... while cars don't have similar feature?
PS: I heard that in N America, front brakes on bikes are on left hand side (opposite to ours!)
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Moto Guzzi and others had one front disc connected to the back brake;excellent when you got the hang of it.
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Having only two wheels with which to stop yourself requires more skill than just planting your foot on the brakes in a car... if you get it wrong you're likely to end up on your bum!
I had a few bikes where they had front discs (very good) and rear drums... in certain conditions it is better to rear-wheel brake (where all the weight is) rather than have the fronts lock up and you end up in a slide or a spectacular weave!
So the answer is, to allow more flexible braking by the rider...
Edited by b308 on 07/01/2009 at 16:07
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A bit OT, but I have a 1920s Adler ladies bike that has a back pedal rear brake, and the front brake is a rod/lever down to a rubber-covered shoe that acts directly onto the front tyre through a hole in the mudguard. About as much use as a chocolate fireguard.
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< while cars don't have similar feature?>
I've got one that does! My 1930 Morgan trike, as per original has a hand lever operating the front brakes, and a foot pedal operating the rear. I think front brakes were an option from 1923 and standard from 1926. While I'm not complaining possession of a driving licence has little to do with being able to drive one safely!
Modern coupled brakes are much better.
(edited for dyslexia)
Edited by SlidingPillar on 07/01/2009 at 16:32
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A bit OT but I have a 1920s Adler ladies bike that has a back pedal rear brake and the front brake is a rod/lever down to a rubber-covered shoe that acts directly onto the front tyre through a hole in the mudguard. About as much use as a chocolate fireguard.
I've got one of those too - with a loop-frame?
The front brake is for parking only - so that the bike doesn't run away while you are trying to get on.
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As b308 says, much more control is needed on two wheels especially on loose surfaces when a front wheel is easily locked up, not recommended at any speed. Honda use a linked braking system which brings both back and front brakes on together regardless of whether you apply front or rear brake. I had a VFR 800 as a loan bike with this system and it was very strange to begin with but soon got used to it. The bike also had ABS so front wheel lock ups shouldn't have been a problem.
Early Triumphs also had the brake lever on the left and gear change on the right. Some bikes also had the gear box back to front as well. Up for first gear and then down for the rest. You had to be very careful changing gear especially at higher speeds. You don't want to hit 2nd instead of 4th at around 70mph !!!!!
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To clear up a few points, ALL motorcycles have have the front brake on the right for many years, no matter what continent they are made in (Indian used to have the throttle on the left, no wonder they went bust).
The gearchange on GP bikes is lever down to change up, as upshifts are much faster that way.
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PS: I heard that in N America, front brakes on bikes are on left hand side (opposite to ours!)
No, you heard wrong IMHO. I heard some very old US police bikes had the throttle on the left to allow the use of a pistol in the right hand.
My BMW handlebar mounted brake lever works both front and rear ABS brakes.
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Is the question in relation to motor or pedal cycles?
If the latter, the Americans do have their brakes the "wrong" way round.
Possibly something to do with Boston and tea and other colonial petulance I expect.....
Edited by Humph Backbridge on 07/01/2009 at 16:59
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... while cars don't have similar feature?
Well there's always the hand brake!
Mainly used back brake on the bike today. Even with a 5 teeth increase on the rear sprocket and only 60bhp it was still able to spin up in second gear.
Huge recommendation for Continental Escape tyres, cornering was a little slidy but not in a worrying way!
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On a bike it's easier to just use the rear brake for very slow speed riding, it's often safer to use a touch more rear brake if conditions are very slippery. The reason for this is it's easier to save a rear wheel slide (bit like yanking the handbrake on) than a front wheel slide (if the bars are turned even a little, you're on the floor before you know it)
When I were a lad some racing cars had adjustable front-rear brake bias via a double master cylinder so it's not unheard of on cars.
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Yup although if you come off the front quickly enough you can save it! Always a good idea to practice in a slippery field or something to get it into 'muscle memory'.
Or get a bike with A Big-girls-blouse System. ;-)
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"When I were a lad some racing cars had adjustable front-rear brake bias via a double master cylinder so it's not unheard of on cars."
Still have them! 'Biased Pedal Boxes'. Very useful on rally cars to get the backend stepping out to set the car up for a corner on loose surfaces.
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All mechanically propelled vehicles require (by law) two separate braking systems. Four plus wheelers have handbrakes, bikes have front and rear brakes. My BMW has linked brakes from the front lever (best brakes I've ever experienced on a bike - servo assisted with ABS) and the rear brake can be used on its own. The ABS can be switched off (for riding in the snow - oh yes as if)
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The reversed left-right brakes thing is certainly true on American pedal cycles. I have one I bought in Texas a while ago and I've never bothered to swap the cables over, although it would be easy enough to do. It was explained to me that having them this way round allows the rider to give a right-turn signal with one hand and apply the back brake safely with the other. Don't know if, say, French bikes have the same feature.
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Sounds quite sensible that - perhaps a little too sensible for this country.
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Sounds quite sensible that - perhaps a little too sensible for this country.
That's how we have it though isn't it?! Front brake is on the right so we can use the back while indicating right. If turning left it's not really is vital to signal.
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Most pedal cycles in countries that drive on the right have left/front and right/rear. Some manufacturers reverse this for bikes imported to the UK, most don't bother. It's awkward to swap them on a bike with hydraulic brakes as you need to bleed and re-fill the system. Simply swapping the levers doesn't work as you'd need to cut the grips off and then the levers would be upside down.
It's always worth a check when renting a bike from a trail centre to see which way round they are. Also worth checking (depending on the hire outfit) to see if they actually work at all.
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Braking percentages should be
50/50 in the wet
75 front 25 back in the dry
two levers help the rider to brake optimally
MVP
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>>Braking percentages should be
Where do those figures come from?
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I know many riders who rarely use front brakes on bicycles!
I usually use both brakes on bicycles.
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Look at this the other way - how would you work both brakes off one lever ?
Various manufacturers have tried linked braking systems on motorcycles with varying degrees of success. The BMW ABS / Servo assist system works well (I think the servo assist has now been dropped ?).
I think as ABS becomes more common - and more useful - on motorcycles, then we will see many more linked systems.
If full front brake is applied on a motorcycle at speed then the back wheel will typically lift clear of the ground - you need to release the back brake fully, so relative brake loads are very difficult to set for any mechanical system.
BTW - I thought racing motorcycles had reversed pattern gear shift (pedal down for upshift) so that the rider could still change up at high lean angles - downshifts typically happen braking into the corner, but an upshift may be required in the corner and the boot may not fit under the pedal.
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>>If full front brake is applied on a motorcycle at speed then the back wheel will typically lift clear of the ground
Yes, that's why I was asking about the provenance of the front / rear braking ratios above.
As motorcycles have both a high centre of gravity, and a short wheelbase, the weight transfer is a massive effect, and the static weight distribution has little to do with how brake force should be distributed during deceleration.
Incidentally, if you ignore the movement of the suspension for a moment**, weight transfer depends only upon the wheelbase and the height of the c of g - it doesn't matter if it's the front brake or the rear brake which is applying the braking load.
** There is a smaller, secondary effect whereby the sprung mass and rider move forward as the forks compress, and this secondary effect can vary depending upon whether the front or rear brake is used. This secondary effect happens on cars too, but is much diminished owing to the longer wheelbase, and different suspension geometry.
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My Honda FJS600 has an interesting brake system. The front brake works off the right hand lever as usual, but only works two of the three pistons in the caliper. As I have no clutch lever, the left hand lever works both the back caliper and the third piston in the front, but with a time delay. It also has a fly off handbrake under the glove box. I am told she can stop on a sixpence......whatever that is ! Nothing for the feet to do !
Ted
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>>If full front brake is applied on a motorcycle at speed then the back wheel will typically lift clear of the ground Yes that's why I was asking about the provenance of the front / rear braking ratios above. As motorcycles have both a high centre of gravity and a short wheelbase the weight transfer is a massive effect and the static weight distribution has little to do with how brake force should be distributed during deceleration.
I have always been told those percentages are a guide only.
Riding a motorcycle properly / safely is a highly skilled thing!
Id go as far as to say most 'bikers' do NOT possess all the skill required!
to control a motorcycle requires a lot of feel, and use of all the senses, including smell (diesel on road) taste can be a part as well alongside smell.
A skilled motorcyclist becomes part of the machine.. understands every movement, noise, feel of whats happening, and adjusts the inputs as and when needed - sometimes before most people would even realise... maybe a difference in grip.. that kind of thing.
get everything right... theres no better feeling!
get one thing wrong... theres a big possibility of never feeling anything again.............
BTW... i include myself in the 'most 'bikers' do NOT possess all the skill required!
in my youth i was lucky... now im older and steadier...
Edited by the swiss tony on 09/01/2009 at 05:50
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