Low gas mileage!

Discussion in 'Motorized Bicycle General Discussion' started by AaronF, Nov 24, 2009.

  1. AaronF

    AaronF New Member

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    I am having problems with two of my bikes only getting around 30 miles per 1/2 gallon tank of gas,very odd if you ask me.I weigh approx.150,6'1 height 44T Sprockets on both 26" Bikes.I do run them at full throttle most of the time on the longer roads,it is mainly flat land here in my area.Everything is stock on both MB's besides the aftermarket air filter on one MB.I've checked the spark plugs on both,one of them is half brownish and the other one is just a bit oily/rich..What could be the problem here? Any help,I'd appreciate it!Thanks
     
  2. george_n_texas

    george_n_texas New Member

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    Could you have a fuel leak? Does seem mighty low mileage for sure.
     
  3. Charged-Reacter

    Charged-Reacter New Member

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    I have 2 bikes with 69cc engines and I am using 40T sprockets. One engine
    is straight sparkplug style with the old style carburetor. I run at full throttle on this
    one most of thev time. I get gas milage like yours.
    One bike is the slant head plug with the new style carburetor. This bike runs
    about equal in speed at half throotle and scares me at whole throotle because
    I am running with a rag style sprocket adapter. I am also seeing alot better mpg
    with this one.
    Do you think that it might have something to do with the carburetor slide?
    For some reason the new style carburetor has alot more throotle than the old style
    carburetor that I am experiencing.
     
  4. AaronF

    AaronF New Member

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    The carburetors seem fine,no sticking or anything.Sorry I forgot to mention..Both bikes are 2-Stroke 66cc one is a slant head and the other is a straight Raw.My buddy and I experienced this riding a 30 mile ride,country roads and some slight hills the other night but didn't expect to only get 30 miles out of a full topped off tank.Full throttling or not,it seems these should be getting much better than 30 or so miles..Thanks for your reply Charged!
     
  5. 2door

    2door Moderator
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    Aaron,
    You didn't say how long these engines have been running. As you've probably read here before they get better with time. Both power and economy will improve as the rings seat and the engines get some miles uder their belts. Obviously running WOT constantly will decrease your milage; just think how your car would respond to that. Back off on the throttle a little, give the engines some time to be fully broke in and see what effect that has.
    Tom
     
  6. AaronF

    AaronF New Member

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    They both have been ran 400+miles.I am mixing at 32:1 gas/oil with cheap synthetic oil.When I'm just riding around town my speed averages 10-25MPH witch most of the time I am cruising around town..On longer trips I ride at WOT for awhile and then let off giving it a nice cruising speed.
     
  7. captainrichhill

    captainrichhill New Member

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    run less oil=more gas per tank=better gas milage(to a point)
     
  8. Cabinfever1977

    Cabinfever1977 New Member

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    wow,i weigh 120lbs and ride at wot around 30mph and get 90miles per tank which is 180mpg and i running 32:1 with reg cheap oil and all stock except i have a air pipe with just a screen for a filter. 44t sprocket 48cc starfire engine reg head

    maybe your idle is turned up to high,try lowering it til it starts to stop and then turn in a little,enough just to keep it running and u will see better milage. also clean or replace your airfilter. clean your sparkplug too.
     
    #8 Cabinfever1977, Nov 24, 2009
    Last edited: Nov 24, 2009
  9. Maxvision

    Maxvision New Member

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    I met a guy who rides close to 70 miles a day. He's retired and dying of cancer so it's what he does to keep entertained. He's got the big tank and carrys 2 spare bottles of gas (about the size for a small Gator-aid bottle. He says he goes through all that gas every day. He says he gets about 70 mi. to a gallon of fuel.

    He's a big guy, well over 200 lbs with a regular 44t sprocket.

    Hope that gives you some insight.
     
  10. AaronF

    AaronF New Member

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  11. 2door

    2door Moderator
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    The valve, petcock, that comes with the peanut kit tank is a metric thread. The link you posted is for an SAE 1/8" pipe thread. They're not compatible. The kit valve is not a pipe (tapered) thread but a machine thread that relys on a gasket to seal. With that being said I will say that I ran a 1/8" pipe tap into the threads on a tank and successfully installed an 1/8" petcock. Maybe I got lucky so I wouldn't suggest you try it unless you want to take a chance. Dax and Sick Bike Parts carries replacement petcocks with the proper thread and gasket.
    Tom
     
  12. AaronF

    AaronF New Member

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    Eh I kinda figured it would be metric threading.I don't have $15 bucks to spare on a valve,so I'm looking for a cheaper alternative.Very informative 2Door Thank you!
     
  13. xlite

    xlite New Member

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    You didn't say which of the 3 common tanks sizes you got but that is in the ball park for new HT with middle size tank. With a big tank and leaned out carb you might get 40-45 miles. Then again you can also do what many do: lie. These are usually the same guys who claim 40-50mph speeds on stock engines.
     
  14. george_n_texas

    george_n_texas New Member

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    I'd just put an inline shutoff valve in there unless the one in the tank is leakin? To tell you the truth I don't know how many miles per gallon I get but it's a heck of a lot better than any car or motorcycle I ever owned and that's for sure!

    Happy Thanksgiving!
     
  15. Whizzerd

    Whizzerd New Member

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    Hi Aaron, ebay seller 'BoyGoFast' sells a fuel shut-off valve for $9.49 which includes shipping. Nice unit that comes w/ his kits. I'm using one. Works fine. Has "On", "Off" and"Reserve" settings. Handy since our tanks have no fuel gauge. His shipping is very fast, too. If your broken valve was on the bike w/ crummy mileage, might have cracked first and been leaking.
     
  16. bairdco

    bairdco a guy who makes cool bikes

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    last sunday i went 65 miles with a smashed, half gallon peanut, filled up 3/4ths so it wouldn't leak out of the cap, wide open at 35 to 40mph.

    almost ran out of gas and had to go to home depot for oil and fill up at shell. then i had to shake my bike around all crazy like i was mad at it or somethin...
     

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  17. DearthVader

    DearthVader New Member

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    I agree. I have a 66cc on a Schwinn Jaguar, hardly every open it up to full throttle and often help it a little up hills. My motor is fully broke in and I'm running about 28-30:1 fuel/oil ratio. I'd be lucky if I'm getting 80 mpg, probably closer to 70 mpg on a 41 tooth sprocket.

    There may be a few changes here and there which you could make (idle adjustment) but they're not going to give you a 100% increase in mileage which would get you in the ballpark that a lot of people are claiming.

    Frankly I don't see it happening and would be quite amused if someone could show me a bike with a similar setup that can approach 150 mpg.

    Josh
     

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