The Facts:
2006 Busa
Around 5,000 miles
BMC Replacement Air Filter
Hindle Full Race Exhaust
PCIII USB
TRE
AIR Tube block-offs
Busa ran fine, and even after all mods, ran fine for a whole season.
Put fuel stabilizer in it at end of last season with 1/4 tank.
Bike is stored in a medium sized, wooden, outdoor garden shed.
Battery was dead in spring a couple months ago, so I cherged it with trickle charger.
Filled tank the rest of way with brand new 94 octane fuel.
Now for the problem,
Started bike, fine.
Seemed to sound a little more choppy or lumpy than usual,
warmed up to normal temp,
go to take off and when trying to start out in 1st, anything under 2500 to 3000 RPM makes it stumble, and sounds as though it is running on 3 cylinders, it kind of sounds like one of those old air cooled VW motors, a little backfiring, and even stalls sometimes.
Once you make it to 3K and above it takes off and runs almost exactly normal except it seems to use more fuel than usual, or I should say I am going through a tank quicker.
Just to be sure, I pulled plugs which had a reddish brown color on them, but all look the same.
Looked at air box, vacuum hoses, wires, and did an overall visual, but nothing obvious or major, and then I found the coil connector wires were either chewed a tiny bit, or scraped/rubbed, but not broken or cut through all the way. I taped them, and used my tool to check for spark at the coils while running and thats all ok.
I then tried to remove wire connectors off of one injector at a time while it was running to see if the was a noticable difference, and I had a hell of a time hearing if there was a difference. There was some, but not a drastic change.
I even reloaded the PC-III usb map, but nothing.
Then I removed the PC all together to eliminate the possibility of that being bad, and even though it changed the way it ran, it wasn't much different.
The last thing I did waas remove the TRE just in case that had anything to do with it, but nothing.
Finally here's the last thing I noticed. Last night when it had sat all day and was cooled off completely, I started the bike, and raised the idle with the choke lever. and listen the whole time it was warming up. It wasn't doing it right away, and I tried to rev it quick to check it a few times and it sounded fine, and then after about 2 to 3 minutes of warm up after the temp started coming up, there it was again. The running on 3 cylinders thing!!!!!
I checked and adusted the TPS, and there also aren't any codes coming up.
Any ideas??????
The only thing I am thinking is maybe a dead spot in TPS that isn't throwing a code, but causing a glitch at low revs, or a vacuum related issue because i know that the air box flapper is actuated up to the approximate rpm my problem seems to go away.
Just curious, but where does the air enter the air box while the flapper is closed?
HELP!
2006 Busa
Around 5,000 miles
BMC Replacement Air Filter
Hindle Full Race Exhaust
PCIII USB
TRE
AIR Tube block-offs
Busa ran fine, and even after all mods, ran fine for a whole season.
Put fuel stabilizer in it at end of last season with 1/4 tank.
Bike is stored in a medium sized, wooden, outdoor garden shed.
Battery was dead in spring a couple months ago, so I cherged it with trickle charger.
Filled tank the rest of way with brand new 94 octane fuel.
Now for the problem,
Started bike, fine.
Seemed to sound a little more choppy or lumpy than usual,
warmed up to normal temp,
go to take off and when trying to start out in 1st, anything under 2500 to 3000 RPM makes it stumble, and sounds as though it is running on 3 cylinders, it kind of sounds like one of those old air cooled VW motors, a little backfiring, and even stalls sometimes.
Once you make it to 3K and above it takes off and runs almost exactly normal except it seems to use more fuel than usual, or I should say I am going through a tank quicker.
Just to be sure, I pulled plugs which had a reddish brown color on them, but all look the same.
Looked at air box, vacuum hoses, wires, and did an overall visual, but nothing obvious or major, and then I found the coil connector wires were either chewed a tiny bit, or scraped/rubbed, but not broken or cut through all the way. I taped them, and used my tool to check for spark at the coils while running and thats all ok.
I then tried to remove wire connectors off of one injector at a time while it was running to see if the was a noticable difference, and I had a hell of a time hearing if there was a difference. There was some, but not a drastic change.
I even reloaded the PC-III usb map, but nothing.
Then I removed the PC all together to eliminate the possibility of that being bad, and even though it changed the way it ran, it wasn't much different.
The last thing I did waas remove the TRE just in case that had anything to do with it, but nothing.
Finally here's the last thing I noticed. Last night when it had sat all day and was cooled off completely, I started the bike, and raised the idle with the choke lever. and listen the whole time it was warming up. It wasn't doing it right away, and I tried to rev it quick to check it a few times and it sounded fine, and then after about 2 to 3 minutes of warm up after the temp started coming up, there it was again. The running on 3 cylinders thing!!!!!
I checked and adusted the TPS, and there also aren't any codes coming up.
Any ideas??????
The only thing I am thinking is maybe a dead spot in TPS that isn't throwing a code, but causing a glitch at low revs, or a vacuum related issue because i know that the air box flapper is actuated up to the approximate rpm my problem seems to go away.
Just curious, but where does the air enter the air box while the flapper is closed?
HELP!