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Average MPG?

SpringerSteve98

Active Member
Seems like my MPG is rather lower than what i'd like. I'm gettin an avg of about 35mpg (using non ethanol whenever available) under normal riding conditions. I can get a few more mpg's while trying to stay out of it, but not much.
I have a stock 80ci EVO. The only mods are ultima full headers with torque cones, Jetted the stock CV carb, and a K&N air filter. Its had a dyno run to make sure its not running lean/rich... It seems to be set where it needs to be. I was expecting 40-45mpg. But thought i'd ask what you guys have been getting. I should add I've been running around with a windshield and large saddlebags, and 2up most of the time (but she's so little she almost doesn't count).
 
My '93 Heritage is also 80ci. My mods are 20 over bore, andrews cam, high comp pistons, V+H straight shots. I'm running the stock carb and average 45-48 mpg.

These mods were all done by my buddy before I bought the bike. Not sure what it did before that.

I'm also using a shield, bags and almost always 2-up. Running 92 octane.
 
Well... I've thought about that. And thought mabye i'm running in the wrong gear on the highway or something. Seems to me like 55-60mph is almost right between 4th and 5th gear. (i catch myself wanting to hit 4th going up hill or around slow corners 50mph or less)
 
One other thing to check is dragging brakes due to sticky piston seals or unlubed pins. Brakes should only give a intermittant swishing sound due to brake rotor runout. If heavy drag, you may need to do caliper service and fluid changeout/bleeding.
 
I seem to coast fine... although thats something i hadn't thought about. Seems like something i'd notice though when i pull the clutch in there doesn't seem to be any noticable drag. But then again how much drag would it take before it eats 5 mpg or so? I think i might put it on a lift to see if the wheels spin freely in search of an easy answer.

I'm starting to think my jetting is the issue. I have no heat shields and they are blueing quite nice. (most avg riders say thats normal) Makes me think its lean. But when i first start it and rev it while semi-cold (not running any enricher) there is a bit of black smoke (which seems rich). I think i'll go buy a couple sets of cheap plugs and go out on the highway and get a read on it. Then do the same in town just putting around and see what i find out.
 
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I check it against the odometer and amount of gas I put in every time. I do it on my cars too. Something my Dad drove into my brain. I'm getting about 43 MPG. A little less if I am riding in the canyons and a little more if I'm on flat ground.
 
Well i went out on the interstate and checked the plugs... went about 20mi then pulled them... I was running about 80mph when i killed the engine (and 20 miles before that). They looked fine. Mabye a tad rich on the town plugs, but nothing serious enough i'm worried about changing it. I think it might be the pipes more than anything. They are pretty much 2 1/4 inch drag pipes with turndowns.
 
OK... So, still not happy with how my baby was purrin i went to a good friends house today. He knows his stuff a ton better than i, and i wanted to break into the carbs convinced it was a jetting issue. This is what we found...
Pilot - 40
Main - 180 (with the clip set very fat)

He told me that most evo jet kits run a 45 pilot, but after looking at the jets themselves they were from a dynajet, or dynojet thundersomethingorother. So we dug around and found the actual instructions, and what was reccomended. This kit used the stock pilot jet, which in my case was a 40. We upped it to a 42 to try and help the more than occasional "cough" while starting. When we pulled the main jet it was set one notch from as rich as it will go. (second clip from the bottom) We took apart the accelerator pump and the rest of the rubber components and soaked it in chemsol for about an hour. Took everything out and cleaned it well. He pretty much put it back together while i took notes. While putting it back together he noticed that when the throttle was triggered the accelerator pump was shooting all the gas into one cylinder. So we adjusted the needle so that it sprays directly onto the needle creating more of a mist into both cylinders. We did this by filling the bowl with gas, then holding it (away from your face) and manually twisting the throttle assembly and watching where it sprays, If it was too far one way or the other open the bowl, and use vice grips to twist the thicker portion of the spray needle. (i believe its pressed in there)... We moved the clip on the 180 jet two notches up and put it back together. Runs like a brand new bike.. I filled it up to test the MPG to see if it got better. I have a feeling it did.
 
Steve, glad you got it sorted out. Never thought about rotating parts to optimize accellerator pump spray evenly, which goes a long way regarding doing those "extra credit" activities to get the job done right after school...good job there! :cheers
 
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