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Gas mileage took a dive

11bdad

11bdad

Member
Installed a TFI unit on my 2010 FXDC several months ago. Bike has Rush Slip-on's (1.75 baffles), and a Ness Big Sucker AC. Bike has run great since I installed the unit (still does), but my MPG has taken a dive over the last 3 tanks of fuel. The TFI is set to the recommended setting for the mods. My mileage has gone from 40-42 mpg to 36-38, with no change length of trips or riding style. Any ideas?

Thanks
 
You can lower the #1 and #2 pots just a bit but the decrease isn't drastic for openers. The engines are set so lean from the factory that the added fuel will make a slight difference in MPG.
 
I cooler, great running bike is worth a few miles a gallon. Longevity alone is worth it. Dont worry, drive it like you stole it.
 
My thought is, now that it running great and pulling strong the amount of noise you are making do to the right wrist is indirect relation to less MPG.....
 
I think dbmg hit it right on the head. After I did the same upgrades I lost some MPG until I quit impressing myself with the new found power and sound. The MPG will come back some what. Injoy the new power and sound.
 
I guess I was a little vague in terms of the time frame. I installed the TFI probably 5 months ago. The pots were adjusted to the recommended settings and everything has been great. My gas mileage since installing the unit has been between 38-42, which is a combination of in town riding with 1 or 2 50 mile trips to Charleston a week. The drop in gas mileage has just occurred in the last 3 tanks of fuel. I'm not getting on the throttle any more than usual. I just don't understand why I've gone from an average of say 40 mpg down to 35 to 36. As good as the bike runs, I guess I won't worry about it.
 
11bdad said:
I guess I was a little vague in terms of the time frame. I installed the TFI probably 5 months ago. The pots were adjusted to the recommended settings and everything has been great. My gas mileage since installing the unit has been between 38-42, which is a combination of in town riding with 1 or 2 50 mile trips to Charleston a week. The drop in gas mileage has just occurred in the last 3 tanks of fuel. I'm not getting on the throttle any more than usual. I just don't understand why I've gone from an average of say 40 mpg down to 35 to 36. As good as the bike runs, I guess I won't worry about it.
Click to expand...

Did the last 3 tanks come from the same filling station? Have you put in any kind of fuel stabilizer - sea-form,MM,Iso-heet ?????
 
Two tanks were Citgo 93 octane (no ethanol) and today was BP 93 octane. Normally all I run is the BP, but I thought I'd run some ethanol free in it since the station is pretty close. No additives have been added.
 
11bdad - Glider's suggestion is correct to get a little fuel mileage back by turning the first 2 pots down just 0:30. Losing 4 mpg isn't real bad though for a stage 1 setup to get the torque and HP increase.

Honestly though we will have to agree with a number of the other forum members about the quality of fuel more than likely being the culprit.

Merry Christmas everyone.
 
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