Your MPG please

[spacetiger]

Thanks for the reply. Here's some more info:

The pipes are wrapped, I had Lou at Pirate Powersports do it so it would get done right. He put heat shielding all inside it too, and also did my first full service so I know he checked for leaks and bad hoses. I use 91 octane fuel, but I'm in California and I know everything has ethanol in it. I do often get a strong gas smell from the bike, at odd times and without any pattern to pinpoint why. Also, I just walked out to the garage and wiped the insides of the exhausts with a clean paper towel, and there is almost no soot (much to my surprise).

:banghead:

okay, let say for now, the tail pipe wipe is telling us you are not dumping excess fuel into the engine. I don't know what A/F ratio we run stock, but lets just say it averages out at 14:1 (I'd guess we actually run at a lower ratio, say 13:1 on the avg). For you to be running 50% under the average mpg (~ 30 mpg), your F/A ratio would be running under 10:1 (maybe close to 9:1). I would think constant running at that level would soot up your pipe for sure.

So, where is the gas going? Are you able to pull the left side panel off and run the bike a few days with it off? This allows you easy access to the gas tank via the exhaust pipe side. I was curious what is the ride duration to and from work (curious how long it takes to run down ~6 gals)? Is it possible to ride to work and feel the gas tank after getting there? I think you can get these stick on temp gauges used to take your temperature. You pop them on the forehead and watch where the temp tops out. These or an IR temp gun could be used to see how hot your gas tank is getting on these rides if you don't want to use your hands. If you do do this, make sure all the other panels are held on with their fasteners so nothing goes flying off. With the panels off, it might make it easier to you to pin point the source of the gas smell.

Have you made any mods to the bike; exhaust, intake, ignition...?

Jerry

Edit: Watch this youtube experiment on the boiling temp of gasoline - then use your imagination on what is happening inside you gas tank with the exhaust pipe next to it. There is a comment posted and have heard this before: "The higher the octane level of the gasoline, the lower the boiling temperature the gasoline will have. The highest octane level gasoline boils at 100 degrees Fahrenheit. The lowest octane gasoline boils at around 400 degrees Fahrenheit"/ So, you say you run 91 octane and I see you live in 29 Palms (hot)... perhaps you have a unique situation of a lot of heat all the time, perhaps a lot on long commuting rides and run higher octane gas... Maybe you are just boiling it off? Try running a few tanks of 87 and see what you can do to drop the temp of the gas tank 10% (assuming you can measure the temp it runs at) :
http://www.youtube.com/watch?v=d7AkcjnCTVU

 

[NancysToy]

The first question that comes to my mind is "How are you calculating your gas mileage?" I know that sounds silly, but there are people who don't do it correctly. Just as a refresher, to calculate mileage you fill the tank consistently to the same level, and divide the miles traveled between fills by the amount of fuel used. The trip odometer is handy for recording the miles...reset it at each fill. Fill slowly with the nozzle just inserted into the tank an inch or less. Stop when the nozzle clicks off...or at least the second time it does so. At 22 mpg you would only get about 100 miles between fill-up and the low fuel light. That may be considered normal by BRP (I was told they accept down to 16 mpg as "normal"), but it indicates a problem to me unless you are constantly riding at 80 mph or above, or are burning the rear tire from every stoplight. Having the windshield fully raised all the time will knock off a couple of mpg. Even with the large amounts of ethanol in our gas here, our relatively low altitude, and seasonal gas formulations, I have gotten an average of 28+ over 25,000 miles...much of it two-up and pulling a trailer at freeway speeds. Many do better than that. I almost never raise the windshield more than an inch.

One of the most common ways to drop your mileage is ignition problems. A bad plug wire is almost always good to put your mileage in the low 20s consistently, as is a fouled spark plug. Those would be good things to check. Bad wires will make arcing noises and show spark jump with the body panels off in a darkened garage. A set of BajaRon plug wires and plugs would be a good cure. Other possibilities would include the coil, ECM, or a sensor problem...less likely, but certiainly strong contenders. Techs (and service advisors) are often reluctant to chase fuel mileage issues. Mileage is so variable that they have little to go on. Keeping careful fill and mileage records may help convince them. A box of donuts and some frank conversation can't hurt. If you can get their curiousity aroused, and gain a sympathetic ear, they can often ferret out the problem. Saying "If I can't get better mileage and range than this, I may have to sell my Spyder," is sometimes a way to get their attention. Best of luck in your quest.

 

[Magdave]

okay, let say for now, the tail pipe wipe is telling us you are not dumping excess fuel into the engine. I don't know what A/F ratio we run stock, but lets just say it averages out at 14:1 (I'd guess we actually run at a lower ratio, say 13:1 on the avg). For you to be running 50% under the average mpg (~ 30 mpg), your F/A ratio would be running under 10:1 (maybe close to 9:1). I would think constant running at that level would soot up your pipe for sure.

So, where is the gas going? Are you able to pull the left side panel off and run the bike a few days with it off? This allows you easy access to the gas tank via the exhaust pipe side. I was curious what is the ride duration to and from work (curious how long it takes to run down ~6 gals)? Is it possible to ride to work and feel the gas tank after getting there? I think you can get these stick on temp gauges used to take your temperature. You pop them on the forehead and watch where the temp tops out. These or an IR temp gun could be used to see how hot your gas tank is getting on these rides if you don't want to use your hands. If you do do this, make sure all the other panels are held on with their fasteners so nothing goes flying off. With the panels off, it might make it easier to you to pin point the source of the gas smell.

Have you made any mods to the bike; exhaust, intake, ignition...?

Jerry

Edit: Watch this youtube experiment on the boiling temp of gasoline - then use your imagination on what is happening inside you gas tank with the exhaust pipe next to it. There is a comment posted and have heard this before: "The higher the octane level of the gasoline, the lower the boiling temperature the gasoline will have. The highest octane level gasoline boils at 100 degrees Fahrenheit. The lowest octane gasoline boils at around 400 degrees Fahrenheit"/ So, you say you run 91 octane and I see you live in 29 Palms (hot)... perhaps you have a unique situation of a lot of heat all the time, perhaps a lot on long commuting rides and run higher octane gas... Maybe you are just boiling it off? Try running a few tanks of 87 and see what you can do to drop the temp of the gas tank 10% (assuming you can measure the temp it runs at) :
http://www.youtube.com/watch?v=d7AkcjnCTVU

Very interesting seems 160+ is the temp it starts to boil that answers a lot of questions in my mind. I and others have had 150+deg gas caps and heard boiling gas. I am guessing that may be part of the canister fume/drip problem after shut down. Thanks for the link.

 

[spacetiger]

Very interesting seems 160+ is the temp it starts to boil that answers a lot of questions in my mind. I and others have had 150+deg gas caps and heard boiling gas. I am guessing that may be part of the canister fume/drip problem after shut down. Thanks for the link.

What would be interesting to have seen was him measuring a specific amount of fuel (by weight or volume), then running the experiment he did. Then, you start timing in hour intervals once the gas starts boiling, how much is lost per hour at a given temp. Doing this experiment several times and vary the temp could probably give you a good idea of how much gas you can loose under high temp conditions.

I think you could apply this "data curve" (gas loss/hr vs temp) to what happens to the gas in our tank. All you need is a good temp gauge attached to the gas tank. I personally don't think its a huge amount, but it is enough to be noticeable, perhaps 5% - 10%?

If you ride short distances, 15 mi (~20 min), I would guess that is enough to get everything nice and warm then park the bike and go to work. The experiment shows the gas continues to boil after the heat is removed. Then, later in the day, you ride home and everything repeats. Live in a hot area, then the thermal soak period is extended, that is, it take the gas tank a very long time to cool down below the boiling temp for gas. In fact, it might not cool down very much [gas tank] if your bike is parked outside in the sun. I suppose the less gas there is in the tank means it gets to the boiling point faster as the heat load would be a constant. Throw in the fact that you use 91 octane with a lower boiling point (it goes even faster if you are using a winter gas blend), so your boiling time is longer. It would be difficult to estimate that loss without a calibrated test. Still, I'm not totally convinced it could account for a 50% loss rate over above the general mpg spyder population.

Like I said, if you could run 87 octane and keep your gas tank full (top off every day, make sure you top off the tank the same way every day so you know how much gas you use vs the miles driven). if you rode 30 miles a day, at your old burn rate that would be 1.5 gal. If you filled up every day just before you got to work, you would be adding 1 to 1.5 gals of cooler gas to 5.1 to 5.6 hot gas in the tank. That amount might be enough to cool the gas below its boiling temp (especially if you are running 87 octane fuel with a higher boiling temp). Its not a forever experiment, only a week. It should be an interesting experiment for us all to watch. Post back with the results if you do it.

Jerry

 

[Dragonrider]

2009 RS SM5 - windshield, hard bags, 295# - 6'4" rider, riding like I stole it all the time - 36.6 over 7,311 miles. High 42 mpg, low 28.8.
2010 RTS SE5 - Same rider, with more 2 up riding (my SO is 180 - 5' 11") - saner riding - 24.9 for the first 4688 miles, then 35.9 for the next 3280 (after CAT removal and YOSH add). High 52.1, low 18.8

In both cases, I went out of my way to use non-etoh gas. Record lows in both cases were Touring loaded, pushing through mountain twisties.

By comparison, my K1200LT delivered 52.3 MPG in 24,890 miles, and my Valks (3 of them) delivered 35.6 MPG in 137,988 miles.

 

[spacetiger]

3 things popped out to me in your post,
- mpg change after cat removal/muffler change for the RT-S
- you living in a cooler climate OR
- use of straight gas

It would be interesting to see how much cooler the bike runs without the cat and a free flowing muffler to keep the exhaust velocity up. I'm sure there is something out there that talks to the heat build up when you slow down the exhaust gas flow.

Jerry

 

[Daisyjoe]

2013 RT-S (semi auto)

In Town: 26 mpg
Country Side 27 mpg
Super Slab 29 mpg

Chris

This is in line with my 2013 RTS SE. I average 28 mpg. On my 2010 RS SE5, I average around 32 mpg.

 

[Bob Denman]

Your right wrist WILL have an effect...
What speeds do you normally run on the slabs??

 

[spyderbirds]

2010 RT A&C average of 30.77 over 34K miles

 

[R FUN]

I have a 2012 RT Limited, ride 2 up consistent, mostly 60 to 65 mph,in 5th gear a little over 4,000 rpm, bike has 13,000 miles always us 87 octane fuel, never had a single issue with bike. I get a consistent 37 to 40 mpg on U.S. gallon. I go between 160 to 200 miles between fills and seldom see the low fuel light.
My travel buddy ( same bike, same color) never gets as good a millage even traveling together. It appears something like the 2013 heat issue, some do some don"t . Go figure.
Roger

 

[jaherbst]

I don't understand how people are getting such good mileage. I have a 2013 RT with 1500 miles on it and I'm tracking my mileage with a fuel app on my phone at every fill up. I get 20-22 miles per gallon, if I'm lucky. I'm almost 6 ft tall and weigh 210 lbs, and I usually ride alone on flat desert roads, to and from work. I also ride rather normally. I can only go about 85 miles before the fuel warning light comes on and I have 1-2 bars left on my fuel gauge. I decided to put this to the test one day see if it was truly accurate... well I ran out of gas at 128 on the odometer. That's actually just a little less than 20 mpg. I had a gas can with me (thankfully) so I stood on the side of the road and added it so I could get to the gas station and fill back up. My plans on making this Spyder a long distance vacation touring bike for myself and the wife are pretty much gone....yep.

Something is very wrong. I am 240# and my wife is 150#. Out of the box we get between 30-33. Have the dealer check this. Fuel injecter nozzles (clean) newplugs, brakes (dragging) bad bearing, tire pressure too low, I could go on but check these first. Hook it up to BUDS and see if you show any fault codes. (dealer)

 

[jaherbst]

Well the wife and I rode for most of the day and we had to fill up twice. What I don't understand is that on the digital gauge I was on my last fuel bar when the low fuel light came on, but the tank only took 4.4 gallons at the pump. So if I still had 2+ gallons in the tank, why is it showing I'm almost out? Regardless, after highway driving the average was exactly 24 mpg according to my Gas Cubby app. Another thing that I find odd is that if my digital fuel gauge is correct, I lose 1 bar every 17 miles. So by the time I'm down to 2 bars left and the low fuel light comes on, I've traveled less than 120 and I'm stressing to find another gas station.Not cool.

Forget the app. Try it the old fashion way- miles divided by gallons equals MPG. Almost all gas gages have a mind of there own. Get a one gallon can, take it with you and drive (on a two lane highway) until you run out. Check the odometer that you zeroed when you filled up with gas. Divide the miles ridden by 5.5--5.8 and that will be your miles per gallon. Now the important part: Put the 1 gallon of fuel in that you brought along, start up and head to the nearest gas station and fill up. Always zero both A an B miles driven each time you fill up. Forget the app. and the fuel gages unless after this test you find they are right on the money. After over 125 motorcycles, both antiques and new, I always use the miles driven and factor in on the conservative side the wind, terrain, traffic and city driving. Fuel gages are not very accurate. Period.

 

[Empty Pockets]

28 to 30 mpg is pretty normal for my RTS SE5. Mpg falls off quickly if you are cruising at 81mph I've seen it as low as 23.5mpg cruising at 81 into a 15 to 20 mph head wind.

 

[jaherbst]

I shift at 5500 RPMs. I'm a bit OCD about it too.I never ride in a gear that puts the RPMs below 4500. I only get to 5th gear on the highway at speeds above 60. I also drive in trailer mode, so it won't even let me upshift until I've passed 4500 RPMs and it downshifts at 3500 RPMs. My riding style was developed after reading a lot of input here, specifically this post:http://www.spyderlovers.com/forums/...-for-new-Spyder-owners&highlight=cruise+shift

After reading further I think driving in " trailer mode" is your problem. Don't do it unless you are pulling a trailer. Trailer mode only allows shift up at a higher rpm. It also dowwnshifts at a higher RPM to allow some engine braking due to the increased weight of the trailer. It always keeps the RPM higher to prevent lugging and possible engine damage. If you are not pulling a trailer you should never be in "TRAILER MODE" unless you want to just burn more gas. Take it off and I will guarantee your gas mileage will improve. Sorry about the other posts but did not read all before replying. Some one gave you some bad information.

 

[stevedfive]

On the first fill-up of my 2014 RTS, I got 36.5 mpg.

 

[Dat Guy]

I'm going to try several of the options I've seen here over this next week and I'll report back with results when I get them. :thumbup:

 

[Jeriatric]

Just in from a thousand mile round. 25 mpg was the lowest mpg, with 29.x being the best. Hills, head winds, tail winds, twist and turns. Highway speeds were never under 70 and a couple hundred were 80+ on cruise control. Bottom line. I didn't buy a spyder for gas mileage. I bought it for the smiles it gives me. The K1600 I was running with got excellent mileage but, it's missing one wheel and isn't the width of a box car. That said, the K1600 driver is thoroughly impressed with the spyders performance. And he's a rider. The 1600 is just over 2 yrs old and has over 65K on it. Gas mileage? Give me...rider smileage - thank you.

 

[Bob Ledford]

2011 RTL SE-5

25 in town
26/27 mixed
30 hi way

 

[ChrisW]

On the first fill-up of my 2014 RTS, I got 36.5 mpg.

The wife is looking at the new RTS auto in yellow or white, How do you like yours ? where did you get it and did you test ride one first?
Thanks,
Chris & Sandy
Yuma, AZ.