Just picked up a 2011. Bike has V&H CS-1 exhaust, power commander V, K&N filter & I'm assuming the airbox does not have the restrictor because it was in the power commander box with other items. The previous owner had it dyno'd & there is a dip in afr early in the rev range that I'm betting corresponds with the bogging. It dips down into 11:1 territory. Pulling off from a stop, it bogs but pulls through with just a bit more throttle but at any cruising speed around 3-4K it's not smooth...I can feel it kind of surging/hesitating. Is that rich afr causing the surging/hesitating or am I looking at something else that needs work?
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That's lean surging that is in the stock fueling from the factory. I don't know of anyone (including myself) that has been able to fix it with the available adjustments in the Power Commander.
An ECU reflash from Gurued Gear gets rid of the surging and bogging plus every other annoying and possibly harmful (1 lean cylinder as well which is made worse by an aftermarket pipe and tune) bug in the factory tuning.
It's a highly recommended modification, even to an otherwise completely stock bike.
An ECU reflash from Gurued Gear gets rid of the surging and bogging plus every other annoying and possibly harmful (1 lean cylinder as well which is made worse by an aftermarket pipe and tune) bug in the factory tuning.
It's a highly recommended modification, even to an otherwise completely stock bike.
So 11:1 afr isn't the problem? The dyno chart's leaning barely hits 14:1 in one short area at the 55mph area & it's earliest reading is 13.7:1. Then again, I have backfiring on decal so that's either an exhaust leak somewhere or the lean condition you said. There's a missing spring on one of the connectors too.
The lean surge is in a small area around 3500 rpm. On a Dyno pull you would not see it. It's much more obvious at a small steady throttle opening because you are sitting right on that spot. It is annoying because as you describe it is in an area that you can be in while cruising in 4th or 5th gear.
The bog I'm talking about is caused by the throttle being limited and is only in the lower gears at low rpm. Although you may turn your wrist wot, the throttle by wire only opens the throttle part way. The ECU reflash recalibrates how much the throttle actually opens.
The bog I'm talking about is caused by the throttle being limited and is only in the lower gears at low rpm. Although you may turn your wrist wot, the throttle by wire only opens the throttle part way. The ECU reflash recalibrates how much the throttle actually opens.
Okay man...thanks for bearing with me, I appreciate the education. Sounds like Nash flash is on the agenda.
Think I found why I was having the surging problem cruising...this was the worst one but the other three had cracks all the way around. Picked up 1/8" generic vacuum caps from Autozone. They're a bit longer & I think 3/16" is the stock cap size but they fit. Autozone caps are also noticeably stiffer rubber.
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Lil'skeet
Well-Known Member
Did the caps fix the problem? I have my ECU arriving tomorrow from gurued gear. Was very bad at 3k-4500 rpm. Airbox mod, k&n, ufo exhaust 4-2-1, power commander 5, auto tune & double d clutch. I hope the reflash is the fix for it. Still the fastest thing around here but aggrivating at cruise speed.
Between the caps & throttle body sync, a lot of issues resolved. Still plan on reflashing though.
EDIT: Okay, leaking caps & out of sync throttle bodies obviously won't lend to a good running bike but the reflash is leaps & bounds superior to that. Should have done this a long time ago.
EDIT: Okay, leaking caps & out of sync throttle bodies obviously won't lend to a good running bike but the reflash is leaps & bounds superior to that. Should have done this a long time ago.
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