gas mileage comparison

freewheeling etc.

Perhaps I misunderstood what was meant by freewheeling. From a dead stop and with the engine idling (i.e., the clutch is not engaged) my bike will coast nicely down slight grades. The gears in the gearbox are being turned by the chain, but there's no connection to the engine. However, decelerating from cruising speed, the clutch doesn't disengage until I drop to about 5 mph. I could stop at the top of a hill, let the clutch disengage, and then coast down it, but I think I'd want to turn the engine off so as to not accidentally rev the engine and abruptly engage the clutch. My concern is that it would be easy to damage the clutch, gearbox, or perhaps even the engine. Is this an unnecessary concern?
 
With a 196cc 6.5HP engine............
Getting around 100MPG when cruising at moderate speed (25-30mph) with a good belt and just 1/3-1/2 throttle.

With a worn slipping belt and running full throttle and hard riding and playing around I still get over 60MPG.

I check my exact trip mileage with mapquest and calculate my MPG. I even got 91MPG one day but I rode a flat tire with the tube removed for over 8 miles to get to the store where I could replace the tube. Now I have a flat-free foam tube for my back tire.

Being the engine is larger and doesn't work as hard as a small engine I feel helps the MPG.
 
Perhaps I misunderstood what was meant by freewheeling. From a dead stop and with the engine idling (i.e., the clutch is not engaged) my bike will coast nicely down slight grades. The gears in the gearbox are being turned by the chain, but there's no connection to the engine. However, decelerating from cruising speed, the clutch doesn't disengage until I drop to about 5 mph. I could stop at the top of a hill, let the clutch disengage, and then coast down it, but I think I'd want to turn the engine off so as to not accidentally rev the engine and abruptly engage the clutch. My concern is that it would be easy to damage the clutch, gearbox, or perhaps even the engine. Is this an unnecessary concern?

Can't talk for the Hoot but the Grubee will coast just as well with the engager in and the throttle closed as it will with the engager out.
You can pull the engager in when you are going along at speed and the revs can match the speed but if you pull it in stationary with high revs you'll snap the key in the final sprocket shaft. You only do this once and then you learn not to do it again.
 
With a 196cc 6.5HP engine............
Getting around 100MPG when cruising at moderate speed (25-30mph) with a good belt and just 1/3-1/2 throttle.

With a worn slipping belt and running full throttle and hard riding and playing around I still get over 60MPG.

I check my exact trip mileage with mapquest and calculate my MPG. I even got 91MPG one day but I rode a flat tire with the tube removed for over 8 miles to get to the store where I could replace the tube. Now I have a flat-free foam tube for my back tire.

Being the engine is larger and doesn't work as hard as a small engine I feel helps the MPG.

Isn't this a 2-stroke motor? or is the Lifan a 4-stroke
 
I can't really talk about the free wheeling thing because I use the staton chain drive with a centrifugal clutch and a freewheel sprocket...so my gearbox never inteferes if I want to freewheel.

I get (if my odometer is correct) about 175 mpg using a 22 tooth on the gearbox and a 16 tooth on the wheel with staton's 18.75:1 gearbox. I upgraded to the 22 tooth for more speed and in the process I took a hit in my fuel economy as I was getting 190 mpg with the 19 tooth gearbox sprocket. It is important to note that my area is completely flat (coastal plain of virginia and nc).
 
Just finished first gallon of gas on a Honda GX50 and came to almost exactly 100 MPG. I have been told that other 4 stroke engines get between 185 and 200+ MPG and am really curious.
 
Just finished first gallon of gas on a Honda GX50 and came to almost exactly 100 MPG. I have been told that other 4 stroke engines get between 185 and 200+ MPG and am really curious.

MPG always improves over time, but I'd guess nearly 75% of the 4 strokes MBers are using are under 40cc, in that 1.6-1.8 horsepower range, which accounts for a lot of the difference.
 
Danny, I use the gxh50 2.5 horspower 49cc. If you look at my post from last year I posted about 175 mpg. I have since returned to a 19 tooth on my gear box. I've noticed a significant difference in fuel economy based on my average speed. If I venture too high out of the rpm sweet spot I can loose 25 mpg or more. I estimate the sweet spot to be somewhere around 4-5000 rpms by looking at the power and torque curves. Anything beyond this and the power still goes up but the torque goes down (the engine is starting to fight itself to go faster). I try to keep it at around 5500 rpm...its a nice compromise of fuel economy for speed (approx 27 MPH). BTW, my bike is really loaded. I welded my own rack using an old bed frame and I carry a bag on the front of my bike. With the battery the bag weighs at least 25-30 pounds. Even with this I get excellent mileage (admitedly I have no hills to climb). I have recently made some changes (added an idler sprocket and extra large gas tank from an old commercial lawnboy) which will likely have little to no effect on mileage, but I still like to watch it since this will likely be my first clue there is an engine problem. Of course, with gas prices going BACK up :cry: I will be doing all I can to maximize my mileage

Your fuel economy will depend on a lot of factors like engine rpm, hills, weight, sprocket ratios, prevailing winds, tire inflation, tire tread, general aerodynamics, type of oil used, quality of gas (no don't use hi octane...the extra octane is only useful for high compression engines), chain/friction/belt drive, gearbox or no, quality of all components, etc...if you're geared for power you'll lose fuel economy. If you're geared for speed you'll gain fuel economy (within limits of course). I'm curious, what's your speed at 5500 rpm's?
 
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Very cool. Thanks Bama and TV. More I learn about and ride the GX, the more I like it.
 
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I will never approach 175mpg. If I was cruising around at 20 mph or lower, maybe...or if I weighed less than 220 lbs....but I don't see either happening any time soon.
 
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