Modifications to increase fuel eficiency.

[Anonymous]

I have a 1980 GS1000 that I am rebuilding its engine.

Are there any mods. to the carbs, transmission gear ratios, timing, or ignition that can bet made that will increase fuel efficiency?

Thanks

gleblanc

bigteddy@breakthru.com

[Nerobro]

Yes... Make sure your carbs are running as lean as you dare. This is taking your engine's life in your hands mind you because you stand a chance of holeing pistons.

Drive in higher gears. never get over 2000 or 3000 rpm. Use big throttle opening's instead of reving the engine higher.

use a smaller rear sprocket. Same effect as the above....

Use a good exhaust. Stock counts ;-) High preformance exhausts don't hurt fuel economy, they just encourage more wild riding.

run higher tire pressures.

Get a bikini fairing. something that just bearly pushes the wind around you.

Um.... that's all I've got for now. :-)

[focus frenzy]

if it is a shafty "G" get a final drive gear box from a later model GK it will drop the cruse RPM a bit and give you a bit better milage.
go a bit slower, I get better mileage at 65 than 70. (2-4mpg better)

[Anonymous]

Are there any mods. to the carbs, transmission gear ratios, timing, or ignition that can bet made that will increase fuel efficiency?

Nerobro has it pretty much correct. You want to run tall gears to keep the revs down and big throttle openings, as the frictional and pumping losses are lower and the efficiencies higher. Taller gearing is a big help. Ride like a granny, minimal acceleration and no big handfuls of throttle anywhere. The only other thing you can really do is run a higher compression ratio, as that increases efficiency of the engine cycle.


Mark

[Anonymous]

I agree with the above advice except for one warning. Running in higher gears is fine at a steady speed. If you have to accelerate, however, downshift! Wider throttle openings will use more fuel than higher revs at a smaller throttle setting. It's all in the vacuum levels: open throttle means lower vacuum and lower gas mileage.

[Anonymous]

Thanks for the info. Question "Tall gearing" is that increasing gear ratio of engine sprocket to rear wheel sprocket?

[dpep]

Thanks for the info. Question "Tall gearing" is that increasing gear ratio of engine sprocket to rear wheel sprocket?

Increase your front sprocket size to create "taller" gearing which would give you higher mileage. Or you can reduce the size of the rear sprocket to give you the same effect. The fewer times the front sprocket has to turn to move the rear sprocket through a revolution, the better the mileage will be.

But do heed the warning about keeping the rpm's high enough not to "lug" the bike. Bad for the engine and can be dangerous in the wrong situation. More downshifting.