Rim Vs Disc Brakes

[Sad Clouds]

I notice a lot of riders go for rim brakes, especially on the rear wheel. Some of those people tend to say rim brakes are better, because they are not affect by the flex in the spokes. Personally I think disc brakes are far superior, given a properly built wheel. Take a strong rear hub, decent rims and get a professional wheel builder to lace it 4-cross. I'm pretty sure there won't be much flex in the spokes. Also I don't think disc brakes are that much heavier and they give you consistent and sharp performance, no matter the weather.

What do you guys think?

[Dwarf Shortage]

I think your username is hilariously depressing

Also, that either my past experience of disc brakes has been shoddy, or that disc brakes just aren't for me.

To me they just feel, bleurgh. Like they take a relaxed approach to braking, and just chill around all "Oh a car's appeared in front of you? S'pose I better start slowin' you down pretty soon then, eh?" whereas rim brakes are just like "POWEERRRRRRRRR", I've never used trials-specific disc brakes though.

The best thing about discs for me is the modulation, especially when someone uses it to nose manual over a woman, I loved that video. (I'll post a link when I'm not on my iPod).

A few people on here love their vees, some love their Maggies or those Echo ones, and others love their discs, it's just personal preference, looking at the pros and cons for each, then deciding which suits you best.

Have a vote as well, this spate of new members that can actually spell pleases me.

Well done Sire

[Sad Clouds]

Also, that either my past experience of disc brakes has been shoddy, or that disc brakes just aren't for me.

Oh, sorry to hear it. There are many disc brakes out there, some are good, some are not. From my experience disc brakes are a bit fiddly to set up, i.e. you need to bleed them properly, make sure there is no air in the lines. Also you need to make sure you're using sintered and not organic brake pads, organics are really for XC riding only.

I've never used hydraulic rim brakes, which is why I'm asking here. I've seen many riders use them, so maybe I've missed something out. I've used regular V-brakes and when it rains and oil from the chain gets on the rim, you may as well start braking with your feet.

I have used Formula The One disc brakes, with Goodridge steel braided hoses. I've ridden in the rain and snow and they work flawlessly.

[Ali C]

discs are powerful enough, if I rode mod I would have rear disc no question.

On a stock though, no matter what spokes and pattern you use, it will be more vague than stopping the wheel on the rim. another factor is hitting the rotor when missing a move (like a sidehop) and trashing it.

Personally I am a huge fan of vee brakes, you mention water and oil making the performance weak, well Hydraulic rim brakes have the same issues, that"s why you grind the rims, to give the most braking power in all conditions. Combine a grind with some good pads, then the brake power is amazing. The same can be done for vee brakes, plus vees actually have a higher mechanical power so can work better than a hydraulic system and they have a lot more advantages too.

[modifier]

I have to admit that I haven't used non disc brakes for a long time, except on some of my old bikes that almost never get ridden, but before discs came around I of course tried everything to get the best braking I could short of textured rims that some trials riders use. My many years of experience have showed me that rim brakes will stop you but not very well compared to modern hydraulic disc brakes. My newest bike has the 2011 Shimano Saint brakes and they are amazing both in power and modulation. I run a 203 in the front and a 180 in the rear.

There was another thread where someone was asking for a recommendation for dis brakes and almost everyone said that they thought the Avid BB7 brakes were the best by far. Well perhaps this is why people don't like disc brakes. Once again these brakes work but not nearly as well as any hydraulic brake I have every run, even the first generation Hays brakes were better. I think everyone is afraid of brake fluid because they never work on their cars anymore. It's the same thing, just a little more touchy. Yeah it can be a bit of a pain to get them properly bled the first time but usually once they are set up that is it. You can ride for years without having to do anything other than switch out pads, which is a lot easier and less frequent than switching out rim brake pads. If they say less maintenance is their argument I say sorry but rim brakes take far more maintenance than any discs I have ever run. Plus there is the whole rim has to be true and not bent and dry thing for rim brakes to work well. These things have no effect on discs.

As far as spoke flex... I think that is like the rigid frame mountain bikers harping on about how they are loosing so much energy with their frame flexing 2mm while climbing. Sounds good. But I don't think so. They are just buying into some vague notion of how things work from hearsay that doesn't have much to do with real world results. If the wheel is built right it won't flex much. The tire will likely flex a lot more. Do you think riding solid rubber tires would help you get through sections? Same difference. Plus even it it does flex a bit it's not going to effect your riding. It might give you a little spring to launch better or a little cushion on a landing. If the wheel is built poorly or has loose or missing spokes it will flex more of course.

If rim brakes were better motorcycle trials riders would demand manufacturers engineer rim brakes for their motorcycles. I haven't seen any of that.

The one argument for rim brakes I can see is on 20" wheel bikes where their axles are low to the ground so disc brakes might get damaged. Also rim brakes and mechanical discs are cheaper so if money is an issue then better to ride mechanical than not ride.

In the end I'm sure modern rim brakes work fine and if that is what you like run them. I'm just saying they don't work better and aren't easier to maintain.

Edited November 5, 2010 by modifier

[Ali C]

I have to admit that I haven't used non disc brakes for a long time, except on some of my old bikes that almost never get ridden, but before discs came around I of course tried everything to get the best braking I could short of textured rims that some trials riders use. My many years of experience have showed me that rim brakes will stop you but not very well compared to modern hydraulic disc brakes. My newest bike has the 2011 Shimano Saint brakes and they are amazing both in power and modulation. I run a 203 in the front and a 180 in the rear.

There was another thread where someone was asking for a recommendation for dis brakes and almost everyone said that they thought the Avid BB7 brakes were the best by far. Well perhaps this is why people don't like disc brakes. Once again these brakes work but not nearly as well as any hydraulic brake I have every run, even the first generation Hays brakes were better. I think everyone is afraid of brake fluid because they never work on their cars anymore. It's the same thing, just a little more touchy. Yeah it can be a bit of a pain to get them properly bled the first time but usually once they are set up that is it. You can ride for years without having to do anything other than switch out pads, which is a lot easier and less frequent than switching out rim brake pads. If they say less maintenance is their argument I say sorry but rim brakes take far more maintenance than any discs I have ever run. Plus there is the whole rim has to be true and not bent and dry thing for rim brakes to work well. These things have no effect on discs.

As far as spoke flex... I think that is like the rigid frame mountain bikers harping on about how they are loosing so much energy with their frame flexing 2mm while climbing. Sounds good. But I don't think so. They are just buying into some vague notion of how things work from hearsay that doesn't have much to do with real world results. If the wheel is built right it won't flex much. The tire will likely flex a lot more. Do you think riding solid rubber tires would help you get through sections? Same difference. Plus even it it does flex a bit it's not going to effect your riding. It might give you a little spring to launch better or a little cushion on a landing. If the wheel is built poorly or has loose or missing spokes it will flex more of course.

If rim brakes were better motorcycle trials riders would demand manufacturers engineer rim brakes for their motorcycles. I haven't seen any of that.

The one argument for rim brakes I can see is on 20" wheel bikes where their axles are low to the ground so disc brakes might get damaged. Also rim brakes and mechanical discs are cheaper so if money is an issue then better to ride mechanical than not ride.

In the end I'm sure modern rim brakes work fine and if that is what you like run them. I'm just saying they don't work better and aren't easier to maintain.

I am sorry ,but this has annoyed me a bit.

I have been riding trials for nearly 14 years, I have tried and experimented with all kinds of things on bikes (made my own rigid forks from suspension parts, welded rims together to make light wide rims, cut and shut disc systems etc).

It annoys me greatly when someone with not much trials knowledge waltzes in and thinks they know best....you don't!

I am a profesional wheelbuilder for a well know bike company, you can't say spokes don't flex. the rigid mtbers may be making up excuses for not making it up the hills, but that isn't trials. Trials demands a whole new level from nearly every part of the bike. The flex in spokes is enough to take the "feel" out of the rear wheel when you need to be pin point accurite 10ft up on things barely bigger than your tyres. Unless you are riding in these conditions, don't make asumptions.

As for actual braking power, I had a Saint, and very powerful it was too, I have also had a BB7 and that was on par with the Saint plus it was more adjustable. We use stuff that works, get off your high horse, just because we use cable brakes doesn't make us un educated morons. Just because I can't bleed a car brake doesn't mean I can't bleed a MTB brake.

Can I hazzard a guess that you are an enginner by trade?

Discs on mod are fine, you can use smaller rotors as the wheel doesn't have as much mechanical advantage.

[forteh]

The feeling of spoke flex with a rear disk brake on stock is like riding on a mattress, it is constantly flexing (both the spokes and the disk itself) and just feels vague as ali pointed out. No matter how good your wheelbuild is, you still have flex in there. Spoke flex doesnt really directly affect the performance but it certainly make the bike feel disconnected from the ground when on one wheel.

You could almost go as far to say that spoke flex with a rim brake will actually increase performance because you can preload the spokes through the drivetrain and release it when the brake is released (along the lines of the cousts running super slack chains because it gives them a bit more whip in the pedals to build up inertia). With a disk brake the opposite would happen and preloading the chain would have less of an effect, indeed the spokes flexing would absorb some of the preloaded power.

Rim brakes for mototrials cant work because of the relative weights and inertia involved, however theyre not going to complain about spoke flex because the rear wheel is so loosely connected to the frame (by means of suspension) its not an issue, additionally the spokes are a hell of a heavier gauge. Offer a heavy enough guage spoke (in order to stop spoke flex) to a bike trials rider and they will probably complain that the wheel is too heavy and too energy sapping.

Not sure where youre coming from with people being scared of brake fluid, a hell of a lot of people use dot fluid systems (primarily hopes). The reason the bb7 is so popular is because its cheap, bites and holds exceptionally well; these arent qualities wanted for an xc/dh rider because they want modulation not instant wheel locking.

At the end of the day most of the top level competitors in trials use rear maguras over disks. Lighter, more bite and a more positive feel for where the rear wheel is

edit: dammit ali typed faster than me! Youre right though, trials isnt like any other form of cycling and different things work when they shouldnt but hey leave us engineers alone

Edited November 5, 2010 by forteh

[Sad Clouds]

Ali C, I probably have a slightly biased opinion, because I don't have much experience with rim brakes, however I'm quite interested in the science of wheel building. My wheels were built by someone at Tarty Bikes, perhaps you or Adam and I think you guys did a superb job. The rear wheel was Chris King 36H hub and Sun Ringle MTX rims, laced 4-cross with Sapim Strong spokes.

I don't really notice any spoke flex, but then I'm not too picky on these things. I did a fair amount of research before I ordered the parts. My understanding was that using a hub with wide flanges, strong spokes, and 4-cross lacing pattern, results in extremely rigid wheel. I think mainly this is because the hub pulls on the spokes at the right angle. Maybe I'm missing something, but I can't see how you can get a noticeable spoke flex, since the twisting force exerted by the hub is done at such an angle that the spokes are being stretched at the same angle as they are pulling on the rim.

[Dwarf Shortage]

If rim brakes were better motorcycle trials riders would demand manufacturers engineer rim brakes for their motorcycles. I haven't seen any of that.

LOL.

Saying that just because one thing is better suited to one application, it should be used in every application possible is like eating popcorn chicken from a hollowed out baby.

And you can't vouch such a strong opinion for disc brakes' superiority over hydraulic rim brakes, considering you've never even used them.

[modifier]

I'm sure you guys have years more experience with trials. It just isn't very popular in the US and I also haven't personally concentrated on it. But I do have a lot of bicycle experience and to me brakes are brakes and have one function, but perhaps trials braking is different. I have been riding off road for 38 years and built up my first trials bike when I was 12 in 1972 then started racing gas MX in 74. I began riding mountain bikes in 1981 and have been ever since. I've designed an built my own bicycle components as well over the years and most things I've experimented with have become industry standard years down the road. I've worked as a bike mechanic and have built many wheel sets.

I was never very good at hopping around on a bicycle so I can't actually speak to what wheel flex feels like when hopping on the back tire and how it differs with disc brakes because I can't do it. So I grant you that perhaps it's a whole different world and if I could perform at that level I might agree with you.

My Saint brakes easily lock up completely as far as I can tell and when I ran BB7s they did not have close to the same gripping strength. I had the same experience with rim brakes for many years. But then I wasn't using them with 20" wheels. So, again, maybe that makes it all different.

I believe in mechanical technological advancements particularly with bicycles so when people talk about how older technology is better it's hard for me to keep quiet sometimes. I guess I should not voice my opinion unless it is in line with the collective or expect to get flamed.

I've been thinking lately that I might build up a 26" trials bike since they have gotten so specialized and functional so if I do maybe I'll run hydraulic rim brakes on the rear and a disc on the front to see how well they work.

I'm not a trained engineer btw.

[Kieran Morrison]

If rim brakes were better motorcycle trials riders would demand manufacturers engineer rim brakes for their motorcycles. I haven't seen any of that.

Not really, most discs tend to have a better hold than rim brakes, so an extremely heavy motorbike on top of a magura hs33 isnt gonna work.

And you said earlier in that post, that an avid bb7 works worse than a rim brake, I don't know what bb7 you used, but the bb7 is arguabley the best disc brake out there for push trials bikes (the hope mono is also known to be good)

Anyways, disc or maggy is a hard question, and at the end of the day its personal preference. Discs have their advantages vice versa, i use a maggy but will admit discs are far more sutied to my riding. Wish I got a rear disc echo now, as i like to ride in the rain and hate the maintinence (sp?) from a maggy.

There is nobody who can say 'discs are better' and nobody who can say 'maggys are better'. All personal preference...

And discs are quiet.. You gotta love a quiet brake!

[modifier]

Not really, most discs tend to have a better hold than rim brakes, so an extremely heavy motorbike on top of a magura hs33 isnt gonna work.

And you said earlier in that post, that an avid bb7 works worse than a rim brake, I don't know what bb7 you used, but the bb7 is arguabley the best disc brake out there for push trials bikes (the hope mono is also known to be good)

Anyways, disc or maggy is a hard question, and at the end of the day its personal preference. Discs have their advantages vice versa, i use a maggy but will admit discs are far more sutied to my riding. Wish I got a rear disc echo now, as i like to ride in the rain and hate the maintinence (sp?) from a maggy.

There is nobody who can say 'discs are better' and nobody who can say 'maggys are better'. All personal preference...

And discs are quiet.. You gotta love a quiet brake!

Well actually I meant an appropriately scaled rim brake for motorcycles rather than a disc brake. There was the old argument that was around when bike discs were emerging that a rim brake is just a big disc brake, which is true, but other problems arise with that scenario that have been brought up like gripping surface (the rim) having to be clean, dry, scuffed and true, and pad material. I remember in the old days always having to mess with rim brakes to keep them adjusted and as quiet as possible which was usually impossible. Maybe pad material has been improved and they are easier to tune now.

I also didn't mean to imply that I thought bb7s were worse than rim brakes. I said that bb7s and rim brakes in my experience were inferior to hydraulic brakes that I have used. On the other hand I have an older Cannondale with (old technology) Coda hydraulic brakes that are just shy of worthless. Noisier than any brakes I have ever used and almost no stopping power so I'm going to switch those out with my set of bb7s which I'm sure will be better and it's just a commuter bike anyhow. So I guess not all hydraulics are good; I've just had good luck with all the others. And apparently 20 years of bad luck with rim brakes. Which brings up another possibility. I haven't tried very many different manufacture's disc brakes. My first 2 disc sets were first generation Hayes which worked better than rim brakes but were a bit problematic at times when they got old. Then I switched to Shimano and and have always used either XTRs or Saints ever since, which are both their top of the line brakes, so maybe there are a lot of there hydraulic brakes out there that don't work very well and I haven't experienced them. Oh yeah and one set of Avid Ultimate Carbons that work great from a couple of years ago that replaced the bb7s. I've heard that Codes work well too.

Then once again perhaps really hard core trials ridding does introduce effects that I can't recreate with other types of riding making rim brakes work better for that application.

Edited November 6, 2010 by modifier

[Kieran Morrison]

Wouldn't really say thata rim brake is a big disc brake, but okay, everyones entitled to their own opinion.

Are you a bike/motorbike mechanic, engineer or something? You seem to know ALOT about motortrials and normal trials, and brakes etc.

[Andrew C]

LOL.

Saying that just because one thing is better suited to one application, it should be used in every application possible is like eating popcorn chicken from a hollowed out baby.

Haha thats epic, i think i just pissed myself

[ginger trials]

I find that one of the problems i have with my disk brake is that once it gets hot it looses its sharpness,and that doesn't happen on my rim brake it just needs replacing a lot more than the disk brake does.

[JD™]

So basically what you're doing is coming onto a forum full of people who have experimented with various different braking solutions to find those which are best for their particular function, whilst having no ability in that particular function yourself, and preaching to us?

Kindly, f**k off.

Trials riders have, historically and presently, tried every type of braking solution you know of as well as some you don't. We've then put those solutions into practise, to get away from theory. Your theory is useless in the presence of tested fact.

Edited November 7, 2010 by JD™