Fuel economy is terrible!!

Update...

Had the thermostat changed. No difference. Original thermostat was not stuck.

My motorbike takes 2min15sec to get to one bar (this was at ambient temperature showing 18C), 2min45sec to get to 2 bars, and 4min25sec to get to 3 bars on the temperature gauge.

The bike "choke" idle (cold idle) is about 2000rpm, then goes down to 1000rpm when warmed fully.

Can a too-rich mixture keep the motorbike cooler (and hence warm up more slowly)...??

The live data read-out I had performed showed all sensors normal and "within spec", but one thing that caught my attention was the O2 sensors showing different voltages (more than 20% difference). First sensor showing .449v, O2 sensor B showing .566v. I have no idea if this is standard or irregular. More knowledge is welcome if anyone has knowledge to share.

There were 2 error codes, but these seem likely to have occurred from the throttle body vacuum check that I had performed.

2-1 Map sensor no vacuum.
9-2 IAT sensor voltage high. (Would this error code also be due to vacuum check of the throttle bodies...??)

My most recent fuel economy check (distance corrected via GPS tracker) is 14.8km/l, or 34.81 US mpg. This is 85 percent highway driving anywhere from 70kph to 120kph.

Perhaps fuel and cold, damp, and salty air environment here just make this bike a gas pig on the east coast... I just saw a car specialist on youtube mention he was getting 36mpg from his Toyota Matrix on the highway at 70mph. I find it hard to believe that this 1.261 litre engine motorcycle can't even beat a friggin Toyota Matrix for gas mileage...

I'm hoping to go on a road trip soon, and I don't want to have to refuel after only 350km... Seems silly, since every review I read about this bike stated one of its advantages is you can drive for 450to500km on a tank...


I typically ride about 365km between fill ups. I like to leave a couple of gallons in the tank just in case.

Did you see them change the thermostat?

It would be interesting to remove the air filter on your bike and see what the KPG is.

I have literally lost count of the number of times a shop has claimed to have done a job and done absolutely nothing. Sometimes making thousands of dollars on customers over a period of months, pretending to solve a problem.
 
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I typically ride about 365km between fill ups. I like to leave a couple of gallons in the tank just in case.

Did you see them change the thermostat?

It would be interesting to remove the air filter on your bike and see what the KPG is.

I have literally lost count of the number of times a shop has claimed to have done a job and done absolutely nothing. Sometimes making thousands of dollars on customers over a period of months, pretending to solve a problem.
They changed it. I have the old one. And they used my comment and have back the remaining litre or half litre. The fellow (Eric) reported original coolant looked very clean. No visible problems with chipping paint or corrosion were visible.

Thanks for posting your refuel interval. This is a good reference. Are you doing mostly highway or mixed with city?
 
They changed it. I have the old one. And they used my comment and have back the remaining litre or half litre. The fellow (Eric) reported original coolant looked very clean. No visible problems with chipping paint or corrosion were visible.

Thanks for posting your refuel interval. This is a good reference. Are you doing mostly highway or mixed with city?

Mostly highway. The only thing I do with cities is ride through them. I’m not a city guy.
 
I have ridden a lot in Nova Scotia and have never had my fuel efficiency change just because I was riding in Nova Scotia. My overall average fuel consumption for all riding types, conditions and locations from date of purchase is 19.6 Km/L, 5.1 L/100 KM, 55.5 MP/imperial gallon, 46.2 MP/US gallon. This varies up and down depending on conditions and riding style, but the average for any given trip always remains close to this overall average. The same is true for when I have ridden in Nova Scotia as well.

There are several people on this forum who live in Nova Scotia. Maybe ask for them to post what fuel mileage they are getting as a reference point for you to work with.

If you are certain that there are no cooling system problems and no engine problems (plugs, air filter, fault codes, vacuum leaks, plugged 5-way tee, low compression, etc.) what remains, assuming the problem isn't an overactive right-hand wrist, is to much rolling resistance. That can be tire inflation, alignment, wheel bearings, etc.. It often ends up being dragging brakes that have gone un-noticed and un-diagnosed.
 
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I have ridden a lot in Nova Scotia and have never had my fuel efficiency change just because I was riding in Nova Scotia. My overall average fuel consumption for all riding types, conditions and locations from date of purchase is 19.6 Km/L, 5.1 L/100 KM, 55.5 MP/imperial gallon, 46.2 MP/US gallon. This varies up and down depending on conditions and riding style, but the average for any given trip always remains close to this overall average. The same is true for when I have ridden in Nova Scotia as well.

There are several people on this forum who live in Nova Scotia. Maybe ask for them to post what fuel mileage they are getting as a reference point for you to work with.

If you are certain that there are no cooling system problems and no engine problems (plugs, air filter, fault codes, vacuum leaks, plugged 5-way tee, low compression, etc.) what remains, assuming the problem isn't an overactive right-hand wrist, is to much rolling resistance. That can be tire inflation, alignment, wheel bearings, etc.. It often ends up being dragging brakes that have gone un-noticed and un-diagnosed.

Thanks for this. It is really helpful.

So far, I have changed plugs (no difference), new air filter (old one was new and clean when I got it, so I'll use it for next change), fault codes seem fine (except I'm not sure about an IAT code that could have arisen when my local shop checked the vacuum), 5 way tee was checked (I didn't see it, but it was reported as clean/clear), valves were checked, thermostat changed (original is still good and not stuck), compression (I have no idea how to check this), I inflate my tires a bit more than 42 psi, brakes were checked and reported as fine/standard (but I really don't know).

Even if I drive like a total granny (ie: change gears at 2500rpm maximum and into 4th gear at 50kph in the city), the best I can get in the city is usually average about 12 to 13km/l, and if I drive above 85kph on the highway, my fuel economy tanks. If I drive at real cruising speed (110-120kph), I get about 15km/l. When I'm at 75 or 80kph on the flats, I can get instant read-outs of up to 20km/l and better when coasting/engine braking.

I do have the wind deflector kits, but I still think 100kph should yield me a better mileage than a Toyota Matrix (2.4litre engine and 3000lbs curb weight, compared to 1.261 litre engine with 750lb curb weight)... And in the city, there wouldn't be enough wind resistance for that to be a factor.

Maybe I'll have to check brakes myself... (2x pro shops checked them and said they're fine... With the ABS and the Shaft drive, I wouldn't expect these wheels to freely spin like a bicycle). But truth is, I've never worked on motorcycle or automotive brakes, and I get fear-paralysis with things I don't know about...
 
I did some research on IAT sensor. Hmmm... Sounds like a possibility...
I hope you are making some progress on your fuel mileage issues ? I just returned from a decently long trip of 500km to destination and the same for return. Getting started,, I already had about 40km on the clock and a cold start that morning, as I had fueled up the night before. There was a tail wind that worked mostly for me, and I hoped to make it without adding fuel. I rolled into a Toledo Sunoco with just over 540km on the clock. And refilling showed I had burned 24 liters in total,, so approx. 5 liters left onboard. This was way better than I expected. I had spent most of the trip at about 4500rpm on highways. So I was impressed,,, to get above 20km/L. Coming home,, I got off the beaten path,,, and had a ton of fun on the twistiest roads I could find. Winds were on the beam (sailor know what that means). And although I didn't get precise measures,,, but I rode further and harder,, and it would be about 17-18km/L. Still really good,,, all things considered. This was riding my 2012, ThunderSTruck,, which has a couple of aero mod's,,, but otherwise is pretty much stock. Btw,,, the bags were loaded with new to me bike parts, and I even had a new sporty shorty windscreen strapped on behind me,, which now looks and performs great on Blue STar ! (inspired by @Blackpearl). So I hope you find this report encouraging,,, that the ST13 is indeed capable of some really good numbers. It certainly earned it's Pan-euro stars on this trip,,, cheers,,, CAt'
 
I hope you are making some progress on your fuel mileage issues ? I just returned from a decently long trip of 500km to destination and the same for return. Getting started,, I already had about 40km on the clock and a cold start that morning, as I had fueled up the night before. There was a tail wind that worked mostly for me, and I hoped to make it without adding fuel. I rolled into a Toledo Sunoco with just over 540km on the clock. And refilling showed I had burned 24 liters in total,, so approx. 5 liters left onboard. This was way better than I expected. I had spent most of the trip at about 4500rpm on highways. So I was impressed,,, to get above 20km/L. Coming home,, I got off the beaten path,,, and had a ton of fun on the twistiest roads I could find. Winds were on the beam (sailor know what that means). And although I didn't get precise measures,,, but I rode further and harder,, and it would be about 17-18km/L. Still really good,,, all things considered. This was riding my 2012, ThunderSTruck,, which has a couple of aero mod's,,, but otherwise is pretty much stock. Btw,,, the bags were loaded with new to me bike parts, and I even had a new sporty shorty windscreen strapped on behind me,, which now looks and performs great on Blue STar ! (inspired by @Blackpearl). So I hope you find this report encouraging,,, that the ST13 is indeed capable of some really good numbers. It certainly earned it's Pan-euro stars on this trip,,, cheers,,, CAt'

@W0QNX
 
I hope you are making some progress on your fuel mileage issues ? I just returned from a decently long trip of 500km to destination and the same for return. Getting started,, I already had about 40km on the clock and a cold start that morning, as I had fueled up the night before. There was a tail wind that worked mostly for me, and I hoped to make it without adding fuel. I rolled into a Toledo Sunoco with just over 540km on the clock. And refilling showed I had burned 24 liters in total,, so approx. 5 liters left onboard. This was way better than I expected. I had spent most of the trip at about 4500rpm on highways. So I was impressed,,, to get above 20km/L. Coming home,, I got off the beaten path,,, and had a ton of fun on the twistiest roads I could find. Winds were on the beam (sailor know what that means). And although I didn't get precise measures,,, but I rode further and harder,, and it would be about 17-18km/L. Still really good,,, all things considered. This was riding my 2012, ThunderSTruck,, which has a couple of aero mod's,,, but otherwise is pretty much stock. Btw,,, the bags were loaded with new to me bike parts, and I even had a new sporty shorty windscreen strapped on behind me,, which now looks and performs great on Blue STar ! (inspired by @Blackpearl). So I hope you find this report encouraging,,, that the ST13 is indeed capable of some really good numbers. It certainly earned it's Pan-euro stars on this trip,,, cheers,,, CAt'

So, I've noticed when it's below 20C, the fuel mileage is not so great. And if I go about 90kph, the fuel mileage is usually quite good, but over 90 kph and fuel economy starts to tank. I can still get respectable average fuel economy at 110kph, but at 120 (which is my preferred cruising speed) the mileage goes to about 14km/l.

If you are at 4500rpm on highways, you're in 5th gear near 125/130kph... (unless your gearing is different than mine.)
 
If you are at 4500rpm on highways, you're in 5th gear near 125/130kph... (unless your gearing is different than mine.)
At that speed your going to suck gas. Triumph Trophy is a different animal but look how the MPG's change with speed
Manufactures spec, "The Trophy's efficient engine and tall 6th gear provides relaxed cruising and impressive economy with 69.2mpg at 56mph, and 54.5mpg at 75mph." Then look what it gets in real life. https://www.fuelly.com/motorcycle/triumph/trophy_se_abs/2015 big difference.
 
At that speed your going to suck gas. Triumph Trophy is a different animal but look how the MPG's change with speed
Manufactures spec, "The Trophy's efficient engine and tall 6th gear provides relaxed cruising and impressive economy with 69.2mpg at 56mph, and 54.5mpg at 75mph." Then look what it gets in real life. https://www.fuelly.com/motorcycle/triumph/trophy_se_abs/2015 big difference.

Interesting and good point! Thanks.
 
I was on the highway yesterday for a fairly long run and turned on my MPG gauge as I was curious. At 4500 rpms, I was near 85 mph and my read out was 39.6 mpg. I slowed to 75 and ran steady then checked again a few miles down the road and saw 44 mpg's :)
I didn't check it at 68 mph though, which is the speed limit there. :) At 75 mph, I was the slowest on that stretch of highway. :)
Maybe my choice of oil helped? lol
 
I slowed to 75 and ran steady then checked again a few miles down the road and saw 44 mpg's
About the same for me Kevin.

108 Kmh/67 mph true, 120 Kmh/75 mph indicated, is about where I am at 4,000 RPM.
I find that riding 4,000 RPM provides the best fuel efficiency while riding at a speed that I can safely get away with around here. Slower speed/lower RPM will return better fuel efficiency, but it is to slow to be comfortable or enjoyable. 4,000 RPM seems to be the sweet spot for a safe compromise between no speeding tickets and fuel efficiency.

My overall average since the motorcycle was new is 19.6 Km/L, 55.5 miles per imperial gallon, 46.2 miles per US gallon.
 
About the same for me Kevin.

108 Kmh/67 mph true, 120 Kmh/75 mph indicated, is about where I am at 4,000 RPM.
I find that riding 4,000 RPM provides the best fuel efficiency while riding at a speed that I can safely get away with around here. Slower speed/lower RPM will return better fuel efficiency, but it is to slow to be comfortable or enjoyable. 4,000 RPM seems to be the sweet spot for a safe compromise between no speeding tickets and fuel efficiency.

My overall average since the motorcycle was new is 19.6 Km/L, 55.5 miles per imperial gallon, 46.2 miles per US gallon.

My speedo reads true, odo reads 6km/100km low. I've checked this many times, so my posted results reflect the true adjusted results. At 120kph, my tach reads 4300rpm. This bike's engine loses fuel efficiency above 3500rpm. I want a 6th gear. It's power/torque curve certainly has enough in it to cruise at 120kph at 3500rpm. Honda bikes are geared VERY short. My 2003 honda shadow 750 was screaming in rpm's at 100kph until I changed sprocket size, then had a custom belt drive kit with custom ratio. That settled it down. I'm presently engaged with a specialty automotive gear maker to see about getting custom final drive gears made to lower rpm approximately 15%. This would take 120kph cruise from 4300rpm down to 3650rpm. I guarantee fuel efficiency will improve, and in-town riding will improve as well. 1st gear is so short that I gotta change into second IMMEDIATELY...!! And a few times I've forgotten to switch to 1st and I can still start fine in 2nd (except on an up-slope). The bike could actually use 20% taller gearing, but I wouldn't want to put that extra 20% all in the final drive.
 
I was on the highway yesterday for a fairly long run and turned on my MPG gauge as I was curious. At 4500 rpms, I was near 85 mph and my read out was 39.6 mpg. I slowed to 75 and ran steady then checked again a few miles down the road and saw 44 mpg's :)
I didn't check it at 68 mph though, which is the speed limit there. :) At 75 mph, I was the slowest on that stretch of highway. :)
Maybe my choice of oil helped? lol

If I'm at 85mp, I'm more like 4750 rpm and my mileage SUCKS at this speed. (Sure, wind resistance yadayadayada, but cars with larger engines get better mileage. It's a gearing issue for sure!!!) I have a "speedo healer" installed and my speedo runs true. If you have no speedo healer, you are probably showing about 5% lower than true speed, so 85mph on a non-corrected speedo would be 80.75mph.

My mpg results are adjusted to "real" based upon the 6km/100km deficit in odo reading, so I do my calculations with gas consumption manually. I get about 13.5+- km/l showing on my on-board gauge, which works out to about 33.6mpg. Pretty crappy IMHO. This bike NEEDS a 6th gear or even better, TALLER GEARING.

Take a peek at my response above and my shadow 750 experience.
 
This bike's engine loses fuel efficiency above 3500rpm. I want a 6th gear.
There is something that is causing your increased fuel consumption. It is not the gear ratios. Every ST1300 has the same gear ratios and they all consume much less fuel than what you are reporting. You can change gears ratios if you like, but it should be because you want lower RPM, not to fix your fuel consumption problem as that is treating the symptom. The cause of the increased fuel consumption needs to be found and dealt with.
If you have no speedo healer, you are probably showing about 5% lower than true speed, so 85mph on a non-corrected speedo would be 80.75mph.
The wording is backwards but the example is correct. With no speedo healer the factory ST1300 speedometer indicates higher than true speed, not lower.
Most people report that it reads in the 7% higher range.
 
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Lets go back to you earlier readings with the oxygen sensors, start looking for a vacuum leak. Put a vacuum gauge on the intake and see what the reading is, Try switching the sensors to the opposite side. The other thing that is worth checking is to pull the plugs and re-inspecting, they will show either rich or lean. Rich or lean both will ruin fuel economy.
Some of the manufactures have been quietly known to adjust the speedo to run out the warranty sooner. But that opens up a discussion that does not pertain to mileage issues. Just thought I would throw that in for fun.
Remember KISS....Keep it simple and start at the basics, What effects fuel air ratio if none of the sensors or codes show and one of the main ones I have commonly seen is unmetered air on the intake side.
 
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