Error 21, DCV readings suggest bad ECM, looking for a second opinion.

[Angor]

Bike's been surging and every so often when I cut the throttle it'll stumble and completely reset, lose my gauges/etc and the trip meter resets as well. It's only for like a millisecond.

that's pure electrical. factory rubber battery strap or suitable substitute must be in place. cables on both ends particularly battery terminal end must be tight and pristine. i would also remove your flyscreen and check the main feeder harness going to the gauge cluster for connectivity to the cluster. also look at the cluster harness and be sure it's not rubbed thru on a headlight bucket bolt or the horn bracket. rare but can happen. the 2004-2007 EVA units located atop the inner airbox lid known to strip plastic gears due to worn/damaged cable and/or stuck muffler valve. throws error code #21 and historically stores same

I'll check it out, thanks. Maybe an intermittent short or something, the wiring job on the HID bulb fit isn't the greatest on this thing. Regarding the EVA, I'm pretty sure mine is broken, while it gets the 6V and when I cycle it, it doesn't look like it's able to pull the cable completely open, even if I have the cable completely shortened. Moves maybe a half inch? I'm thinking I might buy a new one just for peace of mind.

[user_deleted]

^^^^^ 1/2 inch movement of the cable unacceptable and defeats the purpose of the power valve feature. quality new and used EVA units on evilbay at decent prices with warranties. some 1203 owners disable the exhaust power valve feature via the ecm and wire the muffler valve wide open but if you choose to replace the EVA unit which runs the whole show....which i would do....be sure to lube the actuator cable as well as a high temp penetrant lube on the muffler valve itself. without those 2 items working smoothly and correctly the new EVA unit will strip its internal gears in short order. your stored trouble code can be deleted either by accessing the ecm with spy or similar....or 50 trouble-free duty cycles will also clear the error code.

[rchuff]

I have a spare one and I don't use them if you send me your address I will mail one to you. Just pm me .

[user_deleted]

I have a spare one and I don't use them if you send me you address I will mail one to you. Just pm me .

that right there is what makes this forum the best there is when it comes to buells. very generous offer on your part ricky.

[Angor]

I have a spare one and I don't use them if you send me your address I will mail one to you. Just pm me .

That would be amazing, thank you. I'll send you a PM, we're actually pretty close to each other (I'm in Exton and work in Malvern).

As an update on the bike, I wired it open for now to see if I could chase down the electrical issue, did a TPS reset and now idling fine. Managed to chase down the issue, it's definitely a short, and I think it's in the main harness where it's clamped to the steering head. Managed to regularly reproduce it by turning the bike to full lock to the left, barely needed any pressure at all where the harness exits the clamp at the steering head and it'd short. Looks like that'll be fun getting to, time to do some reading.

Huge thanks for the help from everyone.

Edit: Looking at this I have no idea how I'm going to repair it while it's on the bike.

Edit 2: Just to close this out, got to the harness relatively easily, cut away the wrap and found a broken wire that was hot. Repaired and wrapped it up, running like a champ now. Huge thanks again, and thanks to rchuff it looks like I'll also have a working valve actuator. Looking forward to getting tuned and cleaned up.

[rchuff]

Good to hear and you are welcome. Like I said should be there Tuesday or Wednesday ,you have the tracking number. Let me know when you get it.

[Chicknstripn]

This all good stuff.
The Buell Gods are smiling on this thread