Tips for improving MPG

General discussion about Street two-stroke Suzuki motorcycles.

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ro55o
On the street
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Country: yu
Suzuki 2-Strokes: t500, kz400,bsa b175

Re: Tips for improving MPG

Post by ro55o »

Thanks, for that. :up:
Cheers
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johnakay
I likes them jubblies
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Joined: Wed Oct 15, 2008 11:19 am
Country: UK
Suzuki 2-Strokes: bike

Re: Tips for improving MPG

Post by johnakay »

on my last bike 'M' model with a set of gt500 carbs I use to get 40/45 mpg,
in other words I would hit roughly 90 miles before the reserve kick in.
back in the day when I was younger I got 45 out of my 'J' model.
always 90 then it need a fill up.
not sure how much a T500 tank hold 2 uk gal?
If I wanted to make a life-long career out of
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argo1974
To the on ramp
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Re: Tips for improving MPG

Post by argo1974 »

Those air filters on the bike are junk and should be replaced with foam filters at least.
With late cylinders combined with early short intakes, both of the Suzuki's stock jetting variants (early or late VM32) won't work properly.
I think VM32-193, VM32-33 stock jetting would have been good starting point.

Since most of the riding occurs at part throttle, carb needle size+position and needle jet size+type affects fuel economy the most.
You may try dropping the needles a notch or half a notch (e.g. with special washers available on ebay).
40+ MPG at constant speed of 55 MPH should be easy on T500.

T500 stock jetting is very lean up to 1/8 throttle, about right in the middle and overly rich from 3/4 to full throttle - no matter, if early VM34, homo pressure VM32 or late regular VM32.
1x T500 Cobra (1968)
4x T500K (1973)
Vintageman
Expert racer
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Joined: Tue May 18, 2010 5:38 pm
Country: USA
Suzuki 2-Strokes: Suz, Yam, Honda, Kaw.
Location: New Hampshire

Re: Tips for improving MPG

Post by Vintageman »

I get low 40 miles per USA gallon on 1975 T500. That is street riding and not trying for best MPG....

The key to getting proper gas mileage street/road cruising in your needle jet and jet needle. The Jet Needle must be perfect inside where it meters. No way do a i believe 40+ year OK stock parts fit that criteria (at least in the region of the world I am in). The Jet needle must be pristine. Then even one clip position to rich is at least 5 mpg. Sometimes you won't notice anything different with making needle clip pos one richer - except for this loss of mpg. Oh you need to make sure your air filter is new and NOS. And. if you are a few degree too retard you loose a few mid range HP as well.

These tanks are small, 2 stroke are not the best using fuel efficiently (just ride behind one for a while) It is suck to get +/-30 mpg for where I ride gas station are few and far apart. And, it stick real bad for anyone behind you... I pull over if not too dangerous
Current Bikes
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76 GT250 (T350 upgrade),
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74 GT380,
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johnakay
I likes them jubblies
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Joined: Wed Oct 15, 2008 11:19 am
Country: UK
Suzuki 2-Strokes: bike

Re: Tips for improving MPG

Post by johnakay »

can you not get 1 tooth bigger at the front this surely would add a little more mpg?
I always do this to my modern bike.
I have a Tracer 700 and put a 17 tooth front sprocket on.
std is 16 tooth.
knock the revs down by about 400 and add roughly 6mpg with no effect on performance.
whether this will work on a two stroke? but worth a try.
If I wanted to make a life-long career out of
working with the mentally retarded I would
have opened a Harley Davidson Dealership
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