will abrade the pads in no time. In the "triple bypass" bike ride two years ago, a number of the riders had to stop when their pads wore "metal to metal". (Again, long descents)

All that said, with regular maintenance, you should be able to use either rim or disc brakes

You know, the real problem is slowing down on those descents! They just need to tuck and go! :lol: jk he he

I'm sure that you're right on pad wear, but again, I really believe it goes to your design of E-Bike also, when your forced to go big, as with most any hub motor kit, then you have to go big with the frame, the brakes, the battery, etc. , etc.

If you stay light, as in a RC friction drive, anything that was good enough for the bike when it was non-motorized will be good enough with just a scant 5 - 10 lbs added to the weight.

Here again, it all really depends on how, where and how fast you ride (off road needs disc if your getting muddy, I'm mainly talking street riding). I just wonder why if discs would be so needed even on heavy bike, why then are bikes such as the Surly Long Haul Trucker still using rim brakes? So I think it's really about speed and how you ride.

I agree once you hit that mark of high weight (especially un-sprung weight) not sure where the line is .. maybe 80lbs? THEN you DO need to upgrade brakes, frame, etc. But as long as you stay on the lighter side, I think any good quality brake will serve you well.

 

[Ykick]

I suggest you qualify the speed of this rig before ruling either type of brake system in/out.
Maintain things around the 20-25 MPH, properly installed/adjusted rim brakes with quality pads (koolstop) work quite well for me in all types of weather. Increase average speed up to around 30 MPH or more and requirements will change exponentially. That is, double speed seems to require 4-6 times more braking capacity.

It's the same deal over and over as I see with this hobby/pusuit. Keep the electric assist close to the performance a very swift athletically propelled bicycle - quality bicycle stuff seems to work okay. However, introduce the need for speed and you might as well start out building it as a high-speed motorcycle with pedals. Practically need DOT rims, suspension, brakes, tires, lighting, etc.

It's a balance to keep it "bicycle" yet give yourself useful assistance from the batteries without turning into a DOT ride.

There can be horrors from practically any type of mechanism. I've seen rim pads turn/twist in the mounting hardware and dig into the tire side wall when used hard at excessive speeds. Hydro hoses can pop, cables can fail - it all comes back to DEFENSIVE operation of these things at every opportunity. In the motorcycle world they don't call 'em "donor cycles" for nothing...

 

[Hillhater]

An interesting point from wiki re disc brakes..

Since about 2003, riders have reported a dangerous problem using disc brakes: under hard braking, the front wheel comes out from the dropouts. The problem occurs where the brake pads and dropouts are aligned so the brake reaction force tends to eject the wheel from the dropout. Under repeated hard braking, the axle moves in the dropout in a way that unscrews the quick release.

There are some other points on Wiki comparing the different types of brakes... ( ever wondered why the "money no object" pro road racers use caliper brakes ?) .... such as the way disc brake installation compromises the strength of the wheel/hub configuration.

 

[Drunkskunk]

( ever wondered why the "money no object" pro road racers use caliper brakes ?) ....

Actualy Road Race bikes don't use them for several reasons unrelated to brake preformance. Disk add rotating mass to the wheel. on a "money no object" ultra lite race bike, the centerfugal force of the disk is a handicap for a rider trying to accellerate. The Caliper brakes are also more aero than the disk. they are built not to extend past the fork and don't add any frontal area to the bike. and since the area where the top of the wheel pass through the fork is an area of turbulance already, the brake doesn't add turbulance to the airflow. The Wheel is also stronger when the spokes don't have to be offset, so fewer spokes and/or thinner spokes can be used and the wheel can be lighter.

 

[Hillhater]

Actualy Road Race bikes don't use them for several reasons unrelated to brake preformance. ...
.. The Wheel is also stronger when the spokes don't have to be offset, so fewer spokes and/or thinner spokes can be used and the wheel can be lighter.

+ the spokes dont have to take the braking forces either.

And obviously they are satisfied with the rim brakes ability to work effectively on those long fast downhill runs from the mountains.

 

[JennyB]

Actualy Road Race bikes don't use them for several reasons unrelated to brake preformance. ...
.. The Wheel is also stronger when the spokes don't have to be offset, so fewer spokes and/or thinner spokes can be used and the wheel can be lighter.

+ the spokes dont have to take the braking forces either.

And obviously they are satisfied with the rim brakes ability to work effectively on those long fast downhill runs from the mountains.

As Nuvolari said: "Brakes are no good. They only make you go slower."

I'm pretty sure discs are banned in road racing. Imagine the effect on the peleton in the wet if only the guys in front have discs!

 

[Hillhater]

You dont need (or want) very much brake power on a road race bike in the wet !

 

[AussieJester]

Actualy Road Race bikes don't use them for several reasons unrelated to brake preformance. ...
.. The Wheel is also stronger when the spokes don't have to be offset, so fewer spokes and/or thinner spokes can be used and the wheel can be lighter.

+ the spokes dont have to take the braking forces either.

And obviously they are satisfied with the rim brakes ability to work effectively on those long fast downhill runs from the mountains.

As Nuvolari said: "Brakes are no good. They only make you go slower."

I'm pretty sure discs are banned in road racing. Imagine the effect on the peleton in the wet if only the guys in front have discs!

Width of tires combined with the high pressure these lycras run i doubt disk would make one iota of difference over caliper brakes even, wouldnt take alot to lock them up.

IMHO, if you have an e-bike thats capable of over 50km/hr you should prolly be using disks, with the increased weight due to battery and motor disk brake setup to me, is an easy and the only choice... Having used cable and hydraulic bicycle calipers on disks gotta say hydraulics absolutely pwned the cable setups.

KiM

 

[icecube57]

I personally use vbrake front and back. My rear v brake is useless. Ive trued my rim 3 times and its tension pretty high. A big bump or several hundred miles I start having a wobble. So I can get my pads as close as I want to. So in regular riding it feels slightly soft. I normally use them to slow down. But in an emergency it will lock the tire. My front v brakes work very well. If I need to stop I use the front. Very firm grip on the lever. It feels solid.I keep the pads clean . My riding habit is plan your braking. If im coming to a red light or stop sign I regen all the way there and then I apply my v brakes when the speed drops below 10 mph. I know in emeregency situation this isnt going to work but Ive gotten my bike to stop on a dime from full speed with in a car length or two. I would love disc for longevity of pads and braking endurance. But its going to set me back atleas 150 for a new rim rotor and brake.

 

[blueb0ttle2]

I'm thinking of making my ebike safer to drive on wet roads by replacing the front rim brake with a drum brake like this one...

I only go at about 15 MPH, and I don't feel the need to invest the time and money for a disc brake at that speed.
Any thoughts/caveats? The drum brake is only about $60-70 USD

 

[Ben_S]

I ride in the rain all the time, I don't know where this idea that rim brakes fail in the rain comes from, I guess it depends on the quality of your rim brakes, and there are definitely better quality ones on what you typically find in a bike shop verses dept. store. I have seen a ton of used bikes, and never one had rims warn out from the brakes? I wonder how many of you have actually seen that happen? I'd be curious to see it, not saying it doesn't happen, but I have to say I am skeptical.
...

LI-ghtcycle:
I live on the west coast, and have been biking (non-electric) for many years, just recently turned electric. My first mountain bike had Magura Hydraulic Rim brakes. Pretty much the best rim brakes you could get at the time. Not cheap either, good quality stuff. At my peak, I road this bike probably 5000 km a year as my primary commuting bike. While these brakes had excellent modulation, I could lock both wheel of the bike on command in dry weather when new. I'd kill a set of pads about every 3 months (Yes fast/agressive riding, but no electric, just me). In doing so it would also cake up the rims with residue from braking. At that point in the rain the brakes would become entirely ineffective and squeally! It was crucial to remove the rim and clean it thoroughly with some heavy duty stuff. Needless to say after a couple years, the rim would wear right through. Although I generally caught it with regular maintenance, I can vouch for the rim wearing through and loss of performance in the wet. And that was without the extra weight/momentum of going electric.

My wife's bike is an "off-the-shelf" giant road bike. Cantilever rim brakes. Wore through the rims in about 6 years of occasional riding and probably 6 sets of pads. Braking performance wasn't great. Although the components probably aren't amazing either. But it gives you something to contrast my high performance setup above. Same conclusion though: low performance when wet and increasinly low performance over time with eventual destruction of the rims. She's also NOT an agressive rider like me - very average city commuter.

My next bike is a rocky mountain RC30 with disc brakes. Average Shimano mechanical discs, nothing too fancy - "midrange". Definately a huge step up in wet weather. Now that I've turned it electric I'm seriously considering hydraulic discs. I like to go fast (with or without electric!) and like the control of good brakes. While every system has its pros/cons, hydraulic disc definately holds the top position for pure stopping power. Many of the hydraulic brake manufacturers are now offering warranties on their systems for up to 5 years, so I think lots of the unreliability in discs was due to early development products and has since been worked out.

To compensate for the possible added stress in the spokes/rim, I'm simply going to use a nice double eyeleted (ferruled) downhill rim with some nice heavy gauge (13g) spokes, of course 36 spoke. We'll see how well it survives in a few years, but I think the mechanical/performance related weaknesses of discs can be easily overcome, while the mechanical/performance related weaknesses with rim brakes are pretty much intrinsic. So in the end its really just a matter of budget more than mechanical pros/cons.

- Ben

 

[blueb0ttle2]

I'm having a Sturmey Archer Drum Brake installed on my Currie Ezip's front tire, and will comment on its performance as soon as I get it back from the shop. I thought it would be a good low maintenance alternative to rim brakes or disc brakes. I don't travel very fast, so you speed demons out there will probably not benefit from my tests

 

[beast775]

i like sa drum brakes,i had one a few years ago,wish i never sold it .

 

[Hillhater]

I'm thinking of making my ebike safer to drive on wet roads by replacing the front rim brake with a drum brake like this one...

I only go at about 15 MPH, and I don't feel the need to invest the time and money for a disc brake at that speed.
Any thoughts/caveats? The drum brake is only about $60-70 USD

What rim brake do you have ?
A "V" brake (not caliper or cantilever) with correct pads will out perform that drum brake and lock the wheel , wet or dry.
Every other vehicle in the world has progressed from drum brakes to some form of disc ( rim brakes are in effect disc brakes).
Discs are not expensive, you can buy a set (2) of disc brakes for $20 new
http://cgi.ebay.com.au/Hollow-out-Bike-Bicycle-Disc-brake-160mm-/280577753168?pt=AU_Sport_Cycling_Parts&hash=item4153bcc050
but then you will need a disc hub too for another $20.

 

[Ykick]

I rode a Japanese market bike for a couple years, common to see rear drum brakes. It was fine, but didn't experience any clear advantage to it over good rim brakes except perhaps less delay during rain/wet soak conditions?

I used to be a disc snob but over the years I've come to accept and use decent rim brakes. They're sorta perimeter disc brakes anyway.

Good pads and adjustment(s) 'can lock either front/rear wheel. What more do you need from brakes? Of course, speedsters in the +30MPH group will see very rapid wear so disc may hold advantage for that style of riding.

 

[GTR2EBIKE]

A "V" brake (not caliper or cantilever) with correct pads will out perform that drum brake and lock the wheel , wet or dry.

I'd really like to see a video of you locking up a front wheel with a "V" brake in the dry.

 

[Beavinator]

Since disc brakes have become so common the price has dropped so much that there is really no choice anymore. For the amazing stopping power you can get out of a disc its the only way to go in my opinion. I just bought a set of 4 piston caliper discs for 150ea and they are unreal!

 

[blueb0ttle2]

I'm considering drum brakes since I wouldn't need to adapt an old V-brake fork to work with disc brakes. I think that disc brakes probably are the best, but given my resources I think it best to experiment with something low maintenance, since I am a regular commuter and not an extreme cyclist. After all, I'll never travel faster than 20 MPH. I'm interested in building something sturdy and utilitarian.
Different bikes for different blokes :lol:

 

[Rifle]

I rode a Japanese market bike for a couple years, common to see rear drum brakes. It was fine, but didn't experience any clear advantage to it over good rim brakes except perhaps less delay during rain/wet soak conditions?

I THINK A REAR DRUM BRAKE MAKES A LOT OF SENSE. YOU'RE NEVER GOING TO HAVE MUCH STOPPING POWER BACK THERE COMPARED TO THE FRONT, SO MIGHT AS WELL DO THE LOWEST MAINTENANCE OPTION. (IT'S CAPS LOCK DAY)