poor cold running and hot starting

[turbo2]

Hi
I'm new to this forum and need advice! My 2000 Busa has had this problem on and off for getting on for three years; no-one has been able to sort it!
Starting from cold I have an intermittent misfire; it feels like the bike is running on 3 or 4 cylinders. Once hot, this continues up to 3000rpm. After about 30 miles, she usually runs fine.
If i ride for an hour or two and leave the bike for a few minutes only, she'll start fine. If I leave it for about an hour, it often wont start; cranks over but I cant hear the fuel pump. the only solution is to leave the bike for another 30 miles or so.
Recently I've had a major service.. the plugs are new, the valve clearances are fine, fuel pump filters seen to, throttle bodies are synchronised but the problems remain.
I have done 48000 miles, all services have been carried out.
ANY IDEAS ANYONE?
Thanks Ed

 

[Busaman5000]

Hmmm have you checked the thermostat? Perhaps its stuck.

 

[99'busa]

have you had the fuel pump cleaned?

 

[99'busa]

btw

to the org.

 

[Busaman5000]

Have you done any mods to it such as a power commander?

 

[turbo2]

The pump has been cleaned, there have been mods like power commander. Dont know where the thermostat is! However, I wonder if the misfiring problem is caused by a faulty coil pack?

 

[99'busa]

have you had the injectors prof. cleaned

 

[99'busa]

this is a slow time of day. dont worry lots of very knowledgable guys are gonna give you input

 

[Busaman5000]

Try unplugging the powercommander and see if that helps. Ive heard of these things going defective.

I hope some knowledgeable people show up as 99'busa says. Because im just taking stabs in the dark really.

 

[rocketgeezer]

Turbo try unpluging the PC that dont cost anything, partialy clogged injector maybe? but I have a bud that works at the local Suz Dealer and after a couple of weeks of this and that it was a coil pack causing the problem

 

[Projekt]

However, I wonder if the misfiring problem is caused by a faulty coil pack?

BINGO!

1. Read the plugs after starting the engine cold and running it for just a minute, this will lead you to the suspect cylinder as the plug may be coated with raw fuel.
1a. When you find your suspect, simple swapping of components will narrow down the possible causes.
 1b. Try swapping the coil packs and trying this test again to see if your indications move with the suspect coil pack.
  1c. Swap the injectors around after troubleshooting the coil packs if you don't find them performing sub-par.

2. Perform a compression check since lower compression in one of the cylinders can be a cause for your symptons due to less heat.

3. If you have dismantled the bike to any degree sometime in the past, inspect all of your electrical contacts. Everything!

4. As noted above, it wouldn't hurt to have all of your fuel delivery components cleaned and flow tested. A weak flow out of one your injectors will contribute to this behavior.

 

[Copperone]

I had a very similiar problem on my 05. I bought it used and it came with a power commander. Very rough starts but after it warmed up it was fine unless it sat for an hour or so. Once again hard starts or maybe not at all for a while. I unplugged the power commander and the bike ran fine. No problems. I sent the PC for testing and they replaced it.