Forum

[apparently lucky eddie]

A Roman road? Even the Romans built roads to get out of the place quicker! Reminds me of the old joke, "why are there poplar tree lined avenues in france? So the german army can march in the shade!"

[Adam]

Oh dear, Bryan. ‘Twas never my intention to shorten your life by posting the information regards the difference between stopping distances of motorcycles and trucks, only to substantiate jefrs comments about the matter. And it does make BLOODY TERRIFYING reading. I have no expectation of trucks stopping in as short a distance as a motorcycle but we all need to be aware of that fact, think about it… If a modern motorcycle travelling at 30 mph performs an efficient emergency stop it is likely that a fully laden truck travelling at the same speed less than 20 metres behind that motorcycle will flatten bike and rider, the difference in stopping distance is a serious road safety issue. Bringing 44 tonnes to a halt is a huge challenge for the boffins, that is why the likes of MAN, Mercedes Benz, Renault et tout are spending fortunes on developing more efficient braking systems, Volvo are even working with Cambridge University and have donated a tractor unit for experimental purposes. Before you ask, the heaviest thing I have driven on highway is a half loaded 7.5 tonner (100+ t gross off highway) but as a driving instructor (cars) I am reasonably aware of and certainly interested in any matters relating to road safety. Hope that clarifies where I was coming from with my previous post, Bryan, and I hope that you survived the night to ride another day, best, Adam. 

[Thack]

Personally I'm totally convinced of the benefits of ABS and am very pleased it is coming to REs. Of course it won't be coming to our Bullets or Contis until 2017, but that's OK - I won't be buying another until then.

[Thack]

Incidentally, ABS on motorcycles isn't as effective as ABS on cars when cornering. I'd like to see a re-run of that video with the bike banked over. I wouldn't be surprised to see it slide up the road.

[jefrs]

You will appreciate, especially the car instructors here, that in a modern car (ABS) you can stand on the brakes and it will stop, they're pretty much idiot proof. It may not be pointing the right way and it may hit something in the process but it will stop in the shortest possible distance and you will (probably) walk away. In RAF parlance, any landing you can walk away from is a good landing. Now with a lorry (I'm a bit old fashioned) there's a lot of difference between a 7.5 tonne van and a fully loaded 14 tonne lorry nevermind an artic. In town traffic a lorry can stop quick but at motorway speed (60mph) they really need written notice of stopping, especially if it's wet. It's about friction between tyres and road, the mass and the speed, not so much the brakes. The brakes are pretty good, they'll stop it as quick as they can.



You will also appreciate that with a motorcycle ABS will prevent the wheels from locking and causing a skid (an uncontrolled slide) but also when stopping in a hurry it is rather important not to fall off - and this is my sole objection to the linked brake (not ABS) -

That if the foot pedal applies the front brake when correcting a slide, you can be off. If the linked brakes use ABS it may release the front brake in time however we use this system all the time in cars, even with traction control, and I can assure you that it will lock a wheel before it releases it, and in the time it takes to release that front wheel, on a bike you would be off. ABS and linked brakes are very good on a car, you can feel it locking and releasing brakes under duress. The thing with cars through is they don't fall over when you do that.



Most of the time I really do think Nanny has gone mad.

[John M]

There is quite a lot of clap-trap on here regarding ABS The benefit of ABS is that a vehicle’s braking system has the greatest retarding effect just before the wheels lock, not when it is skidding. Skidding is a particularly bad thing as once a wheel is locked it will have no steering effect what so ever. Because a locked / skidding wheel has less traction than a rotating wheel a rear wheel skid will cause the rear end to step out and try and overtake the front. It is quite easy to lock a bike's rear wheel under heavy braking as weight is thrown forward. That is why cars have had rear brake limiters since 1980 and why a seized load sensing valve on a goods vehicle will result in an MOT fail. Anyone who is in the habit of braking heavily on a bend is already on borrowed time and probably needs the assistance of ABS and the Nanny State. If either of a bike’s wheels locks on a bend the wheel will slide out and the only way to recover the situation is to release the brake immediately to allow the wheel to start rotating and regain traction. In an emergency braking situation it is very difficult to release a brake when your brain is screaming STOP! In pre-ABS days this theory was demonstrated in cars (on a skid pan) by skidding and putting the steering on full lock. In this situation the car continued to skid in a straight line until the brakes were released where upon the car steered in the direction that the wheels faced. A technique called cadence braking was taught which was a manual application of ABS principals and the skidding demonstration was designed to convince the doubting Thomas’s. ABS ensures that a vehicle’s brakes operate at their most effective during emergency braking and by preventing the wheels from skidding steering control is also retained. The only time ABS may be less effective is on freshly fallen snow, where a wedge of snow forms in front of a locked wheel, not really a 2 wheel issue. I don’t like the extra complication and expense of ABS on bikes, but it works and it will save lives.

[papasmurf]

I am a bit concerned about people mentioning using brakes on a motorcycle in a corner.
That is a quick way to end up in hospital.
A small amount of rear brake perhaps, but both brakes???????
The other reason I am against linked brakes is on the rare times on is going down hill on wet grass or mud, any application of the front brake usually ends in a catsarsetrophy.
The other situation is a tank slapper where a slight application of rear brake can stop it.

[ric]

RE already produce a 500 with a rear disc as standard. It's an easy job to fit the latest rear end currently utilised on the home market Thunderbird to any other model currently in production so that it's shipped out with discs front and rear. Then it only needs ABS added to comply where required...

Personally I see the future emission targets posing a greater threat to the current models than anything else.

[Presto]

If you can’t use a brake, front and/or rear, with sufficient sensitivity (feathering or cadence) then I’m not sure you should be on a motorbike at all!

[Presto]

I mean when cornering!