Fazed and Confused
Member
Any help, ideas, or suggestions will be greatly appreciated. I've spent all the time I've had over the past couple of weeks trying to get this straight and I'm out of ideas.
Mods at the beginning:
LARS airbox mod
BMC Filter
Leo Vinci Slip-on
Chronological order of events:
1) Picked up a used Power Commander 3 and installed it. (it didn't come with the O2 sensor delete and I didn't know about it till later)
2) Ran fantastic, no issues at all, nice and smooth.
3) Decide to gut the cat.
4) Take the slip-on off preparing to gut the cat and decide to ride it without the slip-on and the cat still in it. Why? Because LOUD NOISES and I'm a little kid when it comes to stuff like this.
5) On this 1-2 mile ride with the cat, but no slip-on, it runs awful <5,000 rpm, but sounds glorious over 5k rpm. I assume the jumpy rpm down low is just due to minimal back-pressure.
6) Don't think anything of it and proceed with gutting the cat.
7) Put everything back together, gear up for a day of riding, and... still runs rough under 5k rpm.
8) After I throw a temper tantrum I get on the computer and find others who had the same issue and it was due to the O2 sensor. Perfect! Order the dummy plug for the harness and plug the exhaust.
9) Put everything back together and... still no change.
10) Try different PC maps, no map, turn the idle up, everything I can think of (which wasn't any more than what I listed) to no avail.
When I cold start the engine everything runs well, no issues at all really. It warms up and settles down and it just can't maintain RPM. From normal idle it will jump up 300-400 rpm, then go about 100-200 rpm under normal rpm, then straighten out before the cycle starts over. When riding at low speed it's the same way. It isn't safe to take a turn in gear with it jerking like this. It nearly bogs down when you get into the gas and once you get around 5,000 rpm it runs fine.
I don't know what my step is. The only thing I can think of is to flash the ECU, but I don't actually think that would fix this. It throws me off how it happened instantly when I ran the bike with no muffler installed.
I have read every potentially relevant thread I can find and can't find a solution.
Mods at the beginning:
LARS airbox mod
BMC Filter
Leo Vinci Slip-on
Chronological order of events:
1) Picked up a used Power Commander 3 and installed it. (it didn't come with the O2 sensor delete and I didn't know about it till later)
2) Ran fantastic, no issues at all, nice and smooth.
3) Decide to gut the cat.
4) Take the slip-on off preparing to gut the cat and decide to ride it without the slip-on and the cat still in it. Why? Because LOUD NOISES and I'm a little kid when it comes to stuff like this.
5) On this 1-2 mile ride with the cat, but no slip-on, it runs awful <5,000 rpm, but sounds glorious over 5k rpm. I assume the jumpy rpm down low is just due to minimal back-pressure.
6) Don't think anything of it and proceed with gutting the cat.
7) Put everything back together, gear up for a day of riding, and... still runs rough under 5k rpm.
8) After I throw a temper tantrum I get on the computer and find others who had the same issue and it was due to the O2 sensor. Perfect! Order the dummy plug for the harness and plug the exhaust.
9) Put everything back together and... still no change.
10) Try different PC maps, no map, turn the idle up, everything I can think of (which wasn't any more than what I listed) to no avail.
When I cold start the engine everything runs well, no issues at all really. It warms up and settles down and it just can't maintain RPM. From normal idle it will jump up 300-400 rpm, then go about 100-200 rpm under normal rpm, then straighten out before the cycle starts over. When riding at low speed it's the same way. It isn't safe to take a turn in gear with it jerking like this. It nearly bogs down when you get into the gas and once you get around 5,000 rpm it runs fine.
I don't know what my step is. The only thing I can think of is to flash the ECU, but I don't actually think that would fix this. It throws me off how it happened instantly when I ran the bike with no muffler installed.
I have read every potentially relevant thread I can find and can't find a solution.
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