1982 GS1100GL Aero mods

[FXSTi]

Originally Posted by jkv357

Not to rain on the parade here, but...

If you wanted to go to that extent (making transmission gears), and were really looking for high mileage numbers, you would be better starting with a much smaller engine.

Modifying an 1100cc engine to any extent to increase mileage potential isn't practical or efficient.

If mileage numbers are the goal, sell the GS and get a 250 Ninja or CBR - then mod from there.


Jay

This is really more about getting the best mileage out of whatever you drive. Certainly a 250cc bike will get better mileage, but the 1100 is what he has.

[jkv357]

Originally Posted by FXSTi

This is really more about getting the best mileage out of whatever you drive. Certainly a 250cc bike will get better mileage, but the 1100 is what he has.

I was commenting on the idea of altering the transmission to give you a more efficient cruise RPM. That is way above and beyond just adding some plastic to reduce drag, and would be completely impractical for the amount of return you would get in this situation.

It's like trying to make a Suburban get similar mileage to an econobox. You are starting at a significant disadvantage. If you don't need a Suburban you are way ahead by starting with a different platform before beginning any significant mods.

Since we are talking about mileage, having 4 times the displacement to start with is a huge disadvantage and is not easily overcome no matter what length you go to.


Jay

[RiderofBikes]

so... here in the midwest, ive been able to find lots-o-parts for cheap. i know switching the stock crappy CV Carbs to flatsides, or other would improve power but would they have much affect on fuel consumption, given the engine still has to have an equal air/fuel mixture to match cc of the engine?

These Roller Bearing shaft engines are great for the Strip use if built up properly, looking to get lucky... looking to sell or trade for something along the 250-600cc range. Ride 2-up 50% of the time, so would be nice not to strain the next bike.

I only bought this bike for 500 in the beginning, so ive already saved loads!

[hzoltaan]

I have to agree with this.
I have a motorbike, an ancient 2 smoker. There is no point in eco(what's that??) modding.
on the other hand, I have this car, Suzuki Swift, 1.0 on lpg. Now that is something to play with.

I want to put a diesel engine into the Jawa frame though, but I have problem with the transmission.

the GS1100 frame would be able to accommodate a diesel block would it not? just get a bmw or ural gearbox, put it together with your shaft drive... but well, I understand if you're in love with 1.1 inline four.

[Christ]

hzoltaan - Use a CVT pulley system and a jackshaft like snowmobiles in older times. Many have done it. DieselBike.net The Original Diesel Motorcycle website.

[RiderofBikes]

I've recently been looking for a 2-3cylinder diesel to drop in for this large of bike, but no luck even at junk yards or pick-n-pull lots... I know trackers/bobcats have around 15-25hp would be more than enough for my commuting. But the ones i have found are a bit ($)$$$... its a good platform to do a swap in, but with the amount of work needed to use the existing shaft drive id need to do some major mods. Dependant it be a horizantal shaft, all ive found mostly are verical.
The swinger if needed can be easily swapped with a GS1100 chain drive unit if nothing else.

I by NO means plan on making this thing reach an unpractical goal of 65+ mpg as it sits now... But maybe doing what i can to an extent reaching 50-55mpg would put me right around $3.75 a day for my 60mile commute. I'm already at a consistant (46mpg).

The best part about the GS line of engine, is that most parts can be swapped. I could swap out the Topend with a GS1000 to reduce displacement. Or do smaller custom exaust and smaller jet kit as it is now. which wouldnt damper my wallet too much

[Grant-53]

Look for an engine broker of Ag equipment such as Kubota. A 3 cyl. 700 to 900cc will fit the bill.
A good fairing system will nearly double efficiency.