'08 XB12S runs poorly

[psittacid]

My 08 XB12S has the following issues:
- at startup, it dies at idle, even in warm weather.
- it fouled a plug, which was cleaned and reinstalled.
- Even after warming up in my driveway for a minute, it bogs and requires revving and slipping the clutch when accelerating from a stop. It does this for about the first 5 minutes of riding.
- when accelerating beyond 4000rpm, it is not smooth and does not have the power it should.

My local Harley shop has had it for 2 weeks and has not yet diagnosed the problem. I know that they have had it on the computer for hours while talking to tech at Harley corporate, cleaned the plugs, installed new parts (jets?) in the injector. My last 2 tanks of gas were from different name-brand stations, and the problem persists; I do not think bad gas is the problem.

Any ideas? Thanks in advance.

[GatorBuell]

My guess would be Coil, tps sensor or ECM went bad.

[psittacid]

Thanks for the reply. Do you know which (if any) of those would show up as error codes? The guys at the shop seem determined to find the problem with a computer. I'm guessing that the problem cannot be found that way or I would be riding today.[smirk]

[derek twist]

Taking my xb12ss in to the dealers for the second time tommorow with the same problem will let u know if they fix it

[gbalias]

have them check and verify the intake air temp sensor is working properly...as well as the engine temp sensor. these will dramatically affect the fuel enrichments and foul plugs, cause sputtering, etc.

youd be surprised how 'little' the dealer knows about the buells. unless of course, theyre well known for their buell techs. which, i dont think ive run across any.

[sharur]

I have a 08 xb12scg, which I acquired recently. My very first ride was a disappointment since it exhibited all the issues that has been described by psittacid. The folks who sold me did not have any such complaint and it was a puzzle how this problem surfaced during transportation. I hooked the bike to the trusty ECMspy software, but there were no trouble codes and all diagnostic tests completed without any errors. Taking it to the dealer, I was told it was a bad exhaust valve actuator. The actuator test performed with the ECMspy did not show problems and neither did your simple method of unhooking the actuator plug and reconnecting, or holding the throttle open and turning the start/stop switch on the handle bar.
Ultimately, the bike is running fine now after the actuator was replaced. Just sharing the info on what was one to my bike.