i have a 2000f4 that is giving me problems when it heats up .It will stall out sitting at lights or just idleing.I have changed temp sensor ,tested stator replaced that and added a new battery too,checked all the wiring and still have the problem. A friend of minehad the same problem on his 2000 R1 he need to replace the main cpu,he told me that was the problem with my bike but since they were diffrent makes i figured his problem had nothing to do with my bike problems.this is my last option since everything else is working and has been tested my question is has anyone had to replace there CPU because of this same problem any insite will be greatly appreciated.

 

ok, Have you messed with anything lately? removed the tank, spark plugs anything? i had a problem once that when it heated up and the bike was at low rpm it was vapor locking. my fuel line accidentally got routed alittle close to the motor, so at a certain temp the fuel would vaporize in the line-stall the motor. if it only does it when its hot, thats significant. You need air, fuel spark and compression for it to run. bring it back down to basics and start there. when its acting up verify all 4 coils are firing and producing spark, verify you have fuel pressure. question: if it starts acting up can you give it gas and save it? or once it acts up its done?

 

actually once she gets below 2k rpms she starts acting up and if i throw in the clutch to downshift for a red light she dies before i get there.Sitting in idle the headligts dim and then the about to stall out starts about 3 seconds later bike dies out but heres the weird part it starts rite back up only to die again.I did what you said in the beginning check the obvious crimped fuel line,lack of vaccum,etc but everything was great so i took it to the next level found out about the sensor and stator changed those but still no fix.But if ya have any other ideas please add im willing to check anything at this point and thank you for the response Stunt!!

 

No problem man diagnosing is difficult, it takes alot of practice and experience. From what your saying it seems fuel related to me. As electrical devices heat up, the resistance grows. I actually just had to replace my fuel pump not for this reason it shorted out. but there is a spec for fuel pump resistance in the repair manual. I can get that for you tomorrow if you dont have a manual. If it was a computer you would think it would have this problem all the time not just when it is hot. Im still thinkin so give me a few ha ha

 

see the weid part is that it starts right back up again... how hot are we talkin this thing gets? like on the little gauge at about 3/4 of the way up my fans turn on. does urs? and is that when it happens?

 

yep as soon as the fan turns on my problems begin but the gauge isnt reading hot just a little past half way,and only wants to stall out at low rpms 2k and under and once the fan kicks on sputter/stalling begins it wont stop till bike gets kool

 

ok, ill get that spec for the fuel pump tomorrow... ill keep thinkin to, im out for the night tho

 

thx again man!!

 

hey man i forgot i left my book in my tool box at work, so ill get that spec to u tomorrow

 

np bro just hopeing to have bike running for the Aces run in Boston August 16th