Increase Fuel Capacity

[denysp]

Good day everybody, I own a 1980 XS1100SF. And I can only go about 115km/72mi to one tank of gas. Now I believe that the tank is a 15Liter/4 Gal Tank. Id like to be able to go further. Any ideas other then taking a gas can with me?? Any good aftermarket parts, different tank? Thanks for the help.

[beechfront]

when is your low fuel light coming on?

on mine speed makes all the difference in the world on my gas mileage.

i commute to work 100 miles round trip every day, and have two different routes.

route 1 - Interstate 80, speed limit 75mph. i drive 80mph and get around 30 mpg. low fuel will come on around 80 miles or so.

route 2 - highway 6, speed limit 60mph. i drive around 62mph and get around 40 mpg. low fule light comes on around 120 miles.

this is pretty consistent with other reports i've read on here.


if you are using too much fuel i think it means you are running too rich. do you have a stock configuration?

hope this helps.

[denysp]

Stock as far as I know, the carbs just got cleaned and tuned. I just bought the bike from my father, it runs like a pig at 3000rpm like its flooding itself.

I dont really know much about bikes and engines... its my first bike..

I get the low fuel lite on at about 115km or 120km

[MAXIMAN]

I think you have a problem. That bike should be getting better mileage.

Every Eleven Special I've had and every Eleven Special I've been around will go to 100 miles before the low fuel light comes on and that's cruising 80 mph. They'll pretty much get 33-34 consistently on long road trips at that speed.

However Beechfront is right. If ya slow down they get WAAAAY better. Last year I rode Big Bend National Park. Going down there at 85 mph Zilla was getting 33 to 36 mpg. When we entered the park the speed limit was 45 mph. We drove 126 miles through the park averaging 50 mph.

WOW WOW WOW....my fuel mileage on that tank jumped to 48 mpg!!! After 126 miles of boringly slow riding my tank only held 2.6 gallons.

[Ken Talbot]

dennysp - when you get your special in proper tune, it should deliver a pretty consistent 40mpg (imperial gallon). Tsunami used to be a bit of a gas hog too, but at least it has the biggest tank available. The single biggest difference I got was when I adjusted my float level by about 2mm from where it had been set. This lowered the fuel level in the float bowls and made a huge difference.

You say your ride seems to ride like a pig at 3k, loke it is flooding itself. That in fact may be the problem, especially if somebody has rebuilt the carbs and put in some after-market jets. Many guys have done this, only to find that the numbering system on the jets they installed bears no resemblance to the numbering used on the Mikuni jets. They put in the number they think should be correct, only to find it is way too big and causes an overly rich running condition.

You need to do a bit of work getting the jetting right, the floats set, and everything tuned up properly, Then, you should be able to get at least 180 km between fill-ups.

[TopCatGr58]

Hey Dennysp,

Aside from the carb problems, has the AIR FILTER been changed, cause it can choke things down badly as well if clogged/dirty!

You need to look at the VIN # and check the tech tips to verify what bike you have, cause the SF was the 79 model, and there is a big difference in the 78-79 series carbs vs. the 80-81 carbs!

If you are planning on keeping this bike and really enjoying it, then you will want to get a manual and get your hands dirty and learn how to work on them, they aren't as complicated as people make them out to be!!

Other problems like vacuum leaks, poor electrical connections causing poor ignition performance, clogged exhaust pipes/mufflers, etc.!?
T.C.

[denysp]

Thanks for all the comments I will see what I can find out..

Couple of things that I will check.. The VIN number for the proper model, lol

As for the comment about the electrical, the previous owner to my father removed the fuse box and put in-line fuse's. So There could be electrical issues.

I do have a clymers manual already and will have to do some learning about this bike..

[Winterhawk]

My 1978 XS1100E gets 38.6 MPG and if I ride it hard 36.4 MPG

Make sure your jets are the right size. Use a drill bit to check them. Some aftermarket jets are made wrong.

Check your fuel level and float height also.

Install a K@N filter.

The Jardine crisscross 4 into2's are really nice and mine goes 0 to 60 in 3 or 4 seconds. Still quiet also.

[LoserShoes]

Where did you get the pipes? YammerHammer is going to need pipes soon, and those look like the ones.

Steve

[John]

Pipes

Those criss-cross pipes are cool, huh? I have them on my bike also, but I had to but a parts bike to get them. If anybody knows of a spare right side muffler for these pipes, I'd appreciate it. Mine was damaged in the accident. The pipes are Jardines, BTW

[TopCatGr58]

Hey John,

I D/L'd the Jardine 2005 catalog, they list the Flared Chrome Slip ons for their systems, the # for the XS11 series is:
14-2202-01, but they don't show any 4-2 sets for the XS11, only the 4-1 megaphone style, so not sure why they list the slip ons, unless its for putting onto OEM pipes, as well as their older pipe sets that are out there still on bikes!?
T.C.

[TopCatGr58]

John,

I found a reference to that slipon at the following web site, but they only say they will be anybodies prices, but you have to call for their price!?
http://www.starcycle.com/street/jardine_yamaha.html

This photo is from Dennis Kirks site, not the exact same thing, but should represent what it should look like!


Hope this helps? T.C.

[rover]

I have a set of those Jardines 4-2 on my SF. The pipe diameter where the mufflers connect is much larger than the mufflers that are available. John, if you find mufflers that will fit these large pipes, let us know. My mufflers are rusted pretty badly.

[denysp]

So it turns out I have a 1980 SG not SF as I had mentioned before. The new jets are on order and while I wait for them to get here im going to pull the spark plugs and have a look at them, maybe even post a picture if I can figure out how.


How complicated is it to change the jets? like on a scale of 1 - 10. I do have a Clymers repair manual...

[DiverRay]

The hard part is getting the carbs off and back on the engine! the jet change is easy.
Drain the gas and then pull the carbs off the engine. Flip the complete assembly over, and pull the float bowls off. Lay everything out so it will go back on the same carbs! The jets are easy to see, and can be changed at this time. I would also check all the float levels, and make SURE they are the same across all the carbs.
Once done, just put it all back together and enjoy the ride, and the 35+ MPG you should now be getting!