R1150 GSA FUEL CONSUMPTION

[robmack]

Just got back from a trip to Germany and noticed a huge increase in fuel used.
Was travelling with Whatton who although does not have the adventure gear box managed to use 7 litres of fuel less than me in one fill up, scary eh?
My bike seems fine starts and runs no problem and accelerates well.
Problem seems to be in 6th gear the bike seems a little sluggish and is slow to respond.
The bike pulls hard in 5th and will accelerate to 110 mph no problem (on the autobahn of course ) i have checked the plugs which all seem normal, twin spark and have balanced the throttle bodies which seem fine, i have also removed and cleaned the brass screws.
Throttle cables are also seated properly.
Whatton has a large fuel tank the same as mine and was using the same H&B boxes.
Would be grateful for your advice guys.
Rab

 

[ianboydsnr]

if a coil cap is breaking down, you will use more fuel as you will use more throttle for the same performance

 

[Deleted account W]

if a coil cap is breaking down, you will use more fuel as you will use more throttle for the same performance

That was one of our suggestions at the time

 

[Fanum]

Same tyres?
(TKC's increase fuel consumption)

Same screen/angle?

Riding style? (Did you pull away faster than he did?)


I was going to ask if you're a large chap but FFS this is a comparison with....er......no, I'll leave that there


I assume you both brimmed it on the previous fill up and then he used the 7 litres less on the next brim up?

On my Adv I can fit in 4 litres more if I fill slowly and carefully from the point where it looks brimmed, due to the neck drilling

Also a lot would depend on the 'zorst flow....with a remus on, my fuel consumption shot up....what did you both have on?

 

[Stumpy]

Whattons panniers are full of these

 

[robmack]

Looking at a previous post by Den it's looking like the coil pack/stick coil is the likelyest culprit.

 

[clivewhilde]

I had a similar problem in Germany in 2005. Bike started well but coming home I noticed less MPG and less performance. I had accidentaly filled up with low octane fuel, there seems to be three octane levels in Germany 98, 95 and a crappy 92/93 (can't remember exactly). Anyway the bike didn't like it and despite filling up with better fuel it didn't go back to normal. The bike went in for a service when I came home and I rode out on a K1200R so I don't know how BMW fixed it but they said they would reset the engine mangement system, maybe it had gone in to safe mode or something.
Could you have filled up with low octane? Did you keep your fuel receipts??

 

[Aussie]

6th gear is lower on the GSA than the GS, if you run above 4000 rpm you will use a lot more fuel, the joy of 54 mm throttle bodies

 

[davegs]

consumption

6th gear is lower on the GSA than the GS, if you run above 4000 rpm you will use a lot more fuel, the joy of 54 mm throttle bodies

This would be with the endro gearbox an option over here.

 

[Hong Kong Nick]

With a recent stick coil problem solved, I can attest to the crap fuel consumption associated with this problem. However, from my experience, the failing coil manifested itself quite quickly, with crap fuel consumption, 'breathlessness', surging, hesitation and massive backfiring all coming about pretty much at the same time - my point being that fuel consumption issues alone weren't the only indicator of a failing stick coil, at least not so in my case.

2 new ones certainly made a difference to everything, though.

Good luck.

Nick

 

[Pukmeister]

Running rich for some reason? Fuel injection system reacting a bit too much to a given throttle input? Badly fouled air filter? Crap stuck in the intake snorkel?

I know you said the spark plugs look fine visually, but we are talking about use over a full tanks worth of fuel so even a tiny bit more fuel injected per rev makes a noticeable difference overall. Seven litres difference is a helluva lot though, almost 2 gallons.

Know anybody local to you with a rolling road dyno that could do a quick 'power run' and measure your air/fuel ratio? (assuming no ignition/induction faults).

It'll be interesting to discover the cause !

 

[Jon]

This would be with the endro gearbox an option over here.

AFAIR the 6th gear was always a "6th gear" on the GSA rather than "E" overdrive or whatever it was called that the std GS had. The only option as such was the lowered 1st which was called the "enduro" gearbox option.

All that being said, if I'm giving it large with my GSA, particularly on a fast 100mph+ motorway run (where it's legal, or course ) the mpg plummets.

 

[Betty Swollocks]

Consumption

Just a thought.... dont suppose the KTM rider was about.... he mighta been thieving yer fuel for the crap range on his clown bike

 

[robmack]

Should have posted a reply to this sooner sorry guys, the problem was traced to a stick coil.
Definately was'nt the KTM rider Stevie ah watch the bugger like a hawk
Cheers Rab