Pinking and Vibration on 2017 2200 GSA

[gbags]

Hi all,

I’m in South America, riding a long way in tough conditions and my bike has developed a vibration and pinking.
Firstly, what’s the grown up name for pinking? I took it in to a good mechanic who only does Beemers and he ran a diagnostic on it. I’d tried to explain ‘pinking’ in Spanglish but he found nothing wrong. The pinking occurs when I wind the bike hard or load it up. I’m two up but this bike is made for this, surely? I got the guy to change the engine and transmission oil but it didn’t help.

The second problem is vibrations through my hands and feet. The vibrations and pinking seem to be getting worse. Are they part of the same problem?

I had the bike serviced by a proper BMW dealer about 8,000 km ago. Neither problem was there before that. I’m not connecting or blaming anything. I think they are developing because I’m riding a tough route.

Can anyone suggest a possible cause and cure please? I’m not mechanical but this bike is just not well and I have a long way still to go.

Many thanks,

Graham

[gbags]

1200 GSA

[Nigel]

Poor quality,low octane fuel?

[Flintlock]

If above and you don't have access to better fuel, would there be an additive you could purchase and add to the fuel when you fill up??

[herman]

https://en.wikipedia.org/wiki/Engine_knocking I would of thought it would of had a knock sensor etc but if the fuel is really bad then that is what you will get.

[OnHellas]

As above, low octane fuel plus altitude?

I found the fuel to be OK all the way through the America’s but you may have picked up some dodgy stuff I suppose.

Does it do it all the time?
Just when accelerating?

Next time the tank is nearly empty you could try draining what’s left and start afresh and add octane booster.

Which country are you in Graham? There appear to be quite a few BM dealers in Colombia if you’ve got that far north.

Let us know how it goes, good luck.

[catcitrus]

If its slowly getting worse I assume that you have been through at least one fill up. I'm not sure whether your bike has anti knock sensors which would automatically retard the ignition slightly when using poor quality (less knock resistant) fuel? However, pinking is essentially a pocket of mixture in the corner of the combustion chamber going bang due to heating and radiation from the flame front-and not burning as it should--hence the metallic knock---but very rare these days, especially with twin plugs starting the burn process from both sides. If something fundamental hasn't gone wrong with the timing (doubt it) I would start to look at the fuel filter/pump/injectors, and the air cleaner--fuel in particular--lack of proper fuel delivery will lead to a weak mixture which will cause slow burning, overheating, and pinking (pre-ignition or detonation).

[AlanHolt]

Pinking: pre-ignition. A weak mixture can increase cylinder burn temperature, if the cylinder gets too hot, the air/fuel mixture will ignite prematurely under compression before the spark plug arc, causing pinking. Continuing to ride like this can lead to valves burning out and pistons melting.

[AlanHolt]

As you say you also have a vibration, it could be that a plug is failing, causing the pinking and slight misfire. A new set of plugs will be the first and easiest option.

[Nigel]

If its slowly getting worse I assume that you have been through at least one fill up. I'm not sure whether your bike has anti knock sensors which would automatically retard the ignition slightly when using poor quality (less knock resistant) fuel? However, pinking is essentially a pocket of mixture in the corner of the combustion chamber going bang due to heating and radiation from the flame front-and not burning as it should--hence the metallic knock---but very rare these days, especially with twin plugs starting the burn process from both sides. If something fundamental hasn't gone wrong with the timing (doubt it) I would start to look at the fuel filter/pump/injectors, and the air cleaner--fuel in particular--lack of proper fuel delivery will lead to a weak mixture which will cause slow burning, overheating, and pinking (pre-ignition or detonation).

From what i have read the GS doesn't have a knock sensor, it is an option along with sub menu in ecu for low octane fuel, guy rode through Baja on low octane though with no problem apart from decreased mpg,
I'm wondering if it was contaminated fuel and as said before fuelfilter/pump blocked.