800gs ABS

[Xskydiver]

Why in the heck isn't the ABS switchable on the fly? For a bike designed to go from dirt to street and back it seems like it would make sense to be able to switch the ABS on and off while riding. Who wants to stop every time the riding surface changes? Around here you can transition many times over the course of a day's ride. This is probably my only complaint so far although I only have 300 miles on it so far.

[Boon Booni]

Having an ABS weestrom, I find that gravel and dirt are just fine with ABS on. Only time I really feel the need to switch it off is when the going gets sloppy.

[jeffchri]

Try just leaving it on regardless of surface. Works fine.

[M N B]

Originally Posted by jeffchri

Try just leaving it on regardless of surface. Works fine.

In rough terrain or anything twisty, you definitely want the ABS off. However, leaving the ABS on in some situations can be handy - like going slow down a steep hill with poor traction.

They don't have the technology to sync and shutdown the ABS on the fly. The F800GS has the most advanced system in this regard as you don't have to power down to shut it off. Just come to a complete stop.

[Boon Booni]

Originally Posted by M N B

In rough terrain or anything twisty, you definitely want the ABS off. However, leaving the ABS on in some situations can be handy - like going slow down a steep hill with poor traction.

They don't have the technology to sync and shutdown the ABS on the fly. The F800GS has the most advanced system in this regard as you don't have to power down to shut it off. Just come to a complete stop.

Weestrom must be more advanced, I just shut it off while moving. Can even turn it back on while moving too.

[Threewheelbonnie]

Former ABS design/test engineer (trucks) here. There is no reason an ABS can't detect a loose surface and switch modes (or turn off) without any rider input IF it's designed to do so.

What BMW are running scared of is lawyers. Imagine the fuse blows and the big red ABS FAILURE light comes on. Matey thinks "stuff it", rides on like a nutter and has a prang with a petrol tanker. The first thing he'll do is claim the ABS should have saved him, that there was no warning blah de blah, BMW should write a cheque etc. When this fails he'll claim he'd been off road and maybe forgot to reset it to road mode. BMW's lawyers will want to know where he stopped and will want to see the ECU. The ECU has no clock, but it does know the sequence of ignition switch, off road switch, failure and wheel speeds. If the sequence doesn't add up, matey boy gets the bill. The stop helps the lawyers say you knew full well the ABS was off, you didn't do it accidentally trying to turn the heated grips off.

The BMW system can in no way said to be "advanced" unless you are in marketing, have been living under a rock since the early 1990's and only talk to other people at BMW. The BMW system is possibly the most advanced one ever fitted to a production BMW F800GS, but that doesn't have the same ring to it!

Regarding ABS on gravel, it's pot luck. ABS assumes the best decel is achieved with a slip level you'll get on tarmac using the friction of the tyre on a smooth surface. That's the area the ABS searches in for the limit of adhesion. At some point depending on the particle size and what it is (gravel/snow/sand), a berm built up ahead of a wheel in deeper slip produces a higher decel. Smart systems detect they might be off road by looking at the wheel reactions under engine braking or between gears and stray into deep slip to see if that's better once they cycle. Systems that are less smart need you to switch them off when you decide how off road the off road is.

My advice: practice with both so you can spot a poor ABS surface before you use it in anger.

Andy

[]I)Money]

Originally Posted by jeffchri

Try just leaving it on regardless of surface. Works fine.

I strenuously disagree. a rough enough surface WILL equal zero rear brake with ABS on.

[Ike Baker]

Originally Posted by ]I)Money

I strenuously disagree. a rough enough surface WILL equal zero rear brake with ABS on.

Yep - I experienced this the first time I had mine out on a local ORV trail. Much pucker followed.

[Boon Booni]

Originally Posted by ]I)Money

I strenuously disagree. a rough enough surface WILL equal zero rear brake with ABS on.

With ABS you get to use a lot more front brake than you'd think possible.

But yes, if you're riding trails, it should be turned off. That said, I'm finding that as I get used to the system, and under stand how it works on gravel and dirt that it's not in the way as much as one would think. I used to turn it off every time I got onto gravel and dirt, now not so much.