Motorcycle and Scooter appreciation

Been on the phone to BMW this morning and you can’t fault their service.

They’re picking up the bike tomorrow. They’ll try to fix at home but then, if they can’t, they’ll take it to my preferred Motorrad location for parts / a fix.

Don’t know another bike manufacturer with the same level of support.

Maybe they need it if their bikes break more often!?

Jesus fuck that sounds horrific. Glad you’re good. Something to be said about your skill kicking ass.
Had a similar thing on the first bike I bought coming off the slip road and double down shifting by mistake. Tyre slipped then caught traction again.

Is it a complete abs unit failure? Those kinda scared me on the older bikes when I was looking at the GS. Looked so bloody complicated.

Is it a complete abs unit failure

I'll find out tomorrow. If I have time, I might drive it round the block today for a quick test.

Real human skills will always beat over-complicated rider aids. When said rider aids fail, the point is proven. A lesser rider would likely have come a cropper. Well done for saving it!

Don't disagree but the problem was the sudden failure of a system I relied on.

If it wasn't there, I might have changed the way I approached the bend entirely.

I guess, moving forwards, I won't be so sure about the bike which really sucks.

My bike instructor had his rear brake calliper come off and go into his spokes on his ~2017 GS at 70mph on the 3rd lane of the M4. Common fault apparently but BMW didn’t recognise it as such and tried to squirm out of repairing/replacing.
Think it was written off in the end. Although he was just glad to be alive

Frightening experience and completely understandable that you will have to find your level of confidence in the bike once you start riding again. Well done for saving it.

There's probably not much option in new bikes to avoid these types of rider aids and lets face it older bikes have their issues too. Thankfully you live to tell the tale.

Based on what you were saying the bike was adjusting for the amount of brake input to avoid locking the rear and when the system failed it locked the rear instantly. Am I arriving at the right conclusion?

FWIW I think BMW have been trading on their engineering reputation and their modern bikes have had all sorts of issues. The RT's a few years back had exploding rear shocks and the series before that had issues with the shaft drive, even the earlier 1150rs has a low speed fuelling issue caused by there being only one oxygen sensor.

Ouch. I guess that you can only hope to regain trust in the vehicle.

The service department should do everything to get you riding again - they certainly don’t want you to provide hospital bills (or worse) because of a faulty vehicle nearly killing you. That is pretty much the bare bones of it. Good luck.

Based on what you were saying the bike was adjusting for the amount of brake input to avoid locking the rear and when the system failed it locked the rear instantly. Am I arriving at the right conclusion?

No, the traction control completely failed both on original corner entry and on subsequent input adjustment to modulate the power to the rear wheel, causing megaskidz both on the bike and in my trousers.

German engineer friend asked if you have diagnostics equipment to access the OBDLL events reader. He’s interested what the eventlist codes were leading up to and during the failure.

Think the beemer technician will let you photograph it?

Think the beemer technician will let you photograph it?

No harm in asking when he's here tomorrow...

Thanks

How much difference does it make to throttle control in terms input? If that makes any sense, as in how much electronic input is there?

I guess that depends on the bike / system.

For the Tracer 900, it completely cut throttle input on rear wheel traction issues when upright and limited throttle input at an angle. This was controllable at three levels.

~~Whilst less controllable, I believe the BMW system does the same thing. ~~

From the manual:

Traction control is available in two versions:

• without provision for the bank angle: Automatic Stability Control ASC. ASC is a rudimentary function intended to prevent falls.
  
• with provision for bank angle: Dynamic Traction Control DTC. DTC regulation is more delicate and more comfortable thanks to the additional bank angle and acceleration information.
  
  

Traction control compares the front and rear wheel circumferential velocities. The differential is used to compute slip as a measure of the reserves of stability available at the rear wheel. If slip exceeds a certain limit, the engine management system intervenes and adapts engine torque accordingly. BMW Motorrad ASC/DTC is designed as an assistant system
for the rider and for use on public roads. The extent to which the rider affects ASC/DTC control can be considerable (weight shifts when cornering, items of luggage loose on the motorcycle), especially when the style of riding takes rider and machine close to the limits imposed by physics.

Interesting. Does the GS have a lean IMU as well?

See above edit ^

Also:

Driving stability

1. In the DTC setting for RAIN, DTC intervenes early enough to achieve maximum driving stability.
   
2. In the DTC setting for ROAD, DTC intervenes later than in the RAIN riding mode. This prevents the rear wheel from spinning whenever possible.
   
3. In the DTC settings for RAIN and ROAD, the front wheel is prevented from lifting.
   
4. In the DTC setting for DYNAMIC, DTC intervenes later than in the DTC setting for ROAD, meaning that the motorcycle may drift slightly when coming out of the corner or do short wheelies.
   
5. In the DTC setting for ENDURO, DTC intervenes even later and is set to off-road mode so that longer drifts and short wheelies are possible when exiting corners.
   
6. In the DTC setting for ENDURO PRO, DTC control assumes that studded tyres are used when off road. The front wheel lift-off detection is switched off, so that wheelies of any length and angle are possible. In extreme cases, the vehicle can rollover backwards!
   
   

The bike was in ROAD mode.

https://www.instagram.com/p/CFsP24DJsrQ

So it was basically 100% that but I saved it at the end, and it lasted about twice as long.

When it came up on insta I wondered if you had that exact buckaroo minus the off.

Currently struggling to find road-oriented tyres in 21 & 18 rim size, for the second wheel-set I should be picking up on Friday.

Don’t want to go too far astray from the oem 80/100-21 (51P) 110/90-18 (61P), but even the Trackers the mechanics ordered me were 120/90-18 (65R) due to lack of options.

The road-ish tyres they also considered ordering me were Sirac’s, so I’m assuming they were going to run me a 90/90-21, as that’s the nearest I can see online.

https://www.tacomaworld.com/tirecalc?tires=90-90r21-80-100r21

Ok, mental. I guess you can end up not really knowing how much the bike is doing to sort stuff out. It seems like a good thing to have on paper but I'm not sure I'd want to trust it. I guess you can switch to a setting that gives you a little bit more feel for where the natural limits are. Dynamic sounds like a good setting. I love going sideways with the front wheel off the ground :)

BMW tech guy showed up first thing this morning...

Rear-wheel angle sensor fault (which meant it didn't fire off the traction control).

Probable cause: the install of the cansmart controller for the LED spotlights.

Not my picture but the bit in the middle of the under-seat area; with two bolts sticking up from it, is the DTC wheel angle sensor:

Apparently, nothing should touch the sensor, or the wires coming from it. Unfortunately, they've placed it directly under the rear seat, with no protection or warning labels, in the only place anything luggage wise or modding etc can be installed.

So now the cansmart controller is wrapped in an old sponge and cable-tied out of the way.

Fingers crossed.

@Soul - shit the bed mate, glad to hear you're ok. Has it affected your confidence on the bike?

I haven't been on it since but that's because I've been flat out with work.

Got Friday off and the weekend to maybe get out for a ride so we'll see!

So is that what caused the initial lock-up?!
Had a slight poo-pants moment this morning as my rear tyre slipped about 3cm sideways on wet road letters, fairly confident in the bike though after sliding significantly more sideways on a gravelled corner at 10mph!

Yup.

Apparently, if anything touches it or knocks it during riding, it can fault and completely fail to report anything. This means the engine doesn't manage torque and you have a 250Kg machine trying to deliver all 143Nm of torque to the rear wheel even though you're sideways.