Busa engine sputters when I launch at the drag strip

[Albee]

My 2000 busa 1397 with walbro fuel pump and regulator set at 44 psi. It is map for VP mr 12.. and has a 12iin. Arm. Gearing 1 down 3 up in the rear. With 200lb rider. Problem is lately when I launch at the drag strip for the first 70 foot bike sputters badly then runs good after it wakes up runs through trap at 145 mph. Please help .

[Mr Brown]

Check fuel filter, injectors, engine ground.

[ZeePopo]

Pull the plugs and check the Gap

[ItsDooomz]

Fuel level / fuel starvation?

[jwcfbd]

For some reason the latest replies were submitted as a report to the mods. Here they are.........

• Albee
  
• Yesterday at 11:18 PM
• Report

Has new fuel filter. Will pull injectors and sent out for service. I'll check engine ground thanks for the input

• Albee
  
• Yesterday at 11:19 PM
• Report

Okay I will start there with a new set of plugs and check the gap thanks

• Albee
  
• Today at 3:08 AM
• Report

It's getting plenty of gas

[rubbersidedown]

My 2000 busa 1397 with walbro fuel pump and regulator set at 44 psi. It is map for VP mr 12.. and has a 12iin. Arm. Gearing 1 down 3 up in the rear. With 200lb rider. Problem is lately when I launch at the drag strip for the first 70 foot bike sputters badly then runs good after it wakes up runs through trap at 145 mph. Please help .

Has anything changed since the last time it ran well?
Did it sit? Diff fuel?
Start with the other mem's suggestions. For me,I'd start with the cheapest and only do one at a time. If you get 5 fixes in hand and install all at once without testing each one you wont get an' exact answer to yer specific problem. Then you wont know for next time,plus cant share the fix with the Org so we can add it to our "issues fixed file."
Rubb.

[202mphbusa]

Do you still have the vacuum line to the regulator? When I did. Cracking the throttle caused a rich spike. Plugged that line. Remapped around it. Presto

[rubbersidedown]

It would appear we are more concerned about his issue than he is.
It happens.
Rubb.

[Kevin Jones]

I bet with a video we could hear what sputtering is. Sputtering is a kind of generic term. Could be anything from bogging to a mechanical problem, throwing the lever, etc.

[Mr Brown]

I bet with a video we could hear what sputtering is. Sputtering is a kind of generic term. Could be anything from bogging to a mechanical problem, throwing the lever, etc.

Excellent point.

[Albee]

Has anything changed since the last time it ran well?
Did it sit? Diff fuel?
Start with the other mem's suggestions. For me,I'd start with the cheapest and only do one at a time. If you get 5 fixes in hand and install all at once without testing each one you wont get an' exact answer to yer specific problem. Then you wont know for next time,plus cant share the fix with the Org so we can add it to our "issues fixed file."
Rubb.
[/Q thanks I sent the fuel injectors to MPS for service. Should be back next week before test and tune weekend. I will let you know what happens then.thanks

[rubbersidedown]

Cool. Everything else on the list done or checked out?
Rubb.

[Albee]

Has anything changed since the last time it ran well?
Did it sit? Diff fuel?
Start with the other mem's suggestions. For me,I'd start with the cheapest and only do one at a time. If you get 5 fixes in hand and install all at once without testing each one you wont get an' exact answer to yer specific problem. Then you wont know for next time,plus cant share the fix with the Org so we can add it to our "issues fixed file."
Rubb.

[Albee]

It would appear we are more concerned about his issue than he is.
It happens.
Rubb.

I replaced the spark plug which was burning rich. Got the injectors back from service and set the fuel pressure with vacuum off at 43 PSI before hooking back vacuum. Waiting for next track day to get the results. Will let you know if stops raining here.thanks again.

[rubbersidedown]

I replaced the spark plug which was burning rich. Got the injectors back from service and set the fuel pressure with vacuum off at 43 PSI before hooking back vacuum. Waiting for next track day to get the results. Will let you know if stops raining here.thanks again.

hopefully you are back rocking...
Rubb.

[Albee]

Okay I'm back to rocking. Done all the suggestions spark plugs injectors.. here was the problem. Finally I plugged off the vacuum to the regulator and set pressure to 43 PSI. Went back to Dino and remapped. Now back the hauling ass. Thanks guys for all your help

[Albee]

Power Commander went bad for some reason. Got new power Commander five and remap. Thanks again.

[Hayabusa Wannabe]

Automotive electronics tend to be fairly robust. At the strip you are creating massive heat and that is the death knell for today's electronics. If you can insulate that unit from heat, it may help its life.

[Gen22011]

Hey I have a question I have a 2011 Busa what's a good cam head and piston package to go with want to be able to ride it on the street