Hey, guys. I have a 2010 RKC with the factory 96, 255 cams, Super Tuner with dealer dyno tune, stage 1 air filter, and Rush slip on mufflers.

Before the cams and new tune, I could routinely get 250 miles out of a tank, and now I am lucky to get 200. In fact, I am usually looking for a gas station at about 150 miles, which is yielding 35mpg or less, roughly. And I don't ride exceedingly fast or make a habit of hard accelerations.

So...what can I do to help the fuel efficiency of my bike? I like to plan long rides every so often, between 1,000 and 2,500 miles, and I would like to get my bike to peak efficiency. I invested a lot of time and research in tuning my diesel pickup for peak fuel economy with great results, but I have no idea where to start with a V-twin.

Is it possible that I have a less than ideal dyno tune? The bike runs great...plenty of power for what it is.

Would upgrading to 103 jugs help me out, and going with the Screamin' Eagle base map on the Super Tuner software?

What about a Power Commander? Do they offer a more efficient tune for the 96 with 255 cams?

Any helpful input would be appreciated. I keep hearing of this mythical 45+ mpg that people talk about, but I am nowhere near that.

 

The more horses you have the more feed they need.

 

with cams it'll be hard to restore near stock mpg.

a catless header will help to pick some up though

the prime culprit is probably the tune and it may be improved, regarding the pcv I smell lots of rich running bikes with pcv's. the "tuner" just makes everything rich, 'cause "rich" means more power, right ? ( no)

my MPG is right at 43 mpg measured over thousands of miles at 70 mph.

2009 FLHTC ( so more weight and wind resistance than you).
96" ness big sucker, stock headers ( no cat in 09) and supertrapp tuned mufflers.
My ECM is stock, I have nightrider.com XIEDS on my o2 sensors

I deliberately sacrifice the power gains of cams for the mpg I need/want when touring

building your motor further ( 103" etc.) will increase comsumption

Mike

 

Very insightful...thanks. I guess I should point out the obvious: I'm open to changing my setup however necessary to tune for peak fuel economy, including downgrading power or swapping cams again to something more suitable for highway cruising. Does anyone have any experience with this type of tuning specifically?

I know the 255 is a strong bottom end cam and probably not ideal for long hauls. All of the reports on here, however, suggested that fuel mileage did not change after a 255 swap. That's why I'm wondering if I have a bad dyno tune.

 

When I first got my FLTRUSE I was getting no better than 36 MPG. After my Stage lll up grade and dealer dyno I was averaging only 30 MPG!
My tuner was the SE which later I found to be CRAP!

After doing my research, led me to Doc Weaver in Mineola FL. He had to install the TT Master Tuner. He spent 2.5 hrs on the fuel map alone. After several hours he got me another 10 HP & 10 TQ. I no longer have throttle hesitation and my fuel average is 40 MPG!

You need to find a reputable tuner with great references in your area. Have it retuned and dynoed!

Here are my mods:

Stage lll Engine *Modifications:
Sach's Polished & Ported Heads, TTS MasterTune, T-Man 625 Cams, Adjustable Push Rods, Full Sac 2" Baffles and X-pipe, SE 10.5: 1 Forged Pistons, Titanium Valves, *Dyno tuned @ 110HP 120 TQ.

 

Not trying to be funny but how much air is in your tires? At 70+mph I get 38-42 mpg. 99% of my riding is 2 up and fully loaded. Your 255's are fine. Any performance cam is gonna hurt fuel economy.
Around town and short trips I usually get 36-38 mpg.

 

Do you have your cables for the SE Pro? If so, you could open the map and see if they are running a rich open loop AFR table. If you have trouble with that process, go to the ECM section of the forum and post in the SE Pro tuner sticky post. Many people can help you out.

BTW, no 255 cams but 96" duals, pipes, AC and SE Pro and I've done my own tuning and still get 42-44 mpg.

 

The 255 is ideal for long hauls on a touring bike. You should have plenty of nuts to pass without a need to downshift. From what I understand, you should be at 40+ MPG as well. I will be finding this out for myself shortly.

mikebaby

 

It's not the cam, It's the TUNE!! You have become another proud owner of a motorcycle from a dyno operator that believes the more fuel he pours in the motor it will run stronger and cooler. Sorry, but it doesn't work that way.

 

Not surprising, but like DBagr said the mileage change isn't due to the cams. It is common for tuners to add fuel to the cruise range to enhance cooling and part-throttle response, and it is probable that your tuner went in this direction. My tests have shown this to be only of minor significance, however, but mileage suffers noticeably when AFR's get too rich.

I have a Power Vision, which is another flash-based tuner similar to your SEPST, and I have the bike running with 255 cams at stock AFR's with no issues. My mileage is near what it was stock, around 45-46mpg on the backroads, a bit higher in summer but lower in city riding. It's hard to determine your mileage using a miles-per-tank description, as it all depends on the exact amount of gas you used referenced to total miles.

You probably are still running closed-loop with your setup, and if so I would assume the tuner set the Lambda table to .98 in the cruise range, which is the richest value possible for closed-loop. That wouldn't be much richer than stock and should realize better than a 20% drop in gas mileage. OTOH if he set yours to open-loop (O2 sensors disabled) by setting Lambda <.98 there is an almost infinite range of AFR options, and if that's the case you could be running considerably rather than marginally richer than stock.

I would take the bike back and ask them how they tuned your bike, then get back to us, and a screen shot of the Lambda table would be revealing. You might ask them your options for setting the cruise range for better mileage. I would not want to mess with a good tune at WOT, as you need maximum power when it is required, and since you aren't in that range often (are you?) it wouldn't affect mileage significantly.

Yes, it's possible, but more likely the tuner just has a different idea of the best compromise for mileage and cooling. It may be time for a tweak to get mileage in line.

IMO it wouldn't affect mileage significantly, all other factors being equal. It is more displacement but compression is higher, which I think would more-or-less cancel-out each other.

No, not more efficient but equally good, IMO, given a good human tuner. You can get an excellent tune with the PCV or a good "canned" map. If you had not yet made a tuner purchase it would be a good option, but it makes no sense to change tuners when you have a perfectly good device installed already. The limitation is in the human factor and the tune itself, not the device.

That said, I am not saying the tuner provided you with a poor tune, but it may simply require a reassessment of your needs. I would discuss it with them.

I have an '07 TC96 with 255 cams, AC, Jackpot mufflers, and a Power Vision with a very good self-tune (IMO). Power is excellent with no flat-spots and my mileage is in the mid-40's in winter, approaching high-40's in summer, and high-30's in city riding. You should be able to get close to that. I'm running Lambda 1.0 (14.6:1 AFR) in the cruise range, which is leaner than most prefer, but my bike does not run hot or have an negative effects from running these stock AFR's--and yours shouldn't either. An oil cooler helps in keeping oil temps in control, so if you don't have one it should be high on your to-do short list.