drop in MPG's

[2wheelingdawg]

I've noticed my mpg's have dropped. I'm barely getting 40. I used to get mid 40's all the time. I noticed the drop about the same time i had a bad case of farkleitis. I added a Givi 46 and 2 bros exhaust. Does the top case cause more drag? or is it from being able to hear the bike growl, giving to much gas? I probably average 80mph on the highway going to work.

 

[NMRoadRunner]

Does adding several square feet of surface area cause drag? :blink: Is this a trick question? Is this Friday?

 

[RiderCoach Lar]

Does the top case cause more drag? or is it from being able to hear the bike growl, giving to much gas?

My guess would be it's a little of both. The top case is going to create a little added drag, especially at those speeds, and there's no doubt your ears are encouraging your right wrist to play some rugged tunes

 

[jjsC6]

It sounds like a combination of things. Yes, the top case will add drag - but no way do I think it would make more than 1mpg (if that) difference. The pipes could have messed with the fuel mixture due to a change in the 02 readings, if you added a PowerCommander, that will make a difference (made a big difference on my bike), summer fuel makes a difference, hot weather makes a difference, and it could be that you are riding faster.

 

[chrisflock]

I'm going to agree, you're looking at a combination of the added drag from the top box, a little more air flow from the exhaust, but probably a significant factor is that the devil whispering in your ear through the sound of the engine has gotten louder...

When the exhaust system on my old pickup "fell off" (what are the odds that of hitting a reciprocating saw and it cutting off your exhaust system one sunday afternoon?) and was replaced with a cherry bomb glass pack, my gas mileage mysteriously went down about 3 mpg, but then over the next few months slowly increased up to 1 mpg better than before.

My theory was that with the new exhaust, which wasn't much louder but about 90% more bad-ass sounding, when I shiftered I had a tendency to not let off on the gas as quickly when I pushed in the clutch, so then the engine went 'vaaarooooom pop pop pop...'

But after a couple months, I got used to the cooler sound and did that far less often.

 

[03HiYoSilver]

2Wheel,

It could be the fuel, as of July 1, 10% Ethanol is now mandatory. See this link for the detriments:

https://www.fjrforum.com/forum//index.php?s...st&p=430273