I have a 2011 Road Glide Ultra with a CSC F1SE. I ran a mileage check for a measured run. On the way to I rode 6th gear at 72 mph. Got 21 mpg. Way back I rode 72 in 5th gear and got over 31 mpg. Now I am confused. I live in Florida, so hills are not an issue. Wind was same both ways (against me, as usual) so that is even. Is this a normal fuel problem? Without a car I got 41 or so, with car in 5th gear I am down to 30. Is this normal and how can I improve this? I am going on a 1000 mile round trip in September and want to get better gas mileage than my car. What will happen when I put a car tire on? Will it improve?
I get about .35 with my 1300 VTX with my Escort, but it is only a 5 speed. On a long trip (SC to Daytona HD) I got closer to 37.
I'm guessing that is about as good as you are going to get. Traveling in 6th I guess, is a fuel mileage no-no. I have heard several Harley riders say they rarely use 6th.
I hope you can improve that over time.
I pretty much keep my speed down around 62-65 on my VTX, pushing that brick through the air creates drag, as well as some lateral pressure on the drive wheel.
The laws of physics have not changed.
I have not noticed any significant variance since I put a car tire on my bike, accept much longer distance between tire changes
Doc
As Doc says in other words. A rig has the aerodynamics of an open parachute...
Beside every engine has its optimum runing point (revs / gas position/ torque / power => gas consumption).
When you have no down gearing in the final drive (sprokets or car tire) then you run probably in 6th gear at too low revs and the engine is not in its optimum working point. Probably you have to twist the gas more because you pull out a lot of torque at a point where the engine has not enough power.
Don't worry that is typical for HD riders and truck drivers or people like me, who grew up with tractors and longstroke engines...
So you have to learn to "listen to your engine" What is the right gear and gas dosification.
Or you gear down for sidecar relation.
Remember your bike was designed for solo riding.=> so gear/shift down so you get into the optimal engine working parameters again.
2 Cent from Costa Rica.
Sven
PS: Look who opens his mouth! 10 days ago I blew my Jawa 350 engine trying to cross the Cordillera. :O :o:(
Lsquid - 7/18/2012 5:43 PM
I have a 2011 Road Glide Ultra with a CSC F1SE. I ran a mileage check for a measured run. On the way to I rode 6th gear at 72 mph. Got 21 mpg. Way back I rode 72 in 5th gear and got over 31 mpg. Now I am confused. I live in Florida, so hills are not an issue. Wind was same both ways (against me, as usual) so that is even. Is this a normal fuel problem? Without a car I got 41 or so, with car in 5th gear I am down to 30. Is this normal and how can I improve this? I am going on a 1000 mile round trip in September and want to get better gas mileage than my car. What will happen when I put a car tire on? Will it improve?
Are there any modifications to the machine? Cams, Stage modications, pipes? Sometimes changes can affect fuell mileage. When I had my 2004 Ultra with a Harley sidecar, I would get no less than 35 mpg. That was an 88 cubic inch engine. Generally, a late model Harley will get better wileage than 21 with a sidecar.
The issue of 6th gear versus 5th gear is the key when pulling a heavy sidecar. In fifth gear, you are 3.40 to 1 and in 6th gear yoiu are 2.8 to 1. 2.8 to 1 is simply too high a gear ratio for a sidecar rig like you have. With that gearing you are using more throttle to overcome the wind drag.
Since the fuel mileage is above 30 with fifth gear at 3.4 to one, that tells me that the ratio in fifth geat is best for your touring.
On my 2004 Ultra, the original gearing was 3.15 to 1 with five speeds. That was too high. I was able to change the gearing with different primary sprockets and lower it to 3.37 to 1, which was perfect for my rig.
So, you have two choices: either run in 5th gear or change the gearing which is very difficult on post-2006 Big Twins. You would have to change the rear belt ratio since there are no aftermarket parts available for the primary with the later design....at least I haven't seen any.
Good luck!
I've been told on 06 HD and older the cheepest way to change the gesr ratio is with clutch basket. There is two diffrewnt sprocket sizes. Now on 07 & 08 HD you need to change the Primary sprooket to 33 teeth. Reason being in 07 & 08 the rear sprooket is 66 thooth. 09 and newer it's 68 tooth. and can't interchang with older HD. I did the change on my 07 and oil cooler, wih sysn. oil. But when I ran a sidecar and pulled the Bunkhouse. I ran 5 th. and got 35 plus MPH. And everyone knows. I MOVE RIGHT ALONG IN MY TRAVELS. But I can follow other's at any speed. But I don't lead other worth a daron.Rudy
i find that if i ride under 60 i get 31+ - and if i ride at 80 i get 20+
at 80 6th gear seems ok most of the time but i run in 5th a lot. at slow speeds i run 6th if no headwind or hill, 5th the rest of the time
i really should run a couple of full tanks of gas in 5th and see if its better, if it is then a gearing change would be in order
the complicator is that 5th takes more energy to run since its not direct - if 5th gear was the exact same milage as 6th then a gear change would get better milage since 6th is direct.
hmm - a project, just what i need
also there are now new clutch baskets with more teeth [simple and not too expensive] - and hd sells tri glide sprockets with fewer teeth [dirt cheap actually] - the bugger is the speedo and cruise control - to make them work right with a gear change takes tts - thats a lot of tanks of gas to break even.
ill put a sticky on the dash this week to try and run 5th all the time [a week is 300 miles or so] and see what the milage works out to be.
to
There is no "rule" that you need to cruise in top gear. If fifth gear gives the best mileage at the speed you want to run, just stay in fifth gear. Save your gear ratio change money for gasoline.
George Ryals - 7/22/2012 3:27 PM
There is no "rule" that you need to cruise in top gear. If fifth gear gives the best mileage at the speed you want to run, just stay in fifth gear. Save your gear ratio change money for gasoline.
The only negative issue that I can see is that the late model Harley-Davidson six-speed transmissions have helically cut gear teeth in the speeds below sixth, which is direct drive. This will place greater stress on the thrust washers that are used to control end play in the transmission. Generally this is not a problem on a solo machine, since most riders won't stay in the lower gears for long periods on the road. On the other hand, the fifth gear ratio, at 3.4 to 1 is perfect for pulling a sidecar with the later 96" or 103" engines.
All in all, I'd probably run in fifth gear. I agree that it's better to use fifth gear and get the fuel mileage than spend hundreds of dollars on a major change of gearing, especially if you were to change the rear belt and pulleys. those jobs are really nasty.
when I ran my sidecar and trailer it pulled it alright in 6 th. but the engein just seamed labored so I just ran 5th. And got my 35 MPH which was better than when I tryed to run in 6 th. It just didn't fell right in 6 th. Now with the whole thing I ran around 70,75mph. Speed is not the main thing, you have got to be able to STOP. I don't linger in the service station get gas drink an use rest room and be gone, when i'm solow.RUDY
i tried to do some testing of milage vs gear
first - my y pipe has been found to be cracked and they wont fix it for a week or two - esp & sturgis coming so the shop is full, so i have to wait
second i did two tanks when it was over 90f in fifth - got 26
then i did two tanks in sixth and now the temps are more normal, 70's and got 28 and 31
so i cant tell if the temp is a factor? the y pipe crack is a factor? or the gear is the factor
on the two lane roads when its cold in 6th going 55 to 60 i get 31 to 33 in the past
more later
timo482 - 7/28/2012 6:40 AM
i tried to do some testing of milage vs gear
first - my y pipe has been found to be cracked and they wont fix it for a week or two - esp & sturgis coming so the shop is full, so i have to wait
second i did two tanks when it was over 90f in fifth - got 26
then i did two tanks in sixth and now the temps are more normal, 70's and got 28 and 31
so i cant tell if the temp is a factor? the y pipe crack is a factor? or the gear is the factor
on the two lane roads when its cold in 6th going 55 to 60 i get 31 to 33 in the past
more later
If this is a late model machine, the cracked Y-pipe could definitely affect mileage. Assuming that you have not modified the exhaust system, there are two exhaust gas sensors in the system, one in each header pipe. If there is a leak, it's possible that the system is going rich to compensate. 26 mpg is intolerable.
As to the Y pipe crack, that's almost universal on Harley FL's. They pretty much all do it on the rubber mouinted engines all the way back to the 1982 FLT's. The fix is to remove it and, after welding the basic crack, add a strap across the crack and weld it on as well. The area usually won't show and there are heat shields on the outside so it's no harm, no fault.
On my 2011 Dyna Street Bob, the engine is also rubber mounted but the exhaust is tied to the motor and transmission, not to the frame at the mufflers like the big FL's are. This is a design fault on the FL's that has not yet been corrected.
As to the Y pipe crack, that's almost universal on Harley FL's. They pretty much all do it on the rubber mouinted engines all the way back to the 1982 FLT's. The fix is to remove it and, after welding the basic crack, add a strap across the crack and weld it on as well. The area usually won't show and there are heat shields on the outside so it's no harm, no fault.
On my 2011 Dyna Street Bob, the engine is also rubber mounted but the exhaust is tied to the motor and transmission, not to the frame at the mufflers like the big FL's are. This is a design fault on the FL's that has not yet been corrected.
My buddies and I have been riding FL's since 1993. I have never seen a cracked Y pipe or even heard of this happening ?
My buddies and I have been riding FL's since 1993. I have never seen a cracked Y pipe or even heard of this happening ?
That's very unusual. I visit dealers frequently, both factory and independent and I've seen boxes full of cracked FL Y pipes. You guys must ride very slowly. LOL.
In any case, it's a common problem that is well known among Harley touring riders. Check on Google groups and you will see what I'm talking about. The one on my 1993 FLHS cracked at 15,000 miles. I welded it and it was fine after that.
By the way, sometimes they crack and don't open up all that much. It's possible that a bike could have a cracked Y pipe and you would never know it until you removed the exhaust for maintenance or some other purpose. That's how I discovered mine.
Exhaust cracks will open up under heat expansion and will shrink back to be unnoticable when the exhaust is cold. What isn't noticable with short hops can be a real bothersome rattle after a while on the road.
Lonnie
Most of the bikes I've been around are relatively low mileage ( less than 30K on the clock ). Maybe this is why none of us are seeing the problem ?
