02-05-2018, 01:26 PM
(02-05-2018, 12:14 PM)Ulvetanna_imp Wrote:(02-05-2018, 10:58 AM)SportsterDoc_imp Wrote:(02-05-2018, 05:58 AM)Nortoon_imp Wrote: Honda Canada has just posted the specs for the 2018 CB1100 RS.
They state the fuel tank holds 16.8 liters.
I doubt Honda has made a different tank just for the Canadian 2017 CB1100 EX.
So I am going to assume the tank on my 2017 CB1100 EX holds 16.8 liters .... until I run out of gas on some lonely back road.
The real question is not what the tank will hold, filled up from dry, but what is usable capacity, before the fuel pump intake sucks air.
A carbed bke could be run dry.
Not so with EFI.
Be good to figure that the last 1/2 gallon or 2 liters may not be usable.
Fortunately the pickup tube is towards the rear of the tank, so there is more usable going uphill, versus downhill.
The real question is not what the tank will hold, filled up from dry, but what is usable capacity, before the fuel pump intake sucks air.
A carbed bke could be run dry.
Not so with EFI.
Be good to figure that the last 1/2 gallon or 2 liters may not be usable.
Fortunately the pickup tube is towards the rear of the tank, so there is more usable going uphill, versus downhill. I ran my 2015 ZX-10R dry and had to push it to a gas station.
Fired instantly after I gassed up.
So I believe the notion that a fuel-injected engine cannot/should not be run dry is, or has, become archaic. It definitely doesn't apply to that bike. So, why would it apply to any other bike? What exactly happens? Does the fuel pump lose its prime? I think not. Does all the dirt in the bottom of the tank get pumped into the fuel lines and clog the works? I doubt that.
Those were the reasons given in past decades for not running a FI automobile dry. I am pretty sure they do not apply any longer.
Dry or to the point that the pump would not function?
A carbed bike can run a tank dry...may need some sloshing around.
A fuel pump cannot suck the last drop out. Once it sucks air, it is done, it has "lost its prime" until refueled. Most pickup tubes are a bit above the tank bottom.
Is it good to run a pump dry? Might get a bit warm, but I did that routinely on a 1996 Ford F150 with dual tanks, commuting weekly from Flagstaff, AZ to Ventura County, CA for about 4 months.
Sold the truck to the manager of our controls department. He still has it and no fuel pump issues reported.
The point was simply that a pump has some limitations over gravity flow.
A pump is less likely to pickup any bottom of tank sediment. If it can pick up sediment, it will do so at anytime, regardless of fuel level.
(02-05-2018, 01:26 PM)EmptySea_imp Wrote: Seems like an awful lot of consternation about the capacity. Ride it until the fuel warning light goes on...then ride it some more...then ride it somewhere close to a gas station....then ride it a little bit more...until you're REALLY nervous about running out...then ride it into the station and fill it up. If it takes more than 14.6L, then the tank probably holds 16.8L. If it takes less than 14.6L, then at some later ride, do the same steps, but ride a few miles more, keeping in mind the total miles you recorded from ride #1 as a guide. You'll figure out the fuel capacity AND the tank mileage this way.
Of course, you can also, just run it dry during ride #1 and avoid ride #2 entirely, but then you'd be depriving yourself of an opportunity to ride.
Well, I had the same questions in November.
I have gone past the far left segment of the fuel gauge flashing.
Don't remember for sure, but think it took 3.6 gallons (3.9 tank).
But, I did that in town.
In Nevada, away from Lost Wages, there are some trips with 154 miles between fueling opportunities. Places where signs read "open range 100 miles"
So, to plan for a trip, it helps to do the math. If I get as low as 45 MPG, if 3.9 is fully usable (I am skeptical), then I could go 175 miles. No uphill, no headwind, 65 MPH or less, probably 54 MPG x 3.9 gallons = 210 miles...but I certainly would not want to count on that.
West on the Extraterrestrial Highway has many passes at 6,000+ feet, generally significant altitude gain, long stretches suitable to push the speed (less MPG), before reaching the ghost town of Warm Springs (no services)...so it is a matter of how much extra fuel should I carry...perhaps 2 quart cans of TruFuel?
Generally, I figure 46 MPG as my worst, so 2 quarts = 23 miles.
Pushing a 540 pound bike may be good exercise, but pushing along a two lane with no shoulder and a rocky drop off is not my idea of relaxing!