Anti lock brakes... thoughts/opinions???

[wirelessguy]

I was curious if anyone out there has tried the TCB system brake kits?

http://www.tcbbrakesystems.com/index.html

In theory they sound like they may help make wheel lock up a tad more difficult. The cost seems pretty reasonable (for a part that likely cost them little to have manufactured) If it does the trick though, I think the expense would be pretty easily justified.

Anyone out there have an opinion if this is a waste of time or if it's worth researching further? Are there any other similar/better technologies you've heard of that could be retrofit onto a GS?

Thanks.

[Steve]

I like the concept of ABS. One of my sisters and her husband both have Wings with ABS and won't have anything else. He proved its worth in a panic stop to avoid a moose in Nova Scotia.

This system claims to be "a shock absorber for your brakes" and will "give you a feeling of more range in your brake levers" . To me, it sounds like they are intentionally introducing 'mushiness' into the system. In fact, that is what they are doing.

Here is a quote from the tech section:

The TCB introduces the give/compressibility factor to the brake system in the form of an accumulator. This type of accumulator uses a patented design that allows an air over hydraulic technique to dampen high levels of pressure spikes by tuning them into pressure waves. The compressibility factors introduced by the TCB are done by separating a pressure chamber and brake fluid with special elastomer/rubber diaphragm. This allows the dampening effect and gives your brake system the give/compressibility factor to occur without allowing air to mix with the brake fluid.

Basically, they are introducing an air bubble into the system, but keeping it sealed in a specific area so it does not mix with the brake fluid. There is something inherently WRONG with that concept.

Overall, they use a LOT of double-talk and useless, unrelated facts to present their story. It might be a bit more believable if there were fewer misspellings and grammatical errors.

One of their claims is that:

Electronic forms of anti-lock braking work only at certain speeds by quickly locking and releasing, but it needs to be emphasized that ABS still lets your wheels lock.

Yes, a wheel might lock for a milli-second or so, or it might just go enough slower than the other wheel to trigger the sytem to release the brake, but the fact remains that the wheel is not "locked up" long enough for the bike to lose control. They claim that their system

The TCB unit on the other hand works every time you brake and at any speed to help avoid the wheels from locking.

Well, duhh, they can't lock up because you are squeezing against an air bubble.


Yes, ABS is good, but this is not ABS.

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[bwringer]

The TCB brake mushy-izers are a well-known scam.

On a GS, the only available ABS is between your ears.

[bobthebiker88]

IMHO, adding ABS to a bike not originally equipped with, or offering it as an option is far more hassle, headache and financial strain than its worth. I'm not a huge fan of ABS, but to each his own. I likes my old technology and well, thats what I'm keeping.

[Steve]

IMHO, adding ABS to a bike not originally equipped with, or offering it as an option is far more hassle, headache and financial strain than its worth.

Most of the bikes that I have seen that have ABS as an option cost about $1000 more than the same model without. Imagine what all that hardware would cost if you were to try to buy it individually, then add in the hassle factor.

In the case of trying to add it to a bike that was never designed for it, it would be virtually impossible. Imagine trying to find and adapt wheels with speed sensors to a GS. Now try to find a place for the computer. Make sure the computer has a reliable power source. I think you get the picture.

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[wirelessguy]

All good comments and it does make me feel a bit more vindicated for my initial skepticism.

I'm not sure if I agree completely with the 'mushiness' description though. I don't think it's introducing the air bubble in a manner that I think would make you feel that so called mushiness in your hands. What it likely does is just keep you from being able to clamp shut on the brake at it pops itself open within a given interval.

What I don't like about that scenario is that there i no intelligence, so even if you're at a dead stop at a traffic light the TCB will momentarily 'slip' on the brakes and re-apply them.

Obviously the actual mechanics of a true ABS system are pretty complex but I did wonder why some company hasn't created some type of system that checks to see what gear you're in (say 2nd, 3rd or higher) and if you brake hard for more than a short interval (I'd measure 100 or 10ths of a sec) you could electronically release the braking pressure and re-apply. My thought would be to use the break lights since they are already indicating what you are are doing with your hand or foot. - Like I said, I guess it's way more complicated than that.

I do appr the good discussion though.
... and for now I suppose I have to continue using that gray matter between my ears.

[Steve]

I'm not sure if I agree completely with the 'mushiness' description though. I don't think it's introducing the air bubble in a manner that I think would make you feel that so called mushiness in your hands. ...

Take a good look at the picture.


In that little dome is a diaphragm with an air bubble above it. True, the air never touches the brake fluid, as mentioned in their advertising, but its effect is still there, every time you apply the brakes. You will have to squeeze the brakes enough to compress the air bubble until there is enough pressure to actually apply the brakes. TCB claims that this softens the application to prevent wheel lock-up. In that respect, they are absolutely correct. However, it is also likely to prevent proper brake application, too.

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[850GT_Rider]

1) True ABS does not degrade braking POWER. The brakes still have more than enough oomph to lock up the wheels. Through the use of rotation sensors, the ABS computer releases the brakes just enough to keep the wheels rotating, then re-applies the full pressure that you're putting on the pedal - same as pumping the brakes manually, just much faster pulses, and can be done on a wheel-by-wheel basis.

2) The primary reason that air is kept out of braking systems is because it's compressible, whereas fluids are not. The TCB system would seem to allow a certain amount of compression, i.e. same as a system that has not been fully bled of air! Because the air can compress, braking POWER has been reduced.

I, for one, won't believe the TCB concept is safe and effective until testing is done by independent labs......

[tkent02]

They sell these for RVs, my dad had one. It just makes the brakes less powerful, less sensitive. Not sure what the advantage would be, I didn't like it.
On bikes with old weak brakes like our GSes, it seems to be a bad idea.

[Steve]

Many of the guys here have upgraded to stainless brake lines to eliminate the little bit of mushiness from swelling rubber lines.

Why intentionally add even more mushiness with that little air capsule?

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[850GT_Rider]

Even their own website warns that you shouldn't depend on the units to NOT lock up the brakes. Every rider/motorcycle/tires/traction situation will be different.

Far better to learn (a) how to avoid the panic stop situations in the first place; (b) how to maneuver your way out as opposed to panic braking; and (c) when all else fails, how to use your brakes in combination with each other, to avoid skids or high-side exits.

[Turtleface]

Far better to learn (a) how to avoid the panic stop situations in the first place; (b) how to maneuver your way out as opposed to panic braking; and (c) when all else fails, how to use your brakes in combination with each other, to avoid skids or high-side exits.

I agree, with one caveat. I believe swerving should be your last option, rather than hard braking. If you try to brake before you swerve, you'll have lowered your forward momentum considerably, which would make the swerve far more likely to be successful. The best option is still #1, learn to recognize bad situations far before they materialize, and position yourself accordingly.

[wkmpt]

What about trying to pick up a wrecked (or just plain 'ol inexpensive) bike that has real ABS and fabricating a way to make it work? I think it'd be a first here on the forums (maybe?) and you'd make a veritable ton of fans.

I would think that there's enough bikes out there now that have ABS that it shouldn't be too hard to source one...

[Steve]

What about trying to pick up a wrecked (or just plain 'ol inexpensive) bike that has real ABS and fabricating a way to make it work? I ...

Not saying it would be impossible, but you would surely have your work cut out for you.

It's more than simply bolting on a couple of parts.

[GSJim69]

That is not good for this application. On aircraft the braking systems have accumulators. Their accumulators consist of a tube with a sliding piston in it. on one side of the piston is the hydraulic(brake) fluid. On the other side is nitrogen, pressurized to a specific amount. The nitrogen pressure is higher that the normal hydraulic system pressure. If the hydraulic pressure increases above the nitrogen pressure the piston will move compressing the nitrogen and lowering the hydraulic pressure back to its normal pressure. So, using an accumulator like this you could limit the pressure applied to your brakes preventing them from locking up. The nitrogen pressure is very critical. If it bleeds off any it would be like air in the system.
I would not trust a little diaphram like the one they sell. It might work fine when it is new. But, how long until it fails to work properly?
I do not experiment with my brake system.