Brakes and ABS

I had to first change the rear brake pads on my F800gs when I was green laning and the pads just worn out completely in less than 4 hours riding. I haven't had that problem with the EBC ones.. they may have been a softer, more abrasive set of pads though. The ones that came originally on the bike were Brembo pads which I would think can be purchased independently of the dealer at a fraction of the price?

That sounds truly appalling! Still, based on your experience I have just ordered a set of new pads for a longish trip I am making starting this week. I have used my bike a fair bit for greenlaning in both muddy and dusty conditions but according to the pad wear indiucator grooves, still have a decent amount left. However, don't want to be caught short!

I think I am getting paranoid, I have been dithering all week about getting the chain/sprockets replaced - based on people's experience here.
 
6500 miles and just took the wheels off the GS650 to change tyres. I was very surprised to see so little life left on both front and rear pads. Surprised at the mileage but double surprised they were not checked at the 6000 mile service. (Just as I expected, a quick oil and filter change + sod all else). Only a pillock would buy genuine replacement pads if 7000 all on road miles was all you can expect, Its Ferodo pads this time, approx £30 total for front and rear from Motoworks.
 
Dont think I mentioned before, almost every web site you visit for parts such as pads has a pull down menue for bike make and model, it seems the rest of the world cannot be bothered with BMWs silly name structure and totaly ignore the the F650GS as an 800 twin, cant say I blame them.
 
Ok - so I've done mine. Replaced the OE 'Brumbo's' with EBC standard pads. I dropped the front wheel out, the caliper pins were corroded into their holes and it was a little fiddly getting the shoulders of the pads back into their 'shoe' in the caliper, but I managed it. Job took 45 minutes start to finish - a genuine piece of p!ss...
However ... har har har - when I pumped up the brake to settle the pads, they were binding so badly it was quite difficult to turn the wheel by hand. I took it for a quick spin round the block to see if it would free off, but no it bloody didn't!

When I got back into the garage I gave myself a stern talking to and told myself that I should have RTFM !! Hindsight is wonderful isn't it? So, I RTFM and this time took the calipers off the forkleg .. hmmm yes, it was easier that way! I took the new pads out again, looked to see if I'd made any stupid mistakes, but no - it all looked ok. While the pads were out again I pumped the brake pistons out a bit - on both calipers one piston moved before the other but that didn't surprise me too much. It all looked clean enough, but I got a toothbrush and brushed a little brake fluid round the exposed piston to clean and lubricate it and did the same to the other piston. Both looked a little dry - probably irrelevant. I took the opportunity to clean the rest of the caliper up as well - took out the anti-rattle spring and cleaned all the crap out of the nooks and crannies of the caliper. Topped it all off with a smear of copper grease (I've used Halfords grease which is brilliant because it's almost solid and doesn't get everywhere like the cheap sh!t Comma grease I've also got...) over the brake pin, the 'shoes' in the caliper, the anti-rattle spring and the pad backs.

When I put it all back together for the second time the brakes were still binding, but not anywhere nearly as badly as they did before. I'm guessing that the high spots will bed-in and my brake performance will be back to normal...

Greg
 
F650GS with ABS

So the big day arrives, I am off to collect my 1200GS. I hop on my F650GS twin and head off to the dealership to pick up the beast. Half way there and I pull the brakes with plenty of room between me and the car ahead, ABS kicks in immediately on a flat smooth road, release the brake apply again, stop in time. For those of you with a twin take care, I am told this is due to the anti stoppy technology and one of the main reasons why I have ordered the beast.
“Let’s be safe for the last 10 miles” so I switch off the ABS at the next traffic light. Bad mistake, 5 miles later car pulls out in front of me in a traffic circle, grab the front brake and it slips out from under me and down I go. SOB drives off and I am lying in a pile with the bike on top of me in the middle of a traffic circle. Where’s my ABS now!
No serious damage to me, sprained ankle, torn ligaments and huge bruised ego. Spitting every profanity on the planet I get up pick up the bike and move to the side and check it over. £700 quid later and on the day it was to be traded in.
To cut a long story short I have a 1200GS, love it, less money and more respect for the road than ever before.
Moral of the story, any day could be your day just treat it that way but enjoy it! Oh yeah, and if you are on an F650GS with ABS take extra care.
Cool running’s!
 
Ah a wise man!

Yes we can certainly add that as well. And yes you slide and slide. But if you are on a Twin dont ignore what I am saying! take care!
 
Ok Guys, this is just a good story for those of you on a 1200GS, for those of you that don’t get it from a Twin perspective then this is the bit you need to watch out for.

"I pull the brakes with plenty of room between me and the car ahead, ABS kicks in immediately on a flat smooth road, release the brake apply again, stop in time. For those of you with a twin take care, I am told this is due to the anti stoppy technology"

Don’t ride to close to the car in front of you, particularly when its a little bumpy, the back wheel just needs to lift off the ground a little while breaking, the bike thinks that you are doing a stoppy, and the ABS system releases the breaks. BWM advises that when this happens you should release the break completely and reapply. When you are staring at the back of a white van, releasing the break is the last thing on your mind.
 
In 9000 miles so far I've only had the ABS kick in a couple of times, and then it was only on bumpy gravelly sections of road. Shouldn't rely on the ABS anyway, it doesn't make a vehicle idiot proof, only fool proof.
 
Ahem,

If the ABS kicks in - Don't ease off, keep squeezing the brakes hard.

Easing off tends to be a natural reaction for most riders - 'cos that's what we were taught to do when the tyres let go.
But if you ease off when the ABS kicks in - you are effectively fighting against it and increasing your stopping distance.:rob

(Edit) unless you're on gravel or a very slippy surface, but for normal road conditions just let the ABS do it's job.
 
Tim

Yes I released the brake completely and applied again from scratch. The reason why I refer to the twin in my mail is two fold

1) Its the F650GS Twin model and not the 1200GS, I have no experience of the ABS on the Single cylinder F650GS's and can’t comment on them.

2) Out of habit sadly, I am tiered of explaining to people that my 650 is actually a 800. Even pulled the stickers off the thing eventually.
 
That's normal behaviour with all ABS systems, cars as well as bikes, though bikes are more susceptible. When the vehicle goes over the bump with brakes engaged, the reduction in mass causes the brake to lock the wheel and the ABS system therefore does its cadence breaking.

There's a roundabout near me with yellow bands across the road beforehand and both my F650GS (twin) and my R1200GS (twin) can lock up then disengage if breaking sharply.
 
Tim
From my experience the delay is too long and is dangerous, F650 is sold as a “First Big Bike Option”, it takes balls for a newbie to let go and reapply in these circumstances. For the record if I were buying this bike again, I would probably go for the ABS again; it would have kept me upright on the second incident, so ABS is the right direction.
You need to understand its limitations and be prepared. If this is a problem that you have then I would take a look at suspension setup, it might be worth talking to BMW to help you get the right setup to minimise the wheel lifting. In addition I think Size, I am 110KG and your position on the bike(I sit well forward) all play a factor.
 
Who on earth advised you to let go and reapply? That's the last thing you should do. The whole point of ABS is to eliminate the need for people to do cadence breaking manually. The electronics will sort things out in milliseconds, far faster than you or I could hope to achieve.

One of the causes of crashes with ABS is people reducing the pressure on brake levers when they feel kickback through the system. :eek

From what you've wrote in your first post in this thread I don't think it was a 'stoppy', just a normal front wheel lockup. The wheelbase on the F650/800GS is particularly long (it's actually longer than the R1200GS) and this reduces the chance of both wheelies and stoppies.

Given that you had two 'events' in quick succession I would suggest a visit to your local advanced riding club (IAM or ROSPA). :augie

Tim
 
Don't forget BMW's advice, if you experience an Extended brake hold off (BMW are aware it happens and claim it's "by design"), is to release the brakes completely, and there by defeat the ABS operation, and re-apply them.
They make no mention of the consequences of this lost braking time or fact that it flies in the face of ABS operation (being to apply and hold your brakes on).

And for the record some advanced driver training is on the cards, you are never to old to learn.
 
Have a look in the Rider's Manual at the explanation of
- how the ABS system works,
- how it is affected by lower friction surfaces, and
- how it is affected by surface irregularities.

There's nothing in the manual about an extended brake hold off.
 
While the sensation of the ABS backing the brakes off when you have yanked them on full is somewhat frightening first time round, the ABS is simply doing it's job and preventing a skid. As soon as the ABS feels traction it will yank the brakes back on for you. For full effect experiment on a damp road in a straight line. Yank them on and hold them on. Or just try the rear brake as the ABS on that will kick in very quickly in the wet, but just make sure you are in a straight line when experimenting. You quickly get a feel for it and learn to trust the system. It does work.

Off road and on gravel, turn the ABS off as it never senses grip hence you effectively have no brakes which is entertaining!
 


Back
Top Bottom