Cycling UK Forum

Is Sheldon Brown right?
http://sheldonbrown.com/brakturn.html

I think not.

Two brakes are always better than one. If your rear wheel lifts, you're not doing it right. Sit back, shift your weight, give your rear wheel some grip.

I think Cap'n Bike has it right, with good grip and putting your weight as far back as you can your front brake should still be powerful enough to lift the rear wheel. If you're not sure look at MotoGP racing bikes, they don't use the rear brake at all in the dry, the front brake is easily capable of flipping the bike base over apex.
However that's for a perfect emergency stop. Anything less than an all out attempt or an all out attempt on a less than perfect surface means your back brake has work it can usefully do, so it should be used. It all depends on how you define stopping I suppose.

Having read the article, I think that in the dry he is probably correct in some ways, but I don't agree with getting used to only braking with the front.

The weight transfer, under extreme breaking when the front wheel has a lot of grip, will mean that the front wheel has all the grip and the rear has very little.

However, I don't agree that it is best to brake using only the front brake. Under gentle braking I think it is best to use both brakes to reduce heat build up and wear on both wheels. As heavier braking is required, more front and less rear is required. When emergency braking is required it is much easier to control a bike with momentary rear lock up than if the front locks, so it must be better to use the rear as much as possible to reduce the chance of a front wheel lock up..

In adverse conditions, just using the front is dangerous, as the weight transfer is much less and the risk of the front locking is increased. Use of both brakes is advocated by Sheldon Brown in poor conditions, but as you say Mick I think it is best to use both and to learn to adjust the riding position and brake force to suit the conditions encountered rather than leaving the rear brake for dangerous conditions that are rarely encountered.

downsman wrote:........I think it is best to use both and to learn to adjust the riding position and brake force to suit the conditions encountered rather than leaving the rear brake for dangerous conditions that are rarely encountered.

Nicely put.
My sentiments entirely!

Having snapped a front brake cable while heading toward a busy dual carriage way I'm glad that I had a rear brake too!

Si wrote:Having snapped a front brake cable while heading toward a busy dual carriage way I'm glad that I had a rear brake too!

very, very true, and also for fixed

For speed control, rather than outright stopping, the front brake alone throws weight to the front, both brakes together keep the weight distribution even, so it's sensible to be in the habit of using both together for those occasions when you unthinkingly brake when cornering & the surface is a bit dodgy....

Mick F wrote:Is Sheldon Brown right?
http://sheldonbrown.com/brakturn.html

I think not.

Two brakes are always better than one. If your rear wheel lifts, you're not doing it right. Sit back, shift your weight, give your rear wheel some grip.

Actually he is right. In your case, Mick F, you can shift your weight back and lower even further, and then apply your front brake even more. This argument can be applied ad infinitum. This applies to an emergency. There are of course other arguments about balance when wishing to continue or turn or whatever sophisticated turms you wish to make. BUT, there is a very good reason why cars have bigger front brakes and smaller rear ones, but don't confuse balance and manoeuvrability with pure stopping power.

Temperatures - an interesting point in theory. In reality, how many riders know how hot their brakes are, or at what temps their brakes will fade or fail?

Sheldon's point is true for that very precise condition of applying the front brake right up to but not actually reaching slipping point or even cleverer lifting the rear wheel.
However most of us are not that good most of the time. The danger of over applying the front brake is such that we only apply a fraction of the braking available from the front brake and there is still enough weight on the back for it to have an effect.
Personally I dream of being on a road where I can use even half of my front brakes capacity, the rural world has too much diesel, gravel, water and mud.
Also there is the point (learnt the hard way), if a vehicle pulls out in front of you and you brake hard on the front and lose control and hit the floor, the car drives away leaving you with the repair bill. If on the other hand you do a more controlled deceleration and stay upright and collide with the car at low speed, you can then take them to court for the damage and maybee even the Police will act against them.

PW wrote:...both brakes together keep the weight distribution even...

I don't think that's quite true - the deceleration alone will weight the front wheel more, whichever brake(s) is applied.

downsman wrote:When emergency braking is required it is much easier to control a bike with momentary rear lock up than if the front locks, so it must be better to use the rear as much as possible to reduce the chance of a front wheel lock up

Definitely not! The rear wheel will simply try to slide past the front and you will lose control. Front wheel lock is surely unlikely unless on a poor surface.

I agree with Sheldon; most of the comments about loose or wet surfaces, rim heating, etc. are mentioned in his article.

I wrote a little report a good few months back about braking.

I carried out an experiment, and asked others to try too. No-one took me up on it. If I took the time, I could dig out my post.

It went something like this:
I found a gentle slope that I could repeat the trial over and over from the same place at the same speed.
I repeated three times each test, and measured my stopping distance.
I did rear only, front only and both.

Rear only was rubbish, as you would expect.
Front only was excellent.
Both was even better!!!!

And why shouldn't it?
Yes, I agree that in hard braking, the rear lifts and doesn't provide much braking and could lock up, but BEFORE the weight shifts, it MUST provide a good effect to slow you down. If you can stop the rear from lifting, like I do, then even with a locked rear wheel, the bike stops quicker with it than without it.

Try an experiment. Go on, try it! Prove me wrong.

Andy,
I disagree on both cases (as seen in my almost coincidental posting)

On the advanced motorcycle training we were taught to come to a final halt on the back brake as it lifted the motorbike up on the front forks and avoided the unsightly bouncing back and forwards caused by someone who stops on the front brake.

I have done emergency stops on a motorbike which caused a "stoppy" like a wheely in reverse. However that was very rare normally the front wheel went down underneath way before all the weight was off the back tyre.

As for a back wheel locking up we have all been there and if it is only the back wheel which is being braked then it always skids along behind. Almost everyone can react quick enough to release a skiding back wheel.
Front wheel skids are much more rapid in bringing you down.

Same goes for punctures.

Sorry Mick your test was flawed. You were not applying the front brake hard enough. The only way you can know you had applied the front brake hard enough is if it had been applied a tiny bit too hard and you had crashed!
On the other hand your test was perfectly valid as it shows the real life acheivable and controllable braking by a normal person on a normal surface is by a responsive application of both brakes.

http://forum.ctc.org.uk/viewtopic.php?p ... ght=#34666

Found it.
Nobody took me up on a test themselves.
Come on, facts please.
Try it.

meic wrote:On the advanced motorcycle training we were taught to come to a final halt on the back brake as it lifted the motorbike up on the front forks and avoided the unsightly bouncing back and forwards caused by someone who stops on the front brake.

Okay, so essentially a force is being applied towards the bike (from front or rear braking). Since no force is being applied to the rider, if he/she is to avoid continuing at the same speed (and parting company from the bike!) an equal force must be applied to him/her. This can only come from the rider bracing against the handlebars, which applies force onto the front wheel of the bike. No?

meic wrote:I have done emergency stops on a motorbike which caused a "stoppy" like a wheely in reverse. However that was very rare normally the front wheel went down underneath way before all the weight was off the back tyre.

I'm not sure the weight distributions, etc., allow a fair comparison here. I'd expect a similar situation when braking with an occupied child seat (in which case I use front brakes, applying rear if that proves insufficient), but not a simple bike and rider.

meic wrote:As for a back wheel locking up we have all been there and if it is only the back wheel which is being braked then it always skids along behind. Almost everyone can react quick enough to release a skiding back wheel.
Front wheel skids are much more rapid in bringing you down.

I'd certainly agree with this, but on good tarmac, I think front wheel skidding is unlikely.