Open letter by Vents regarding disc brakes **Graphic photos**

[Patchelicious]

Its not all about braking power. MTB's may have better grip but the surface they are used on often doesn't. I think discs have far better modulation which means more accurate brake control.

Exactly! I can remember stealing my dads old Corolla ages ago to take on joyrides. We would lock the wheels up at each corner pretending to be Colin McRae..... It had drum brakes, yet enough power to lock the wheels up. Yet discs perform better and are now the accepted norm.

 

Grip between tyres and the road is one of the factors to be considered. However there are other factors at play too. One cannot ignore things like better modulation, feel, confidence, consistency etc when talking about an over all better braking performance.

 

This is a nice real world test when the human factor is included.

 

[Patchelicious]

This is also a cool video:

 

[carbon29er]

the ah ha moment will come when tyres are able to deliver the level of grip required for any brake to be more effective. Rim brakes have more than enough braking power and have far superior braking torque than a disc since the application of force is further from the centre of rotation.

the advantage of discs is that the braking surface does not deform or strain  parallel to the brake force application like a rim brake.

But we've not reached that limit yet because the tyres don't offer enough grip.

 

 

Its not all about braking power. MTB's may have better grip but the surface they are used on often doesn't. I think discs have far better modulation which means more accurate brake control.

 

The tyre argument is only used by those who have no idea about how much more effective disc brakes are than rim brakes. As proven over a decade or so on MTB, pointed out by Headshot. In the same way it's still possible to lock up a motor vehicle's wheels with disc brakes as the tyres eventually reach an adhesion limit but who, other than an idiot, would argue drum brakes are superior as you don't reach that lock up point as rapidly?

 

Raptor-22 Do you honestly push your brakes as hard as you can when you brake in your motor vehicle or do you feather them with the appropriate pressure to slow down or stop? Why is a bicycle any different? And disc brakes do this better than rim brakes.

 

Another benefit is losing that ugly braking surface on the rim, my wheels look a lot nicer being uniform from the tyre to the spoke hole.

[Pure Savage]

I see America has not banned them as they say there is no evidence, France and Belgium have banned them, and the UCI is now lifting the ban. What a dog show.

[carbon29er]

I see America has not banned them as they say there is no evidence, France and Belgium have banned them, and the UCI is now lifting the ban. What a dog show.

Does SA even know they exist?

[Pure Savage]

Does SA even know they exist?

 

Well, if you travel to do a sportief or event in France that is sanctioned you may not do it on a disc brake bike as they are now banned, so may affect some peeps in SA. 

[carbon29er]

I meant CSA...

 

It is incredible how little progress Brian Cookson has made as UCI President. The sport is still stuck in the past era of self interest of the administrators rather than encouraging the riding of bikes. In any form.

[Pure Savage]

I meant CSA...

 

It is incredible how little progress Brian Cookson has made as UCI President. The sport is still stuck in the past era of self interest of the administrators rather than encouraging the riding of bikes. In any form.

 

I see what you mean, maybe CSA just want to stay under the radar so they dont get picked on by our sports minister!!

 

If you want to see the best administered sport in the world, check out Ice Hockey:

 

http://www.iihf.com/fileadmin/user_upload/PDF/Sport/Coaching_manuals/1_Level_II_Structure_of_IIHF.pdf

 

They own the rights to TV for world champs each year, they then use this cash from the top tiers to fund ALL the other world champs each years, Male and female, each age group (U18, U20, Open) and all tiers (1A, 1B, 2A, 2B, 3A). So close to 30 world champs each year so the orgainser make a small profit for their local assocation. Maybe R50k. They also then give each team competing in those world champs (6 teams per world champs) money to get to the world champs. 

 

That is how a sport is run. Imagine our cyclists being paid to go to the world champs by the UCI. 

 

*They also fund massive learn to play programs, holding international clinics and pay for members to send 2 or three players a year to the camps. They also send "Africa - SA" container loads of kit for 4-8 years olds as its the biggest barrier to entry in the sport. Its another level.

[raptor-22]

The tyre argument is only used by those who have no idea about how much more effective disc brakes are than rim brakes. As proven over a decade or so on MTB, pointed out by Headshot. In the same way it's still possible to lock up a motor vehicle's wheels with disc brakes as the tyres eventually reach an adhesion limit but who, other than an idiot, would argue drum brakes are superior as you don't reach that lock up point as rapidly?

 

Raptor-22 Do you honestly push your brakes as hard as you can when you brake in your motor vehicle or do you feather them with the appropriate pressure to slow down or stop? Why is a bicycle any different? And disc brakes do this better than rim brakes.

 

Another benefit is losing that ugly braking surface on the rim, my wheels look a lot nicer being uniform from the tyre to the spoke hole.

 

 

Actually I use thebraking style that appropriate for the situation, most of the time I'm not using the brakes at all cos I'm regulating my speed according to traffic.

 

As far as modulating my braking on a road bike, I do that pretty well with rim brakes thank you.

 

I have no challenge to disc brakes being better in the wet. But I very seldom ride my raod bike in the wet thanks to the lunatic drivers we have down here in Cape Town.

 

Would I buy a road bike with disc brakes? Yes most certainly, if it was allowed to be used in UCI sanctioned events.

Do I think disc brakes are necessarily better? Only in the wet. I have never had problems with modulating cable pulled rim brakes from Shimano, Campagnolo, SRAM, AX-Lightness or anyone else. Comparing a 85Kg vehicle and driver to a 1500kg vehicle and driver is simply moronic. The vehicle dynamics are very very far apart.

BTW comparing a rim brake to a drum brake........really, are you that desperate ?? Weak argument. A rim brake can be viewed as a disc brake with a very large rotor. A drum brake cannot

 

BTW a Batavus commuter I had some years ago was fitted with drum (hub) brakes in front and rear. They were more than powerful enough to stop a 90kg rider /bike combination safely quietly and quickly every time.

[Patchelicious]

Actually I use thebraking style that appropriate for the situation, most of the time I'm not using the brakes at all cos I'm regulating my speed according to traffic.

 

As far as modulating my braking on a road bike, I do that pretty well with rim brakes thank you.

 

I have no challenge to disc brakes being better in the wet. But I very seldom ride my raod bike in the wet thanks to the lunatic drivers we have down here in Cape Town.

 

Would I buy a road bike with disc brakes? Yes most certainly, if it was allowed to be used in UCI sanctioned events.

Do I think disc brakes are necessarily better? Only in the wet. I have never had problems with modulating cable pulled rim brakes from Shimano, Campagnolo, SRAM, AX-Lightness or anyone else. Comparing a 85Kg vehicle and driver to a 1500kg vehicle and driver is simply moronic. The vehicle dynamics are very very far apart.

BTW comparing a rim brake to a drum brake........really, are you that desperate ?? Weak argument. A rim brake can be viewed as a disc brake with a very large rotor. A drum brake cannot

 

BTW a Batavus commuter I had some years ago was fitted with drum (hub) brakes in front and rear. They were more than powerful enough to stop a 90kg rider /bike combination safely quietly and quickly every time.

There was not a comparison being made between rim and drums. The comparison was drums vs disk.

 

The point being illustrated was in response to you saying you will consider disk brakes once tyres can cope and that rim brakes have enough power.

 

"the ah ha moment will come when tyres are able to deliver the level of grip required for any brake to be more effective. Rim brakes have more than enough braking power"

 

The disk vs drum thing is relevant, because drum brakes also have enough power to over come the grip levels of a tyre. But as mentioned a few times, if braking power was the only thing to consider then disk would never have taken over from drums in cars.

 

And again, nobody is comapring bikes to cars "like for like", rather its the idea behind it about brake force not being the only thing.

[raptor-22]

There was not a comparison being made between rim and drums. The comparison was drums vs disk.

 

The point being illustrated was in response to you saying you will consider disk brakes once tyres can cope and that rim brakes have enough power.

 

"the ah ha moment will come when tyres are able to deliver the level of grip required for any brake to be more effective. Rim brakes have more than enough braking power"

 

The disk vs drum thing is relevant, because drum brakes also have enough power to over come the grip levels of a tyre. But as mentioned a few times, if braking power was the only thing to consider then disk would never have taken over from drums in cars.

 

And again, nobody is comapring bikes to cars "like for like", rather its the idea behind it about brake force not being the only thing.

 

 

If Carbon is not comparing then he shouldn't try to draw similarities... plain and simple. Didn't realise you were his defense attorney.

 

Disc vs drum in cars is a massive difference because the limit of forces being applied vs the energy that needs to be absorbed is vastly different than for a bicycle.

Enough force is enough force and quite simply, drum brakes in cars do not exert enough force with servo assist (booster)  to slow down the mass. This is due to a smaller effective diameter of the braking surface and heat build up. The drum also needs to be heavier to prevent distortion due to the applied force. In a bicycle application drums do work well enough because you are not slowing own as higha load from a veryhigh speed. Much less energy to absorb.

A higher theoretical upper limit for a disc is irrelevant if there are alternatives that provide sufficient stopping power at a lower cost and lower maintenance.

 

BTW, disc brakes gained popularity not because of greater stopping power bu because of ease of maintenance. The clamping power from a disc brake comes from the servo assist which boosts the force on the brake piston. The same principal can be applied to a drum brake with similar stopping power achievable.

The challenge is dissipating heat and maintenance is a bitch.

FOr bicycles, rim brake maintenance is not an issue and having the braking surface close to the tyre mounting area makes for a very strong rim. Removing that material and strength would do what for strength and safety of the rim?

 

Please continue

[Patchelicious]

If Carbon is not comparing then he shouldn't try to draw similarities... plain and simple. Didn't realise you were his defense attorney.

 

Disc vs drum in cars is a massive difference because the limit of forces being applied vs the energy that needs to be absorbed is vastly different than for a bicycle.

Enough force is enough force and quite simply, drum brakes in cars do not exert enough force with servo assist (booster)  to slow down the mass. This is due to a smaller effective diameter of the braking surface and heat build up. The drum also needs to be heavier to prevent distortion due to the applied force. In a bicycle application drums do work well enough because you are not slowing own as higha load from a veryhigh speed. Much less energy to absorb.

A higher theoretical upper limit for a disc is irrelevant if there are alternatives that provide sufficient stopping power at a lower cost and lower maintenance.

 

BTW, disc brakes gained popularity not because of greater stopping power bu because of ease of maintenance. The clamping power from a disc brake comes from the servo assist which boosts the force on the brake piston. The same principal can be applied to a drum brake with similar stopping power achievable.

The challenge is dissipating heat and maintenance is a bitch.

FOr bicycles, rim brake maintenance is not an issue and having the braking surface close to the tyre mounting area makes for a very strong rim. Removing that material and strength would do what for strength and safety of the rim?

 

Please continue

Actually no thanks, you do not seem capable of constructive debate without insulting people, so I will rather refrain from engaging with you.

[raptor-22]

were have you been insulted?

rather sensitive for someone who likes to play the man and not the subject

[carbon29er]

 is simply moronic.

 

.really, are you that desperate ?? Weak argument. A rim brake can be viewed as a disc brake with a very large rotor. A drum brake cannot

Clearly you forgot what you wrote about traction and tyres. So the insults start flowing. This inability on your behalf to read a rebuttal of your original argument reminds me of what Samuel Clemens once wrote.

[raptor-22]

The argument for Tyres being a limiting factor still holds true. What would you like to debate about that. You threw the insults. Go back and read what you wrote

[GLuvsMtb]

Oooh! Handbags and its only Wednesday? As you were ladies!