Anyone tuning at altitude?

[AZkneeslider]

Hey everybody,

All of my riding is done at 3500 to 7000 foot altitude.
Most of my previous (not Buell) tuning at these elevations was with carbs (old guy), generally you would lean the jets some and add a little timing into the bike.
I got the ECMSPY and followed parameters and warmed up and all, looks OK, AFV was at 98%.
I went ahead and reset TPS and AFV to 100, and did relearn test ride.
It runs good with the usual popping on decel.
It is a 2006 xb12ss with K&N and Magnaflow pipe (similar to Deans).
What about these Buell's though, any thoughts?
Any Snap-On scanner users? Is AFV the same as fuel trim?
If the AFV stays nears 100 on it's own, does that mean it's all good?

Thanks, Jim

[Cooter]

Set the AFV at 100%

A K&N and Magnaflow with a stock ECM? Like any FI system, the Buell DDFI will adjust automatically for altitude, but if you are running a stock ECM with those bolt ons it can't adjust enough. It also explains the de-cel popping (lean). A "race" or programmed ECM for your application makes a HUGE difference.

I've only used my Snap-on scanner on cars, so I don't know if it's labeled as Fuel trim? But I do know if you set AFV at 100% and it stays there, that is good.

[AZkneeslider]

Yeah, I hear you.
My laptop is in getting fixed,
I'm looking at it with my bike on the porch and a 20 ft ext cable to my desktop till then.
Thank's.

[afpreppie04]

I've only used mine on cars too, but AFV would be sort of similar to LTFT. As long as you get it to stay around 100 you should be good.

Out of curiosity, are you talking about the Flagstaff area? Beautiful place, I always try to go through there on my way west.

[AZkneeslider]

Yes, I've only used mine on cars also, I was trying to compare terminology, Yes LTFT!
I'm surprised Buell's don't use a MAP sensor, but I see in the ECMspy tuning guide, you can add one. Guessing for Turbo's?
I'm just south of Flagstaff.

[Maneba]

Used my xb12ss 2009 at 3000 meters with lambda off and ECM tuned by Twinmotorcycles and had 0 problems, very linear.