I have owned my 2006 Heritage for exactly a year now. Bought it with only 4,301 mile on it. Shortly after purchasing, I added Screamin Eagle II slip-on mufflers, and a SE Stage 1 Air filter, SE plugs/wires, and added a Dyna Jet power commander. My gas mileage has been rather disappointing to say the very least. My boss has a 2005 Heritage, stock, and he gets 190 miles or more before his low fuel light comes on. Mine consistantly comes on between 130 - 140 miles. When I eventually find a gas station to refill, I'm usually putting in around 4.3 gallons, so is my boss. What gives? Adding slip-ons and an air cleaner isn't going to cut my gas mileage THAT drastic! I spent an hour today talking with my guys in the local HD shop. They highly discourage using the Power Commander, and infact, will not install them. They recommend that I have the "generic" ECU download done, and that "should" fix my problem. Before I spend $180 to get this done....your thoughts?

 

A generic download won't fix the issue.

Did you have the power commander custom mapped on a dyno, or is it a can map off the web or from the seller?

It needs to be tuned properly...

 

you're getting 31 mpg, and your boss is getting 44. do you do the same kind of riding? a stock heritage is supposed to get 35 in the city, and that is probably driving very conservatively. you might not have a problem at all.

 

The DynoJet is a Power Commander III from Fuel Moto. Email them with your detailed configuration and tell them you would like to improve your gas mileage. They will have several options for you.

I installed their DynoJet on my 2003 Heritage and yes I have lost some on the MPGs but overall performance is way up.

 

It's a can map from the power commander/dnya jet website.

 

That's a difference of around 13mpg. We both live in/around the same area and do similar driving. I can't see losing overall 65 miles just by adding slip-ons and an air filter?

 

Have your bike tuned professionally on a dyno. Ask that the tech tunes it for mileage if that is what you are looking for.
I usually ask that it is tuned some what in the middle of good performance and mileage. I have never been diappointed this way. This will also cure any heat complaints also.
Hope this helps,
John

 

I have an 06 Street Glide with a Doebeck TFI and get low to mid 30's on the highway. I can get better mileage depending on speed, wind and how I ride it. I usually ride it like I stole it. Honestly, I have a few friends who get that kind of mileage (mid 40's) It's usually a stock bike (read lean). Or they don't have it set up right (read lean). A little rich is alot better than a little lean.

 

I would say, riding style can have a lot to do with it, some people ride more agressively, I tend to be one these people, thats how I get my kicks, I've only just got into the Harleys , and I come from a sports bike background, I bet I'm not the only one, I dont know what my fuel figures are, and cos I dont do a lot of miles I dont really care, but I know its not as good as some of the riders I've spoken to.

 

Whoa .... hold it man...read his post again...he has all....SE MOCO stuff....that "generic" map is "SPECIFIC" to the SE MOCO stuff he added. Map download is "tuned" by MOCO at factory.

Some people (not me) would say it don't get better than that. And...if he goes to right dealer...like Ft Myers FL Harley....they have a dyno....factory trained dyno and tuning guy....and they work on anything....MOCO stuff..or third party.

Dude...take a shot at the download IF you are done modding. $180 is peanuts to get the bike running right. Bad mpg is a symptom of bad mapping. If you are gonna do more shtt in the future think of an aftermarket ECU. I know nothing of SERT....and I cannot give you advice on it.

I'm a tweaker ... no matter how good the basic map... I always mess with it ...its in my nature.

I know Tmax works cause I have one on my fatboy. I set up a guy on this forum with a tuned file and he is getting 52 mpg. Today I was getting upwards of 45 and I was doing 80-85 on my way to Ft Myers and the bike was running so strong I was throttle-happy...and I'm wringing every HP I can out of a non-cammed Stage 1 2010 96b.