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Crappy MPG after mods

Matt C.

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Joined
Jan 12, 2011
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170
Age
37
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Auburn, AL
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Hey guys, I made a few mods to the bike and have since been getting poopoo MPG.

Did the PC3 with JonDaddy82's tune on it from the other site, no flies, BMC filter, have Two Brothers slip-on, fuel line mod, gutted cat, disconnected O2. My mileage after the mod dropped from about 43 to 33. Is that to be expected. I have been a little more playful with the new found power but not that much. Could something be wrong? Is there a better tune. I love the power but dang its sucking the gas down.

Bike is an 06 with 17K miles

Thanks

Matt
 
33 is around what i get with close to the same mods but i have -1,+3 sprockets. jondaddys bike runs good for him but may not be the best for your bike. When i got my holeshot I also got the dobeck controler with his tune and it was not the best. I was lucky to get 28mpg. After a dyno tune it gets 32-34 range. It also gained 5 hp from 8 grand up. My bike still runs a bit rich with two of the adjusters all the way down so i need to change it out with a power comander. This is just how it went for me, I would try a few other maps or get a custom tune.
 
More most =less mileage I get about 33 with half those most but I do a lot of city riding and its a lot of all or nothing acceleration. I don't see a lot of 40+ mpg's on any of these bikes.
 
"More Mod's = Less MPG" is just a wrong concept (LOL) but you hear it all the time. It depends on which mods you're talkin' about. Typically, with a proper tune, any mod that increases the "efficiency" of the intake or exhaust will result in better MPG when riding sanely (as-in commuting, cruising etc. etc.)., but increasing the intake and exhaust also "enables" more fuel/power when JK'ass'in around, which does lead to less MPG.

Cobalt, if you're getting a best of 28, you're either doing 140mph and WOT all the time or you need to lean it it out ALOT!!!!

OP, check out this MPG thread, most people with mods are in the mid 30's. I get around 34 to 38, which seems to be about average for a modded GenII.

BTW: speedoDRDs, gear changes etc. alter your calculated value. keep that in mind when doing your calcs.
 
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Well after I swapped tunes, Im up to about 35-36 city. Not too bad. I havent had a chance to do any highway miles.

Thanks

Matt
 
"More Mod's = Less MPG" is just a wrong concept (LOL) but you hear it all the time. It depends on which mods you're talkin' about. Typically, with a proper tune, any mod that increases the "efficiency" of the intake or exhaust will result in better MPG when riding sanely (as-in commuting, cruising etc. etc.)., but increasing the intake and exhaust also "enables" more fuel/power when JK'ass'in around, which does lead to less MPG.

Cobalt, if you're getting a best of 28, you're either doing 140mph and WOT all the time or you need to lean it it out ALOT!!!!

OP, check out this MPG thread, most people with mods are in the mid 30's. I get around 34 to 38, which seems to be about average for a modded GenII.

BTW: speedoDRDs, gear changes etc. alter your calculated value. keep that in mind when doing your calcs.

Yes you are correct. But when you mod your toys its not usually to ride/drive like an old lady. Just like a turbo will increase mpg (if you dont use it) :p But who does that?
The gf has a flowmaster which can increase mpg but it sounds cool so that doesnt work. Same concept
 
I went for a fairly hard ride on a few local roads along with a trip to my hometown and back and averaged about 39. In town Im back up to about 35-36. I guess I'll take that.
 
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