When I started winter riding the 52+ mpg dropped to 42. I suspected that the engine was not getting up to temp and running rich. The same thing happened with My XR1200 and Buell Ulysses XB12XT. When I covered the oil cooler on them the mpg returned to normal.

I tried twice to cover the M8 cooler with tape but laying on the floor between bikes and not being agile at age 76, I did not get the job done. Today I got the car out of the way and was able to cover the cooler. It worked. I went a half hour and the DTE started raising. When I filled up latter the DTE showed 300 which would indicate the ecm was seeing a 50 mpg average. When I fill again it should be the final verification that it was running under operating temp.

The M8 pump sends some oil to the engine and some to the cooler. It is supposed to have a thermostat in the line to the cooler but riding temps in the teens and 20's it seems that it never reached 185 degrees to open.

 

that doesn't make sense..my fan assisted oil cooler comes on every time I ride, and been as low as in the 30's..I doubt they would have it activate if the oil temps aren't even reaching 185..another post said the MOCO said it activates when the head temp reaches 220...oh well, trust it's all working as designed and assume no design flaw..I guess

 

The opening value for a thermostat is not the same as the cooling fan setting when the oil is getting too hot. Two different functions and purpose.

 

Let me help you out here. If you cover your oil cooler and your engine temp goes up you either do not have a thermostat inline or you have a thermostat stuck open. Covering a cooler that is not circulating oil is an exercise in futility.

You need to find a competent tech to work on your bike.

 

By a $25,000 bike and worry about MPG. I don't get it.

 

I get that, but its not always about the money, its MPG and the next station. I lost an easy 50 miles to a tank, that means I have to pay that much more attention to fuel stops.

 

Winter blended gasoline gets as much as 8% fewer mpg. Worth considering. I always notice a loss of mpg with winter fuel.

 

I save from $1,200 to $1,600 on my annual fuel costs by keeping the mpg at the top level. In the past two years I exceeded 85,000 miles. I ride my bikes year around. In remote areas it can be critical such as the Alaskan Highway and many areas of the S.W.

That covers the costs of plates totally and most of the insurance costs. Some may not have thought about it but one on the best sensors to indicate how your engine is running is mpg. When breaking in a new motor each fill up with gain then at a certain point it will plateau. My experience with breaking in 29 H-D engines since 09 is that about 700+ miles the engine is worn in as the mpg improvement tapers off.

It will tell you when to clean the air filter. I have cleaned the filter and gone on a 4K ride that the mpg has dropped. Cleaned the filter and back up it went. Same with injectors. In some of the rural cross county rides that I do it is easy to fill up with stale gas and notice a drop in mpg. l carry a jug of Enron Techron and it restores the injector promptly.

Yes winter gas is 106,000 BTU's/gal and summer blend is 115,000 so there will be a drop in performance. Winter gas used to be 112,000 BTU's and was not that noticeable until it was lowered by EPA several years back.

Greg: Thank You for kind and considerate input. However Roger Guttridge a long time well known HD engine performance builder agrees with the situation that I had. He is a highly skilled HD service manager.

This is how I set up for Canadian haul roads.


Riding the North American Continent is much different than riding local.

 

wow, that's a pile of time and effort put into thinking about and managing fuel consumption..I just ride mine and don't worry about that stuff..time is more valuable than money to me anyway but to each his own

 

mjweb: A pile of time? You have a 6 gallon tank and fill up the DTE reads 300 miles. What amount of time does it take to understand that the EMC is showing an average of 50 mpg? Like one second or two at the most.

During the summer it was reading 312 to 336 which translates to 52 to 56 mpg. When the winter fuel came online it went to 300 per tank which is 50. When the temps went into the 20's and teen's it dropped to 38 to 42.

That does not take a rocket scientist to understand the the EMC is not reading a temperature sufficient to discontinue enriching the AFR. It equates to not turning off the choke on a carbureted bike.

I never had an issue with a Twin Cam. But as HD has reported in its press releases that the M8's exhaust temperature is 100 degrees less than a Twin Cam. The M8 is the coolest running engine that HD has put out.