28 mpg

[jetmechmarty]

My timing was set @ 2-2.5 degrees BTDC. It is now 5 degrees BTDC. The vacuum advance works now too. I had to turn the idle down. Seat of the pants says it pulls stronger.

[BA80]

That 80 has a much slower advance curve that the 78 - 79. Did you check your total advance now?

Advancing it may or may not affect your higher RPMs. Particularly a fully warmed engine in high gear at highway speeds. You might get some preignition.

[jetmechmarty]

Greg,

I drove it. I didn't get any detonation. If the mileage comes up I may call it good.

[ViperRon]

Not to take away from what others have said about miliage there are other things to consider that make a difference in miliage. First of all altitude can make a difference and it will also make a differnce in power. Tuning a bike for high altitude is much different from sea level and will make a difference in miliage. Climate such as a really cold wet climate versus a dry hot climate. Other things on the bike can give you cause to worry you are far off from others when you are not that different also. That odometer in these bikes like some speedometers is not to be trusted unless you check it. The only good cheap check I know is using mile markers on a long highway to identify how close it is to correct. I am sure some GPS systems can give an accurate reading also but everyone has mile markers not all have a GPS. Until you have really verified your odometer and the other guys odometer and you are running in a similiar geographic area how can you say your bike is not getting good miliage. One other issue with miliage is how lean and how hot you run your bike. Personally I worry about running an air cooled bike as lean as possible if you are out in 100 degree heat. Now if you are in a 70 degree climate in the rocky's it is a totally different situation. Another issue with running these bikes so lean is the methanol in gas these days which makes them run cleaner but also hotter.

Just my opinion but personally if my bike runs good for what I use it for then I have no intention of de-tuning or burning my valves trying to get 50 MPG

[jetmechmarty]

Thanks, Ron.

I'm not trying to get 50 mpg. Mine is just so lousy that I had to assume something wrong. I spent a day riding with two other guys on XS11s and I'm not even in the ballpark. I think correcting my ignition timing will put me into the normal range for a XS1100. If I start seeing 35 mpg, I'll be OK with that.

[James England]

Just my opinion but personally if my bike runs good for what I use it for then I have no intention of de-tuning or burning my valves trying to get 50 MPG

Exactly. If I want 50-75mpg, I'll ride my 100cc moped..

[TomB]

Just my opinion but personally if my bike runs good for what I use it for then I have no intention of de-tuning or burning my valves trying to get 50 MPG

Couldn't agree more, I generally "ride em like I stole em" and bollox to the fuel mileage, my bikes are tuned for power not economy.

As Marty says though, its kinda hi-lighted when riding with a bunch of fellow XSers when you all fill up at the same time, all filling the tanks over a weeks road trip and they're putting in lots more than you.





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