2018+ Softail Models Breakout

M8 Fuel consumption?

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Old Dec 27, 2020 | 08:29 AM
  #41  
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Originally Posted by OrangeThunder
I have never gotten lower than 40mpg and a high of 49mpg highway. I drive 70 to 75 also. All stock except slipons. 2020 FXFBS 114.
Yes, I assume 34 mpg is still low, based on your numbers. Will check as people suggested here.


Originally Posted by FranBunnyFFXII
Have you tried flashing back to your stock tune and see what happens?
DKCustoms showed that you dont need a tune for a slip on swap and maybe not even for an aircleaner swap.

And I think it was Kevin Baxter who said one of the big indicators of a sumping problem is poor gas mileage. I'll have to look up the video to make sure, but you do have a 2019 model year before they put in the 2020 pump that's supposed to fix everything.
EDIT yeah here it is:
5 minutes 40 seconds
https://youtu.be/UZUfR4-_es4?t=340
Yes I did try the stock tune it’s the same thing, but that video is very interesting cause I had this loss of power and I even contacted dynojet support team to ask about the map and we tried to change but with no success except raising the throttle response. That could be the case I will have to check with the dealership.

Originally Posted by turbotom1052
Haven't had time to read all replies but I think thats VERY low. As mentioned a compression test or better yet a leak down test would be in order. Have you checked your oil level in crankcase? With that kind of fuel usage Id be concerned with fuel wash past the rings. Check for high oil level and the strong smell of gas in your oil.
yeah, lots of informative replies, one change is that I miss calculated the average of my mpg it’s 33,4 instead of 22-25 mpg that I wrote in the start of the post.

yeah I will check what you suggested and keep you updated so this can be useful for someone with similar issue.

thanks a lot mates that’s helpful
 

Last edited by Ramimator; Dec 27, 2020 at 11:06 AM.
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Old Dec 27, 2020 | 04:21 PM
  #42  
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Originally Posted by FranBunnyFFXII
Have you tried flashing back to your stock tune and see what happens?
DKCustoms showed that you dont need a tune for a slip on swap and maybe not even for an aircleaner swap.

And I think it was Kevin Baxter who said one of the big indicators of a sumping problem is poor gas mileage. I'll have to look up the video to make sure, but you do have a 2019 model year before they put in the 2020 pump that's supposed to fix everything.
EDIT yeah here it is:
5 minutes 40 seconds
https://youtu.be/UZUfR4-_es4?t=340
Originally Posted by turbotom1052
Haven't had time to read all replies but I think thats VERY low. As mentioned a compression test or better yet a leak down test would be in order. Have you checked your oil level in crankcase? With that kind of fuel usage Id be concerned with fuel wash past the rings. Check for high oil level and the strong smell of gas in your oil.
today I was checking the engine oil, cold, on the jiffy stand and there was no oil on the measurement, so I had to straighten the bike to have a read, I usually check it when it’s hot. I do remember that I had this with my sportster iron, that I got no reads if my motorcycle is on the jiffy stand, but I didn’t know that this happen with the new softails too. Anyway the oil smells a lot like gas and there was like a black powder substance at the top of the oil stick measurement.
 
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Old Dec 29, 2020 | 09:43 AM
  #43  
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[QUOTE=Ramimator;19624845]Yes, I assume 34 mpg is still low, based on your numbers. Will check as people suggested here.




Yes I did try the stock tune it’s the same thing, but that video is very interesting cause I had this loss of power and I even contacted dynojet support team to ask about the map and we tried to change but with no success except raising the throttle response. That could be the case I will have to check with the dealership.



yeah, lots of informative replies, one change is that I miss calculated the average of my mpg it’s 33,4 instead of 22-25 mpg that I wrote in the start of the post.

yeah I will check what you suggested and keep you updated so this can be useful for someone with similar issue.

thanks a lot mates that’s helpful[/QUOTE
]When calculating your miles per gallon are you doing it with an accurate speedometer? I found that my 2019 softail speedo was off by 3mph @ 65 mph indicated. I guess it also needs to be asked is if everyone else numbers that your comparing yourself too have been calculated by an accurate speedo? I calibrated mine to a GPS and verified it with a radar gun. Since then ive recorded pretty consistent 39 to 40 miles per gallon, riding pretty hard in the mountains, at reasonable altitudes.
 

Last edited by turbotom1052; Dec 29, 2020 at 09:47 AM.
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Old Dec 31, 2020 | 03:47 AM
  #44  
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2020 FXLR - Stage 1 with Heavy breather and Street Cannon.
Small country roads. Sometimes 4 ways roads. Rather cool driving.

No more than 4L/100Km = 58 mpg. Running only with 95 E5 (not E10) fuel.

Stage 1 was a plus for low revs. I stay more often on the 6th gear, now. Less consumption in my case.
 
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Old Jan 2, 2021 | 07:45 PM
  #45  
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Originally Posted by Breizh Rider
2020 FXLR - Stage 1 with Heavy breather and Street Cannon.
Small country roads. Sometimes 4 ways roads. Rather cool driving.

No more than 4L/100Km = 58 mpg. Running only with 95 E5 (not E10) fuel.

Stage 1 was a plus for low revs. I stay more often on the 6th gear, now. Less consumption in my case.
thanks a lot for the info sir ✌🏼


[QUOTE=turbotom1052;19628606]
Originally Posted by Ramimator
Yes, I assume 34 mpg is still low, based on your numbers. Will check as people suggested here.




Yes I did try the stock tune it’s the same thing, but that video is very interesting cause I had this loss of power and I even contacted dynojet support team to ask about the map and we tried to change but with no success except raising the throttle response. That could be the case I will have to check with the dealership.



yeah, lots of informative replies, one change is that I miss calculated the average of my mpg it’s 33,4 instead of 22-25 mpg that I wrote in the start of the post.

yeah I will check what you suggested and keep you updated so this can be useful for someone with similar issue.

thanks a lot mates that’s helpful[/QUOTE
]When calculating your miles per gallon are you doing it with an accurate speedometer? I found that my 2019 softail speedo was off by 3mph @ 65 mph indicated. I guess it also needs to be asked is if everyone else numbers that your comparing yourself too have been calculated by an accurate speedo? I calibrated mine to a GPS and verified it with a radar gun. Since then ive recorded pretty consistent 39 to 40 miles per gallon, riding pretty hard in the mountains, at reasonable altitudes.
I think your mileage is average and close to what everyone mentioned here.

thanks for your answer mate.

Anyway today after my ride, I thought I should check my engine oil, I clean the stick then retest but there is no oil on the mesure, no oil at all? And I get no oil warning or anything.

it never happened to me, that’s very strange, I am not sire if it’s related or not will contact a dealership next week to check with them.
 
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Old Jan 3, 2021 | 11:06 AM
  #46  
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Did you shut the engine off before or after you put it on the sidestand? Shut off upright, then onto stand and check oil.
 
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Old Jan 3, 2021 | 11:40 AM
  #47  
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Originally Posted by Mart
Did you shut the engine off before or after you put it on the sidestand? Shut off upright, then onto stand and check oil.
yes that’s what I exactly did, I shut off upright, then I checked on the stand. Maybe I should shut off and check on the stand? But I did check the oil before and I never had this issue, I was checking the oil while the bike is on the stand.
 
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Old Jan 3, 2021 | 05:10 PM
  #48  
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You're doing it the right way. How many miles since it was last topped up?
 
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Old Jan 9, 2021 | 09:20 AM
  #49  
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Originally Posted by Ramimator
Yes, I actually did 6 autotune sessions
6 autotune sessions sounds a bit excessive. Wondering if your starting point with your tune wasn't way off???
 

Last edited by turbotom1052; Jan 9, 2021 at 09:24 AM.
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