Braking and ABS... I believe!

[dcarver]

ABS = good on street bikes.

ABS = good on dual sport bikes when ridden in the dirt.

ABS = bad on dual sport bikes ridden truly off road down steep hills with big gullies a the bottom.

 

[Fred W]

ABS = good on street bikes.ABS = good on dual sport bikes when ridden in the dirt.

ABS = bad on dual sport bikes ridden truly off road down steep hills with big gullies a the bottom.

Jeepers tend to be down on ABS for off road use as well. It has been blamed for some nasty accidents where people fell off mountains, etc. I know it's true cause I read it online.

 

[spalkin]

The FJR's front brake doesn't bite-in hard enough for me to lock it up.

It certainly will if there's something on the road that reduces the ideal traction. Which is the main point of having ABS. Anyone can come to a fast stop when running in a straight line on clean, dry roads. You don't need ABS for that.

Untrue. ABS can help on clean, dry road.

The rear brake is a different story. It's very hard to come to a panic stop without locking it up.

Try not pressing the rear brake pedal... Bet you won't lock the rear up then, and if you use a lot of front brake you will stop just as fast.

Great suggestion! Unbelievable. :clapping: No thanks, I think I'll add some rear brake.

Just coming to a normal stop you can notice how much the rear brake helps bring it down. If I could only get ABS on one wheel it would definitely be the rear. Then I could just stomp on it a hard as I wanted.

ABS isn't there for normal stops. But why would you want to stomp your rear brake in any stop? Or maybe you're just saying what I saidf in the prior post about not having to worry?

You never want to stomp on the rear brake. In the real world during a panic stop, it's easy to inadvertently lock the rear. ABS would control that and keep you straight.

I don't really mind if I kick the back end out in a hard stop, it's the damn flat spot from it.

Huh? :blink: No it's not. You don't wear a flat spot on your rear tire from braking. The reason you have a flat spot on your rear wheel is because you ride in (more or less) straight line and turn that thing on the right handlebar transmitting a multitude of torque through that rear tire to the ground. Guys that never touch their rear brake pedals still wear flat in the back.

Flat spot refers to the flat spot that can wear into a tire from locking it up, not the squaring off of the rear tire from normal straight line riding.

I'd like to hear more stories about how ABS saved the day. I wish I had it.

 

[fjr105]

I absolutely love the ABS on my 08, wont own another bike with out it, I've hit the brakes pretty hard a couple time and remained in total control, However I can see how a track bike would maybe only wont to go with ABS in the front only as well as off road bike's sometimes you need that lock up especially when you use the rear brake to help you turn the bike. $ .02

B)

 

[Old Michael]

I'd like to hear more stories about how ABS saved the day.

Well, ...............okay Spalkin. But just one.

Last spring on my first FJR. ( <<Long story.)

Long sweeping on-rampto the right, up over a rise, and then down as it dumps you onto the highway.

TWO lanes. Solid white down the center. Right lane is metered, 2 cars per green, stacked up, about 30 cars long, filling most of the ramps length, up and over.

Left lane is for carpoolers AND bikes, and sign says DO NOT STOP in this lane. Most Californians will be familiar with this scenario.

My left, "express" lane is completely clear, so I'm accelerating up the rise to merge with freeway traffic, AND being watchful for anyone even THINKING about pulling out of the right hand lane because they've just figured out they've got 2 people in the car, and they are in the wrong lane and they suck.

I'm up to about 50mph as I come up on the front of the line stopped at the light. And -----you guessed it. This car was about the 3rd one from the front, at a dead stop, and BANG! she cranks her wheel hard left(of course no signal) and yanks her car across the wide, freshly painted, solid white friggin' line, just as I'm coming up on her.

I had the front covered, and grabbed it probably too hard, while hustling my foot to the rear brake. I still would have hit her, had I not veered onto the debris covered left shoulder as I came up beside her. And there wasn't much shoulder, and a signpost right there, and I've almost emptied my bladder as I realize I'll probably survive this, and go on by her, thumbing my teenie, high-pitched, barely audible, stock horn, and of course gesturing back as I accelerate again to merge into speeding traffic.

I'm certain that without ABS, I'd have gone under her, over her, or through her back window. I'm certain I'd have locked up both, gone out of control, and had a really bad day. But neither wheel locked or skidded, and I maintained control of the bike, if not my bodily functions. I love ABS. Really.

Okay, going to take a ride out and look at the Pacific Ocean. Happy Saturday all.

 

[spalkin]

Awesome! :yahoo:

 

[Fred W]

The rear brake is a different story. It's very hard to come to a panic stop without locking it up.

Try not pressing the rear brake pedal... Bet you won't lock the rear up then, and if you use a lot of front brake you will stop just as fast.

Great suggestion! Unbelievable. :clapping: No thanks, I think I'll add some rear brake.

I am serious. I know that this is not what they teach in MSF, but think of the physics. If you are applying the maximum possible braking you will end up with 100% of the bike's weight transferred to the front wheel. Think stoppie here. With zero weight on the rear tire there is zero traction available so you get zero braking force.

OK, now that is an extreme example, and limited to a straight line on dry roads, but the concept is the same. If you are on a bike without ABS, in a panic situation you are far better off concentrating on getting the most out of your front brake than worrying about whether the rear brake is going to lock up. And if you do lock up the rear wheel and start to side slide, you will be losing some of the valuable effectiveness of the front brake.

I think we are in agreement as to ABS being a good thing and it adding to the stability in a panic stop. It just sounds to me like maybe you are expecting too much help out of your rear brake.

 

[spalkin]

Gotcha Fred, if you're up to the limits of adhesion on the front brake, the back would go so light as any rear brake would lock it.

I'm just thinking that the ideal would be to have as many wheels helping to haul it down as possible.

 

[eg23232]

The rear brake is a different story. It's very hard to come to a panic stop without locking it up.

Try not pressing the rear brake pedal... Bet you won't lock the rear up then, and if you use a lot of front brake you will stop just as fast.

Great suggestion! Unbelievable. :clapping: No thanks, I think I'll add some rear brake.

I am serious. I know that this is not what they teach in MSF, but think of the physics. If you are applying the maximum possible braking you will end up with 100% of the bike's weight transferred to the front wheel. Think stoppie here. With zero weight on the rear tire there is zero traction available so you get zero braking force.

OK, now that is an extreme example, and limited to a straight line on dry roads, but the concept is the same. If you are on a bike without ABS, in a panic situation you are far better off concentrating on getting the most out of your front brake than worrying about whether the rear brake is going to lock up. And if you do lock up the rear wheel and start to side slide, you will be losing some of the valuable effectiveness of the front brake.

I think we are in agreement as to ABS being a good thing and it adding to the stability in a panic stop. It just sounds to me like maybe you are expecting too much help out of your rear brake.

Anyone who thinks they shouldn't use the rear brake also, or that the rear brake isn't useful in threshold braking, then I suggest you do this exercise:

Set up a simple braking course. Measure out, say, 80 feet with a gate (couple of cones, another person standing to the side at 0). Enter the gate at 40 and threshold brake using only the front brake then check your braking distance. Do it again using only the rear brake then measure the braking distance. Then do it a third time using both brakes. You WILL stop in a shorter distance in threshold braking using both brakes.

By threshold braking, I mean braking just short of lock up and without engaging ABS.

 

[FJRBluesman]

Using both front and rear brakes is best IMHO.

 

[Fred W]

Anyone who thinks they shouldn't use the rear brake also, or that the rear brake isn't useful in threshold braking, then I suggest you do this exercise:
Set up a simple braking course. Measure out, say, 80 feet with a gate (couple of cones, another person standing to the side at 0). Enter the gate at 40 and threshold brake using only the front brake then check your braking distance. Do it again using only the rear brake then measure the braking distance. Then do it a third time using both brakes. You WILL stop in a shorter distance in threshold braking using both brakes.

By threshold braking, I mean braking just short of lock up and without engaging ABS.

First off, I never said the rear brake wasn't useful. It is under some circumstances. One such would be when the traction is reduced (due to water, sand, oil, etc.) so that full braking power cannot be applied to the front wheel without the wheel losing traction (or ABS engaging). In that case, less than 100% of the weight of the bike would be transferred to the front and the rear wheel can provide additional braking. Another situation is when doing any sort of turning in which case some percentage of the front tires traction is being used in the turning, making it impossible to apply full braking power to the front.

I think if you can stop faster with both brakes in your "threshold" braking experiment it's only because you did not really hit the fronts hard enough in the front-only experiment. With any kind of decent front tire the front wheel should never slip, so ABS should never engage, on a dry road, straight line braking. I would say that you should stop in the same distance in those two experiments if you are really fully grabbing the front brake.

But that doesn't mean that I don't use the rear brake.

 

[bandit]

Try that above exercise, Then try it again with your ABS fuse removed. You probally wont reinstall the fuse once you see how short you can stop without ABS on the same bike. Its a substantial difference. Now the rain is a bot different. ABS helps there.

 

[bandit]

Oh and those that dont belive the rear brakes serves a purpose under normal riding, I can only say , your wrong, Why would you only use part of your traction reserve by only using the front brake. Unless your doing a stoppie the rear tire has some braking power to add to any stop.

 

[mcatrophy]

I have a link to an ABS braking test, done under controlled and varying conditions using a number of riders with different backgrounds and experience.

For me it makes interesting reading, and may even help a rider make the most of his/her ABS system. ABS COMPARISON TESTS - No Fault Braking A Real-World Comparison of ABS Systems

 

[GAPS]

the rear end started fish tailing around ...... and the front end diving really unloads the rear end making it very light and easier to lock up.

You clearly understand what happened....and for a moment you rode like Jorge Lorenzo!

 

[palerider]

Try that above exercise, Then try it again with your ABS fuse removed. You probally wont reinstall the fuse once you see how short you can stop without ABS on the same bike. Its a substantial difference. Now the rain is a bot different. ABS helps there.

So should we leave the ABS fuse in only if we think it's going to rain?

I'm aware of stories about people who've been injured or killed because of seat belts and air bags, but on balance I think seat belts and air bags help more than they hurt. Same with ABS. On balance, more people will stop safely because of them.

 

[Fred W]

Try that above exercise, Then try it again with your ABS fuse removed. You probally wont reinstall the fuse once you see how short you can stop without ABS on the same bike. Its a substantial difference. Now the rain is a bot different. ABS helps there.

So should we leave the ABS fuse in only if we think it's going to rain?

I'm aware of stories about people who've been injured or killed because of seat belts and air bags, but on balance I think seat belts and air bags help more than they hurt. Same with ABS. On balance, more people will stop safely because of them.

I agree with you 100%. I love having ABS on my FJR. It was one of the reasons I chose the one I did (it was optional on 1st gens). But I also liked having ABS on my BMW R1100RS.

 

[palerider]

If you are applying the maximum possible braking you will end up with 100% of the bike's weight transferred to the front wheel. Think stoppie here. With zero weight on the rear tire there is zero traction available so you get zero braking force.
OK, now that is an extreme example, and limited to a straight line on dry roads, but the concept is the same. If you are on a bike without ABS, in a panic situation you are far better off concentrating on getting the most out of your front brake than worrying about whether the rear brake is going to lock up. And if you do lock up the rear wheel and start to side slide, you will be losing some of the valuable effectiveness of the front brake.

I think we are in agreement as to ABS being a good thing and it adding to the stability in a panic stop. It just sounds to me like maybe you are expecting too much help out of your rear brake.

But why argue extreme examples at all? Here's the thing for me: A millimeter can be the difference between a sharp piece of metal piercing my aorta or heart or eyeball. If I crash in the real world--which is where I tend to crash--and I can't get 100% of the bike's weight transferred to the front wheel (has it EVER happened in the real world that in a panic-stop someone got 100% of the bike's weight transferred to the front wheel?), then whatever added braking the rear adds can mean I stop that millimeter shorter. Way better to regularly practice panic stops and rear-brake usage and have that little (however little) shorter stopping distance than to forget about the rear brake and not practice and then for sure lock it up in a panic stop.

 

[Fred W]

If you are applying the maximum possible braking you will end up with 100% of the bike's weight transferred to the front wheel. Think stoppie here. With zero weight on the rear tire there is zero traction available so you get zero braking force.
OK, now that is an extreme example, and limited to a straight line on dry roads, but the concept is the same. If you are on a bike without ABS, in a panic situation you are far better off concentrating on getting the most out of your front brake than worrying about whether the rear brake is going to lock up. And if you do lock up the rear wheel and start to side slide, you will be losing some of the valuable effectiveness of the front brake.

I think we are in agreement as to ABS being a good thing and it adding to the stability in a panic stop. It just sounds to me like maybe you are expecting too much help out of your rear brake.

But why argue extreme examples at all? Here's the thing for me: A millimeter can be the difference between a sharp piece of metal piercing my aorta or heart or eyeball. If I crash in the real world--which is where I tend to crash--and I can't get 100% of the bike's weight transferred to the front wheel (has it EVER happened in the real world that in a panic-stop someone got 100% of the bike's weight transferred to the front wheel?), then whatever added braking the rear adds can mean I stop that millimeter shorter. Way better to regularly practice panic stops and rear-brake usage and have that little (however little) shorter stopping distance than to forget about the rear brake and not practice and then for sure lock it up in a panic stop.

Why argue extreme examples? Because they represent the extreme ends of the spectrum of possibilities.

Let me see if I can summarize this: If you have ABS then you can do whatever you want with your rear brake. It may or may not reduce your total stopping distance depending on road conditions. We are in 100% agreement here.

If you are riding a bike without ABS, using the rear brake aggressively in a panic stop situation is more likely to lock-up your rear wheel, increasing your overall braking distance, than to decrease it. Even after practice. Remember, you're in a panic. That's why they call it a "panic" stop. If your first instinct is to hit both brakes, you will lock the rear.

Yes, practice makes perfect. Again, I agree 100%. However, the people that are practicing what they think is maximum braking, are quite likely not grabbing all of the front brake available.

Edit - One more thing I forgot to address: Yes, it is quite easy to get 100% out of the front brake in a panic situation. If your first instinct is to grab that lever like nobodies business, and you trust that the tire will not slip, the adrenalin of the situation will allow you to get amazing braking going. Been there, done that, avoided t-boning the soccer Mom in the SUV that pulled across the road in front of me.

 

[jekirby]

The only reason I really never cared for ABS was the experience from my Beemer. I never used it and never knew what it was really like so to speak. Each bike is different on braking and yes, ~85% of braking is on the front brakes, so that would get the rear end felling light.
I will now be looking on my next bike purchase to make sure it has ABS. 10 years in ABS technology later really helps.

I had an '89 K100RSA and yes the abs worked, sort of. Sounded like little canons going off under the frame, very clunky. The computer was a real power hog and could kill a failing battery as fast as the head lights.