Got a nice CBR1000F that I've had for a while. No issues, 25000 miles (40k) on the clock. Fantastic tourer, great fun on track days.
But now it's acting strange
Was coming back from christchurch and noticed it wouldn't rev to the redline.
And it's gone downhill fast from there, within a week of little riding doesn't like to rev past 7-8000 but will rev out further to the redline in a couple of seconds (in neutral).
In gear it is like hitting a rev limiter, feels grunty down low like it should but then hits a wall. As in it won't go past the new rev limit while in gear, only in neutral.
Thanks for all your suggestions and help!
Still not fixed but it revs out slightly quicker to the red line - will go to the red line in 1st while driving, just very slowly in the 8-10k flat spot. (in neutral it is fairly quick but has much less pickup)
While in the flat spot it sounds like a bike running out of fuel, but then when it hits 10krpm or so it can take off which seems counterintuitive to me if it was running out of fuel in the float bowls?
Seems to go now, either my last ditch effort extreme carb cleanout worked or what is more likely it was a dirty electrical connector I missed earlier. (the connector between the ignition coils and the main wiring loom). Thanks again for all your help
Summary of what I've done so far:
*** Cleaned carb with compressed air (and brakekleen and CRC clean-r-carb), thoroughly.
*Cleaned carb float bowl out, removed and checked jets (everything was very clean)
*Carb Vaccuum Diapgrahm
**Removed diaphragms, tried various things (CRC, autosol, sucking clean-r-carb through the vacuum holes which seem to have plenty of vacuum)
**Diaphragms seem to go up and down as you'd expect, can't find rips or tears anywhere i.e. they don't drop down instantly and they do go up under load
**after spraying CRC in the top of the vacuum diaphragm the bike ran perfectly (once) through the rev range which is the only time it has since the problem occurred.
*Removed air filter and reinstalled with sealant (runs worse without air filter, no difference noticed with sealant) Air filter looks fine.
*Drove bike with the choke on, runs marginally better (not a huge difference)
*Ran carbs through a funnel bypassing the fuel tank (can't see a filter anywhere unless it's built into the fuel tap)
*Drove bike with the fuel cap open (to check breather)
*** Found connector from ignition coils was a little dirty. Seems to have fixed it.
* Checked pulse generator and ECU output with oscilloscope.
*Replaced spark plugs which looked fine before I replaced them (light brown coating on porcelain/tip with black ring)
*Tried spark plugs out with bike running at idle (nice strong sparks, nothing intermittent)
*Checked coil resistances and timing unit resistanced (all within spec)
*Checked connectors around the bike (found one corroded terminal on the ECU that only goes to the tacho presumably to indicate RPM)
*Disconnected one ignition coil temporarily (bike just runs half as quickly through the flat spot)
*Found the regulator. It tests ok with the diode check on my multimeter (I am not 100% sure how to test it), but looks dodgy. Cleaned the connector block.
*Noticed valve timing was correct when doing tappet clearances.