Back Brake - You better stop me .....

Bloody hell you blokes have been buisy over the weekend hey?
I'm the first to say I'm not an expert or particulary fast rider but I try hard and I've played around with this.
Fact: the front brakes provide 70% of all braking power. That means that the rear can offer upto 30% of the stopping power.
Those of you who have done your licencing with with H.A.R.T. would remember the emergency stopping drill. As a group we had to decide where the instructor would stop using rear only, front only, and front + rear. Believe me that both brakes together have a substually better stopping distance. I watched, then tried. Since tried it again recently as well. Can't despute the results.
So transfering this to fast riding (not necasarily appropriate for public roads) it menas that you can go further under power before applying the brakes deep into the corner.
Too much front brake can do a couple of things:
- It can create too much weight ransfer and overwhelming the grip provide by the front tyre.
- it can also cause the rear of the bike to walk and step out sideways as the rear tries pass the front
- or it will dance and start to leave the groung all together.

However a LITTLE rear brake will settle the rear of the bike keeping it inline and in contact with the road.
A substantial amount of rear brake wkile traveling in a straight line WILL have dramitic effects on stopping distance.
BUT, you don't have the same dexterity or feel with your feet as you do with your hands so it takes practice to get it right.
A little more rear brake can have you backing into to corner like pro, don't know that its any faster but crap its fun. Too much rear brake mid corner can end in tears though.

So what do I do?
Well as Rob, Scotty and Mario can probalt attest to, I aproach the corner pretty hard using both brakes. then I'll let the fronts off as I begin to turn in but leave the rear on fractionaly longer before easy it right off before mid corner and feeding in the gas again. I've found that this helps stop the rear trying to pass the front.
In the wet I only use it extremley gently to try and stop loading up the front too much, but only in a straight line. I also use it heaps lane splitiing or aproaching lights when Im sitting up having a rest or stretch.

Right or wrong, this what I do. As I said I use 1 set of rears for every three fronts. That means I'm upto 3 sets of rears 7 fronts.

i like this thread.

there are some good pointers to try/keep in mind from people who have been riding for ages.

excellent work.

someone who forgot his rear brake.....hehe

ouch.........

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Last edited by Smitty on Mon Sep 27, 2004 8:41 am, edited 2 times in total.

Now master Yoda Sir ... you had your go and made some good points thanks heaps .
Now would you mind ever so slightly Buggering off so I/We can keep learning from others Experience/s.
cheers Brett'
Ps Mate a Jumbo 747,s Back Break wouldnt of helped avoid that, as I'm sure RedSean could testify too.

well at least...its not a Kawasaki
looks like a Hond..Hoonnd...Hondras...yeah, one of them

the rear tyre looks alright perhaps he could sell that!!

thats looks bad.

crash course on how to learn to fly
pardon the wording

From my experience, the front brake has 2 discs for a reason, it's the most efficent way of slowing down when travelling at reasonable speed, but in applying it, the bike pivots on the front wheel, which increases the centre of gravity.

The rear has the effect of pivoting on the rear tyre, which lowers the bike, decreasing the CG, this can be VERY useful for tighting a turn - as well as more forgiving if it locks up.

I've done over 70,000 km on my 9R and still have the original rear pads (plenty of wear left too), where as I'm on my third set of front pads.

The rear wheel will make you go and the front will stop you.

I use the front even in wet/slippery conditions, just alot more gently and tend to use the engine rather than the rear brake, as it's alot more controllable.

So that's my 2c (seasonally adj and rounded to 5c)

I've done over 70,000 km on my 9R and still have the original rear pads (plenty of wear left too), where as I'm on my third set of front pads.

um - wow.
In ~40000kms I've gone through multiple sets of both. Can't remember exactly but at least 2 rears and 3 fronts. I'm impressed.
ty

From my experience, the front brake has 2 discs for a reason, it's the most efficent way of slowing down when travelling at reasonable speed, but in applying it, the bike pivots on the front wheel, which increases the centre of gravity. The rear has the effect of pivoting on the rear tyre, which lowers the bike, decreasing the CG, this can be VERY useful for tighting a turn - as well as more forgiving if it locks up.

The rear wheel will make you go and the front will stop you.
I use the front even in wet/slippery conditions, just alot more gently and tend to use the engine rather than the rear brake, as it's alot more controllable.

hmmm.....and imho
me thinks, a cupla contradictions here
Engine braking has exactly the same effect as the back brake
....it slows the back wheel
also
up to a point, a bike with only one disc will stop as well as a bike with 2 discs, especially if either braking system has the ability to overcome the tyres coefficient of friction (lock the wheel if you like)
however, a 2 disc system will require less line pressure and therefore less pressure on each brake pad to equal the equivalent stopping power of a 1 disc system and this will also create less heat to stop the bike compared to a 1 disc system, which is why race bikes (and most road bikes)use 2 discs, not 1, despite the disadvantage of extra weight and the extra force (centrifugal force) from a 2 disc system
also
the CofG is decreased when you brake using either brake
both use of front or rear brakes cause a bike to go lower (down goes the CofG), its how the bike reacts that is the difference!

use of the front brake causes the transfer of weight to the front, the front suspension to reduce in height (compress if you like) and the rear to rise
This steepens the steering angle, compresses the front tyre and makes a bike more flighty and more difficult to steer when braking, it also increases the slip angle of the front tyre and can cause a low side (if you turn)
Use of the rear brake causes the rear to squat (maybe marginally)
which causes the angle of the steering head to lessen (assuming the front does not rise) which changes the trail and makes the bike easier to steer
which makes the bike easier to turn

the physics of biking is a wonderful subject!
yoda will now wait for other comments on this
apologies for the length of this
interesting post flakey!

cheers

yoda will now wait for other comments on this
apologies for the length of this
interesting post flakey!

If I was a newbie, I'd be thinking, "what the hell did all that complecated drival just mean."
I understand the principles here and you still manage to confuse the shit out of me.
The effect of wieght transfer on suspension geometry is fuck all. The point of a good suspension set up is to cope with all this.

what the.. i hit the front brakes mid corner and my bike does NOT stand up - rather, it holds its line, and thats how i like it. its a matter of suspension - if i'm wrong, would an expert please correct me, not some newbie fresh off his training wheels. my bike DID stand up under front brakes thru corners, but the suspension was like, totally out of whack, and after a lot of guesswork and adjusting, i think ive got it close to being perfect.

rear brakes - flakey, 70,000km and 3 sets of fronts and still on the original rear pads? you dont use them enough.. do your front discs wobble at speed? if they dont, then you probably dont venture over 100kmh much, if at all.. a postie might be worth it, cheaper rego and insurance

i used to be hard on my fronts, paid the price and had to get a set of replacement discs much earlier, and learnt my lesson - the back brake is a valuable asset to a bike in more ways than one. like TY said, its there for a purpose. so i barely touch the fronts unless i absolutely have to, the rears get used in the majority of the time.

maybe some people need to ride their bikes.... like the manufacturer intended.

oh by the way, i agree with what ian's said in his physics post. almost all.

jason, ANY bike is easy to ride fast if its' suspension is set up PROPERLY.

if i'm wrong, would an expert please correct me, not some newbie fresh off his training wheels.

Ooohh, another touchy old man. If you actually read the intent at the beginning of the thread, you see that the purpose was for the NEWBIES to discuss and get some ideas on things to try.
Sad sack.

Last edited by mattyv74 on Mon Sep 27, 2004 11:29 pm, edited 1 time in total.

I aint no Valentino Rossi, but here's my opinion.

neither am i..im better
but seriously..i use my rear for slow speed manouvres, controlling wheelies, and stopping when im show-ponying (riding no hands,using clutchless downchange & rear brake only, and coming to almost a complete stop b4 grabbing a handful of clutch)...if i think im too hot, i just lean more, tho sumtimes they fall over wen i do that (front tyres really need to b warmed up b4 u go fast)....actually im not the kinda rider u wanna base urself on, im technically crap, but i enjoy it, im not fast, but im not slow, im a bit cautious tho now..damn i want insurance!!
ive been thru 3 sets of front pads & 2 rears in 30,000km , mostly cos i do a lot of stupid shit...ive been riding since i was 5...got my L's at 17...full lic at 19 ( i lost my P's for a 106km/h in a 50zone on double points with a week to go on a mates TZR250 & had to start again on my P's..ive always been stupid..was born that way & just grew bigger)
neka
p.s. dont take ne notice of my technique, just laugh at my stupidity...