So what is the consciences on the best MPH for the best MPG? I do not think I am getting anywhere near what I should be. Maybe I am going too fast....NAW!!! I have a Ultar Classic if it helps. Thanks, I am trying to get the bike dialed in before the ride to Sturgis.

 

The MPH doesn't really have anything to do with optimal MPG's. It is RPM's that make the difference in the top gear for maximum MPG's. And even then there are a multitude of variables that come into play: 1 vs. 2 riders; weight of riders; extra baggage/luggage; highway vs. city; plains vs. mountains; cruise control vs. start & stop; proper tire inflation; ad infinitum, ad nauseum...

However, if we gauge everything on a direct comparison, and you are looking to squeeze out the optimal MPG's -- despite any of these variables -- you should keep the bike around 2500 RPM, give or take a couple hundred, in top gear (5th or 6th -- depending on year of bike). That is the "sweet spot" with regard to maximizing your MPG's. And if you have synthetics, and not dino, then you'll increase it a little as well.

I have a 2005 Ultra with SERT, K & N, and Samson Rolled Thunder pipes. I ride 2-up about 50% of the time, and also split the trips 50% highway and 50% backroads. I average 34-35 mpg's around town, and 41-43 on the open road.

Hope that helps!

 

I agree with t, sort of. I have a 06 RG V&H true duals, Rinehart mufflers, PCIII, and SE stage 1 intake. On normal roads in Northern VA, maryland, and PA (read mostly rolling hills) I get about 42 on the highway. I ride solo mostly. Call me crazy but it seems my bike wants to run at 70MPH (3000 RPM). It might do better at 2500 RPM but really seems to hit a comfort zone at 3000. Just my thoughts.

 

With my 2006 RK Classic (bone stock intake and exhaust so far) 55 mph with no stops except for the next gas station is the best speed. I'll get upwards to 50 mpg riding at 55mph (single rider not much luggage), but around 43-45 mpg at 70 mph (same set up). Add my wife and a bag on the luggage rack and it's just a bit worse. Even with some stops/slowdowns/shiftdowns (i.e. riding down Hwy 17 and A1A to Daytona Beach) the slower speed is better on gas mileage.

With that said I get much worse gas mileage commuting to work (41-42 mpg) even though more than half of it is spent at 55 mph. The other half is in 3rd and 4th gear on a military post...

 

Scotty:

I agree with you about the 70 mph issue. In fact, what I have found in doing road trips is that the bike actually feels better, sounds better, and rides better at about 80 mph. It is like it reaches its perfect "harmonic convergence" at that speed. The engine is just a "hmmmmmmm" and wind buffeting is not bad. Any faster, and the wind starts to become an issue. Slower, and the engine sound is instrusive. But also at that speed, the MPG's drop a little bit...

Heck, I don't think there is a better feeling, as far as comfort on a bike, than with passenger (wife!) and full tour pack and bags, haulin' along the interstate at 80 mph with about 78 degrees and 30% humidity...

 

Good MPG...44-46, will be in 5th between 2000-2500, 50-60 MPH.

 

I cruise at a pretty moderate speed of 58 to 62 mph on my '03 Ultra Classic and get as high as 51 mpg.

 

Hmmm, so you would give up MPG for higher speeds. Doing 70 on the interstate will get you run over around here. I’ll just have to play with it and run some test. Thanks.

If my MPG does not get better, what could be the problem?

 

I hear ya about doing 70 mph on the Interstate. I can ride at those speeds but I prefer not to. I go to Houston at least twice a year and have to drive 70 and 80 sometimes just to keep from getting run over.

58 to 62 mph is my favorite speed. I quit getting in a hurry a long time ago and at these gas prices these days every little bit I can save helps.

 

Read a letter in the Enthusiast some time ago, a rider asked a tech question based on getting low on fuel, what is the best speed/rpm for maximum gas mileage. The tech answered that 52 mph is the optimum speed for maximum fuel mileage. About 2200 rpm I think.[8D]