RPM/Engine Pause....where's the juice!!!

[twindave]

Recently, my r1150r seems to cut out at around 6900 - 7000 RPM. I can't get it to redline. The engine doesn't stop running. It kind of hangs there at 7000 RPM for a moment, and then the RMP needle slowly drops down. It justs seems to run out of juice, and I have to shift to keep it going.

Any ideas why this may be happening?

[CycleRob]

How many miles on the bike and the fuel filter?

[twindave]

9900 miles on the bike
changed fuel filter spring (2008)
changed plugs spring (2008)

[CycleRob]

Since the tank was off this past spring . . . . Make sure the fuel QD's are completely plugged together. Same for the fuel pump electrical connector and battery terminal connections.

Also possible is a fuel line or filter leak inside the tank. A fuel pressure test will rule that out without taking it apart again.

Really out there is a fuse with an internal crack or separation. Replace the relevant fuses -or- remove/examine/test them using a horn or high beam headlite in a makeshift test circuit. I'd also interchange the 4 identical rectangular relays forward of the fuses. Switch the adjacent left 2 (load relief & horn) with the adjacent right 2 (fuel pump & Motronic). Do one change at a time so you'll know what went wrong.

.

[boxermania]

What is interesting is, assuming the engine pulls strong to 7K rpm and then dogs, just about 1K rpm away from the electronic cutout.....it appears the problem might be at the ECU, missreading the rpm signal. Nevertheless, check the intake air horn and air filter.

[twindave]

ok....

I checked the fuel lines and connectors..... No leaks.
I checked the fuel filter.... No leaks.
cleaned the K&N and air box/snorkle.
replaced the plugs..just in case...they're cheap.
Plug wires are new (few months old).
checked the synch with a twinmax. All OK.
replaced all the fuses with new ones.
checked the relays.... All good
Ran a tank of fuel with seafoam.

Still cuts out around 6900 RPM. Other than that it runs great!


Thanks for your help

[Eddiem]

Hummmmm....could this be a hall sensor either going bad??? I would check that.....

My 5 cents.

EM

[MikeCam]

Possible the new plug wires are improperly installed -- loose connection, underrated coil, etc.

Are they OEM? Aftermarket? Service installed or DITY installed?

Might be worth a check of that entire circuit.

[boxermania]

The mere fact that, according to the owner, the bike pulls clean to 6900 and cuts out tells me that there isn't any problem with the systems that support the fuel or the ignition. So it goes back to:

The ECM is cutting out early (doubtfull) or better yet I wonder if the Tach is reading correctly. One way to check it is to travel at a steady 70 mph and the tach should read around 3500 rpm. Of course if you don't have the overdrive it should read 4000 rpm. In either case if the Tach is the problem it should read lower rpms than the two shown above.....never seen a Tach issue.

[twindave]

Could it be the Techlusion 1031?

Staintune mid-box with a stock can. K&N air cleaner. Techlusion 1031 (open loop system - O2 sensor removed).

Techlusion pot settings are G - 3 1/2,,,,, Y - 3 1/2,,,,,, R - 5,,,,, RPM - 11

Anyone else have a similar set up? What are your pot settings?

Thanks!

[R4R&R]

Hummmmm....could this be a hall sensor either going bad??? I would check that.....

My 5 cents.

EM

That's my guess too.

5 cents more, so this is worth 10 cents now.

[twindave]

well...I just went for a ride and it tachs correctly. 3500 RPM @ 70 MPH.

Hal sensor eh? hummmm. Would that be the case with under 10,000 miles on the bike?

How can I check it to be sure?

[boxermania]

OK twindave....something else to keep you occupied. Excellent write-up/pictorial and source for inexpensive replacements.

http://advwisdom.hogranch.com/Wisdom/oi ... ensors.pdf

Remember read and plan twice, work once. Good luck and keep us posted.