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Retuning a TFI twice a year

Retrop

Active Member
This is for the Dobeck guy. Would it be advisable to turn the screws on the potentiometers back to zero a couple of times a year and retune? I am thinking that it might not hurt to retune in the fall when the oil companies reformulate the gas for the winter blend and again in the early summer when they reformulate again for the warm weather blend. My reason for asking is that I have started to get a little popping during the cold weather that was never there before. I am thinking that it could very well be because of the reformulated ethanol in the winter. Am I dreaming here or could there be some wisdom in seasonal retuning?
 
Good question! Did you try fattening it up a little? If so did it help?
 
We have lots of snow on the ground right now but I've managed to get in several rides this winter when roads were ridable but very cold out. My bike definitely wanted more fuel and I bumped up my settings a little. I can only imaging my motor had to be running at least 30° cooler due to the cold air and wind chill factor during these rides. I had my "summer" settings jotted down and I'm sure I will need to dial it back once the weather warms up again.
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Any device that adds-on to the ECM has these type issues. You set them for the conditions your in and the way the ECM is handling them. When those conditions change as they do when gas changes or hot or cold weather happens. So you use your best guess when the weather changes and the fuel changes and start adjusting again.
 
Good question! Did you try fattening it up a little? If so did it help?
Actually, in order to get rid of the slight pop I retuned all four potentiometers. I turned all screws back to zero and started from scratch with the motor at normal operating temperature. Ultimately the green pot went from 2 1/2 to 2 1/4 (less fuel). The second, third and fourth remained at 3 1/2, 3 1/2 and 4.
The pop went away. This is with a Stage I bike. I suspect when the summer blend of gasoline arrives, I will have to fatten up the first pot again. By the way, the EPA says that refiners switch over to the summer blend during March & April.
 
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