Hello,

I'm new to this site but not to owning H-D motorcycles. I have a 2006 Street Glide which has never really ran right. It is fuel injected (open loop) with Screamin Eagle Air Filter, Rinehart True Duals, and a Power Commander. It has been dyno tuned twice now. Bike runs great when throttle is on, the problem arises when the throttle is off.

An example of what it does: Run the bike up to 4000 RPM in third gear, then let off throttle, coast for a few seconds. Touch the throttle and POW, backfire through pipes. Don't touch the throttle and as it passes 2000 RPM, it will pop, surge, and begin to act normal. The same for coasting down hill and increasing RPM's, normal operation until 2K RPM is passed, then it starts to act up.

Here is a poor description of how it sounds: During decel, the bike should go, blub,blub,blub,etc. as the RPMs decrease. Instead mine goes Blaaaaaaaaaaaaaaaahhh as it decels until 2K RPM, then pop, surge, blub, blub, blub, etc.

I have checked for exhaust leaks, intake leaks, and messed with tuning to no avail. The bike runs perfectly fine when it is cold, but when operating temperature is reached, the problems begin.

Please Help!!!

 

Sounds like you don't have the right base map for your bike (perhaps too lean in some rpm ranges, two rich on decel). Dyno tune probably only looked at making power, not drivability. What model power commander are you running?

 

I have been fooling with the tune for about 3 years and 20K miles now. I have been as far as +60 rich and -60 lean on the zero and 2% throttle positions. Same problem either way. I also unplugged the Power Commander and ran without it. Same problem.

It is a PCIII-USB with the latest firmware update.

I tried something new this morning. When I was decelerating, I hit the kill switch and then turned it back on. Sounded the same either way. If I kill it above 2k rpm allow it to decel for a while, then turn the kill switch on below 2K rpm, same effect as allowing it to decel that far, pop, surge, correct running.

There is something wrong with the bike. It is not a tuning issue. Not to sound defensive but, as I said, I am not new to owning a Harley, and I have tuned them before. If it was tuning, I would have it fixed by now.

 

There has to be something wrong with the bike then.... I can can only guess the usual suspects that you've already checked like a vacuum leak, bad gasket (intakes and exhaust), bad valve(s), perhaps temperamental injectors..... cam or cam timing out of whack, crankcase timing sensor out of whack, MAP sensor (if it has one) out of whack... frustrating to say the least. Sorry

 

I had a problem similar to this on the 03RK and I finally took teh injectors out and cleaned them. I never saw any debris but that cured the decel poping and weird studdering when rolling on the throttle.
...gene

 

Questions:

1. do you have 8 degree or 25 degree fuel injectors in it?
2. call Fuel Moto and tell Jamie what it is doing and double check to see if you have the correct map.
3. Is your bike throwing any codes?
4. Have you changed out your spark plugs?
5. Have you tried some techron or redline SI-1 fuel injector cleaner in the gas?
6. Have you cleaned your throttle body, MAP sensor and intake air temp sensor? (use only TB cleaner that is safe for electronic sensors).
7. Have you checked your fuel pump pressure?

My guess is you have a PCIII tuning/timing issue. But any of the above could cause erratic performance

 

Have you set the throttle position on the power commander? Just another question to consider.

 

All good questions. The only thing I can say is that the bike has done this since new. So any dirt or spark plug problems are essentially eliminated. When new, I assumed it was a tuning issue, so I spent my entire warranty period trying to tune it out. Don't know what injectors it has, whatever is stock. No codes are present.

Throttle position on PC has been set, but, as I stated, I removed the Power Commander and had the same problem, so it is not a power commander issue.

Last night I tried something different. I placed a timing light on the bike and went for a ride. I ran the bike up to 4K rpm, hit the trigger on the timing light, then let off the throttle. For about 1-2 seconds the spark goes away then recovers and begins to spark again. If I touch the throttle and get back off quickly, another 1-2 seconds without spark. This happens on both cylinders. This does not occur below 2k rpm.

Sound like a bad ECU??? Crank trigger was replaced once before and the problem persisted, so what else would control the spark?

 

I have an 07 Street Glide w a 96, Sinister Header, Screamin Eagle A/F, and S&S 510 Cams. I run a Power Commander 5 on mine. I've fought this for weeks now. I've pulled heads had checked for burnt valves, readjusted push rods, changed coil and wires, ran with no Power Commander, etc. I'm out of things to try. Bike has 7K on it. Bike runs great after start up for about 30 to 45 seconds the horrible pop, spit, backfire etc. I thought it was heat related but I just realized when it does it I can hit run switch off yet leave ign on, Re-fire and bike runs perfect again for same time period. Clearly something is switching on or off and creating issues. We have such a short riding season here any input would be amazing.