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Everything else seems fine but, as the title says, the bike stalls at idle after warm up. This usually happens on cooler days (70 degrees F and below). It seems like it's just barely getting enough fuel to not stall all other times. I've got Supertrapp Fatshots (open ends) and upper and lower airbox is removed w/ Amsoil filter. Sensor is relocated to lid on air filter. Got a SEPST. Where should I start to make it richer at idle (kPa)?
 

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...the bike stalls at idle after warm up. This usually happens on cooler days (70 degrees F and below). It seems like it's just barely getting enough fuel to not stall all other times. I've got Supertrapp Fatshots (open ends) and upper and lower airbox is removed w/ Amsoil filter. Sensor is relocated to lid on air filter. Got a SEPST. Where should I start to make it richer at idle (kPa)?
The idle mixture control is a combination of the AFR target at low RPM and low MAP, the VE values of the front and rear cylinders at 0% TP and low RPMs, and the "warmup enrichment" AFR values.

I don’t have the SEPST software (I use the SERT/MasterTune software) but there should be similar tables/values in the SEPST software. The MAP at idle is around 20 kPa so you could try lowering the target AFR at 1200 RPM and 20 kPa. You could also raise the AFR enrichment values for lower temperatures in the "warmup enrichment" table. Both these techniques will change the mixture for both cylinders. The other places to adjust are the two VE tables. If you raise the VE values at 0% TP and 1000 to 1500 RPM (idle RPM is up to 1600 when cold) this will enrich the mixture also.

How do you know it's lean?
How are you measuring AFR?

If you don't have some way to measure AFR this will be a guessing game at best but using what I posted above should help if you don't have some other problems like an air leak or bad spark plugs.
 
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