hesitation at full throttle

[Crusher]

My 2006 R1150R has a hesitation when I open the throttle wide open at high RPMs. I bought it used this March with 71000 kms on it, and it runs great except when I am in a hurry and open the throttle WFO while going up through the gears. There is a definite hesitation at high RPMS with my right hand cranked. If I accelerate at moderate to brisk pace (IE half to three quarters throttle) the response is smooth as expected. Just wondering if anyone has any ideas what may be causing this. Any advice greatly appreciated.

[shake1150]

hi there,
I have a 2006 R1150R as well (with overdrive 6th gear). just wondering if your bike has the overdrive 6th gear as well? or just the regular 6th gear?
mine accelerates differently in 6th because of the lower gearing. but I wouldn't say it "hesitates". does the engine stutter? is that what you mean by hesitation?

these bikes like soft hands I find!

[Crusher]

Thanks for the reply.
Not sure what 6th gear it has, but it's not just sixth gear that it happens in. It's like it gets to around 5-6 thousand rpm then it just stops accelerating for a second then picks up again. Almost like it's starved for fuel briefly. As I said, if I use "normal" acceleration it is smooth as silk. Just wonder if it's a common thing or if something is wrong somewhere.

[johngellis]

I occasionally had similar symptoms particularly when the tank was less then half full. It also ran rougher than I thought it should but this was the first BMW I had owned I wasn't sure how it should be.

I bought the bike from a BMW dealer and he said he had replaced the fuel pump, so it was a year before I got round to checking the filters. (I changed and tried a bunch of other things)

When I took the pump off I found it had been incorrectly installed. The pump should be vertical, but was incorrectly positioned by 60 degrees. (its on a plate with 6 bolts). One of the external bolt threads had been stripped (it was held with 5 nuts) and the beather pipes inside the tank were leaking.

At this point I made a vow never to take it to a dealership.

If I was you I would buy new filters, gaskets and clip kit from Beemer Boneyard. If you really want to be sure buy a new fuel pump as well. Check all is well within the tank.

Once you have done this you can worry about balancing/setting the fuel injectors. If everything is set up right it should pull smoothly from 1600 rpm.

John

[riceburner]

these bikes like soft hands I find!

I'd disagree - my Rockster responds very well to a good thrashing!

[ROXTR]

Ditto on the above. I frequent the rev limiter and am rarely below 4k rpm. Zero carbon buildup on the pistons and runs like a clock.

[Crusher]

Thanks for the reply, Johngellis. Those are some things I can check at least. It sure feels like a fuel starvation issue, or air inleakage.