[miller4254]

ok here is my issue, I just recently bought a 07' cbr1000rr and have put about 1k miles on it. so right now im at just over 10k miles. When i first took the bike out it ran perfectly. Acceleration and handling was a dream. I have done general upkeep. making sure tire pressure, oil/fluid levels, etc are all good before going out. Just recently I began having issues while at higher speeds. once I am in 6th gear approx 8k RPM (~120 MPH) the bike stops accelerating. not like its hitting a rev limiter and bouncing more like a speed limiter where in it just holds 8k rpm 120 mph and just cruises. I thought I might have a bent/kinked fuel or vent line so i checked them. no problems. took the bike back out and it accelerated to 145 mph no problem. slowed down for a quarter mile then began to accelerate again. ONCE AGAIN it stopped at 8-9k RPM 120 mph and wouldnt go any further. any ideas??? here is what I have done to the bike. Full two brothers exhaust, K&N air filter, Power Commander III, speedohealer, HID headlight kit, LED strips around the inside of the frame. PLEASE HELP!!!

 

[BurtonF166]

Unplug your power commander and try again.

 

[miller4254]

***UPDATE*** I took the bike out and it limits at approx 8k RPM in ALL gears. great response and accelerates like a bad bitch until that point then just settles. I will try unplugging the power commander and see what happens. thanks for the reply.

 

[nyknick1015]

well also try to re upload a map to your power commander as well... i had an issue with that before with my PC3, my bike ran fine but i had flat spots in higher rpms. it had a bad map that all the values were there up to 8k, anything higher it just read "E" (error) in all other values. Once i reuploaded a new map, night and day difference. chances are, thats what it is

 

[miller4254]

****final update**** After completely tearing apart the top end of the bike and checking EVERYTHING I found the issue causeing me to flatline at 8k rpm in every gear. On the bottom of the fuel tank the 17mm bolt that is hollowed out connecting the main fuel line to the gas tank was not lining up properly. In theory when this bolt is torqued to factory specs (16 ft lbs) the hollowed portion of this bolt should line up perfectly with the fuel line. After acting on a hunch I found out that at 16 ft lbs (for me anyways) the bolt was not properly lining up with the fuel line. To ensure that it lined up as it should I made a mark with a permanent marker on the bolt head where the hole in the bolt shank was then tq'd the bolt to factory specs. it was just shy of where it needed to be. so with my calibrated elbow I tq'd the bolt to line up with the fuel line. while I was tearing into the bike I also updated the firmware and re-uploaded the map for my power commander then put her back together. Took the blade out for a test run this morning and she ran perfectly. ***note*** for those of you who have the power commander III usb I highly recommend updating your firmware and downloading the add-on if you havent off the power commander website. Its called an accelerator pump. It gives you a little more control and tweak options to tune your bike to how you ride. I could definitely feel a difference in snap and response when I took her out this morning. Thank you all for your input and suggestions. hopefully this thread will help others find the solution to their own "demons" a little quicker than it took me. 3 days off the road was a little too much for me. :/

 

[MattCBR]

wow thanks for the update... I'm going to be changing out tanks on my bike... that's a good tip to mark the Bolt and the banjo fitting on the fuel line so the hole isn't abstructed if not perfectly tightend.

 

[jdoni]

****final update**** After completely tearing apart the top end of the bike and checking EVERYTHING I found the issue causeing me to flatline at 8k rpm in every gear. On the bottom of the fuel tank the 17mm bolt that is hollowed out connecting the main fuel line to the gas tank was not lining up properly. In theory when this bolt is torqued to factory specs (16 ft lbs) the hollowed portion of this bolt should line up perfectly with the fuel line. After acting on a hunch I found out that at 16 ft lbs (for me anyways) the bolt was not properly lining up with the fuel line. To ensure that it lined up as it should I made a mark with a permanent marker on the bolt head where the hole in the bolt shank was then tq'd the bolt to factory specs. it was just shy of where it needed to be. so with my calibrated elbow I tq'd the bolt to line up with the fuel line. while I was tearing into the bike I also updated the firmware and re-uploaded the map for my power commander then put her back together. Took the blade out for a test run this morning and she ran perfectly. ***note*** for those of you who have the power commander III usb I highly recommend updating your firmware and downloading the add-on if you havent off the power commander website. Its called an accelerator pump. It gives you a little more control and tweak options to tune your bike to how you ride. I could definitely feel a difference in snap and response when I took her out this morning. Thank you all for your input and suggestions. hopefully this thread will help others find the solution to their own "demons" a little quicker than it took me. 3 days off the road was a little too much for me. :/

How could that bolt not being lined up properly be the cause of an intermittent problem like this? I would lean more towards the PC being the cause.

 

[MattCBR]

How could that bolt not being lined up properly be the cause of an intermittent problem like this? I would lean more towards the PC being the cause.

because it was basically not getting enough fuel... yes it could be the PC... but it turned out to be the lack of fuel d/t the partially obstructed fuel line fitting... it wasn't symptomatic until is was past 8,000 RPM because it didn't need as much fuel

 

[jdoni]

Yeah, but in an earlier post he said that he went up to 145 so I assumed it would be over eight grand then?

 

[miller4254]

i guess i should have been more specific. while tearing apart the bike i did disconnect the PCIII completely and hooked up all the stock connectors back up to the fuel injectors and TPS harness. The bike was still having the 8k rpm flatline issue once I took the bike out for a test ride. so this ruled out the PCIII being the issue. I should have put that in the earlier post to clarify further why I knew it was the bolt and banjo fitting not lining up properly. For the instance where I was able to accelerate up to 145 happened very briefly and was probably sheer luck that the line was able to deliver enough fuel at that moment to get the bike to accelerate beyond the 8k rpm barrier. I to leaned more towards the PCIII myself initially when troubleshooting this issue because until I dug further and really thought about the fine details of the fuel delivery system it was the only "shotgun" fix that made sense.....initially. lol

 

[jdoni]

That's a good catch! Thanks for the clarifying information. Now go have some fun.