High speed pinging, 04 1150GS

[108822]

Hi,
I'm getting what seems to be major pinging in the motor when I accelerate from 75 - 80 MPH, in 6th gear.
I'm running the high octain but I have been getting fuel from Sams club. My current tank full is from the AAFES gas station and I'm going to try Exxon (and whoever they recently merged with) for a few tanks to see if it runs better.
Any other ideas? Maybe a timing issue? Is timing even adjustable on these things?
I might be making a trip to CT this fall on it and need to get this figured out by then.

Thanks, Al

[richc]

Al,

I've got an 'o4 1150GS and have not had any pinging. I use Chevron gas.

[DARKCLOUD]

Does the gas from Sam's club have alcohol in it? Sage advice from the rally in Trenton, "it clearly states in your owners manual not to use contaminated fuel". The pinging is caused by an increased compression ratio. Four ways to cure this problem, one, increase the octane rating in your fuel. Two, pull the heads and decarbonize. Three, run seafoam or Chevron Techron total fuel system cleaner in your bike. Four, run the bike up to 75, or 80 right before the pinging starts and keep it for a couple hours, then increase your speed another five mph. This method gets the heat into the engine and frees the carbon from the head. Load the bike down, and head into the wind, try to get six bars on the RID. RPM's, run at least 4,000 rpms, 5,000 rpm is better for the bike than 3500 rpm. JON

[fish]

Stock GS gearing is too tall to expect robust acceleration in 6th at 75mph. You should be in 5th.

[108822]

I'm not sure about the ethenol at Sams. It is usually identified pretty well at all the regular service stations. I've always avoided ethanol because when I tried it in one of my past vehicles, it would drop about 2 MPG.
I guess the carbon buildup could be a factor, I did baby it a bit for the first 1000 miles or so.
It is geared a bit high (especially 1st for an "enduro") but I hate to downshift just to accelerate on flat ground. I'll try it tomorrow on the way to work though.
Thanks for the advice. Hopefully I'll be able to run it at high speed for several hours next month. We'll see. I'm still optimistic about the change in gas, the whole octane thing is probably/hopefully my problem.

Al