SMALL 26.2cc 4-cycle engine - will it power a bike?

Discussion in '4-Stroke Engines' started by ZnsaneRyder, Aug 27, 2008.

  1. ZnsaneRyder

    ZnsaneRyder Member

    I found a cheap deal on some really small 4-cycle engines, and I'm wondering if they will have enough power for a bicycle. They go to 26cc 4-cycle MTD weedwhackers that are on clearance.

    The engine and clutch was easy to remove to use for a project.

    I'm hoping so, because only 26cc should get great gas mileage, and you never need to mix gas and oil.. I want to stay with 4 cycle for ease of use. My bike trailer with a 4 cycle 196cc engine gets 100MPG, I'm hoping a smaller engine on the bike can get much more.

    They already come with a clutch that you can weld on your sprocket or roller of choice.

    My friend bought one for his gas skateboard I'm rebuilding. The little engine will drive a jackshaft that drives the right wheel. I know it will have enough power for the skateboard, I just hope it has the power to also use on a bike.

    Is 26cc with a 4-stroke strong enough to make a motorized bike?

  2. astring

    astring Member

  3. JemmaUK

    JemmaUK Guest

    It will do it - but you will be assisting on hills although you'll get a fairly good top speed on the flat. MOST important is the right gearing, the smaller the engine the more you have to stay within its power band. Id recommend either a belt or chain direct drive of some description as that means less driveline losses

    Jemma xx
  4. ZnsaneRyder

    ZnsaneRyder Member


    That's good news. If I can put one on the bike, I'll try to aim for 30MPH or so. I'm so glad that mini 4-strokes have hit the market now and no gas mixing needed on small engines.

  5. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    How much are you paying for it?

    Who makes the motor?

    They will work but probably be a little slow

    You should get 175 + MPG

    Staton sells a friction drive with a Honda gx 25 and
    of course the Honda gx35 cc

    I just bought a Honda gx 31cc engine for $50 and its going on a friction drive
    Last edited: Aug 27, 2008
  6. JemmaUK

    JemmaUK Guest

    I have to say that I will always prefer 2-strokes for machines like this. My grandfather used to say 'the right tool for the right job' and in this situation with sub-50cc motors I think the 2-stroke is perfect. Mixing petrol/oil (and in my case a soupcon of Nitro) is little hardship when you consider that a 2 stroke can provide twice the power compared to an equal sized 4-stroke.

    My bike will top out at 35mph from 32ccs. Augi's machine will make 38mph. I dont think there is any 32cc 4-stroke will provide those figures even if it was insanely tuned.

    For volumetric efficiency and simplicity, in my personal opinion, the 2-stroke wins hands down.

    Good luck with getting your machine built and we want to see pictures when its done :)

    Jemma xx
  7. arceeguy

    arceeguy Active Member

    There are a lot of people that think the same way.

    IMO, 4 stroke trimmers and hand held blowers are inferior to their two stroke counterparts. They are heavier, less powerful, more complex than they have to be, and more expensive. This is why two stroke engines dominate in this area. (until they are outlawed by the misguided eco-weenies)
  8. astring

    astring Member

    the 4 strokes are cleaner and use less fuel, but have less power. The eho35 performs wonderfully. I top out at 28.
  9. cookcamp

    cookcamp New Member

    I'm getting close to 30mph out of my belt drive 31cc 4stroke clone, with a slightly higher octane fuel mix, and I'm a large rider. Cheers Martin.
  10. az cra-z

    az cra-z Guest

    Not legally, astring! Let's not be reading about your "in-car-ceration" in the Legal Issues forum.

    The small 4-stroke would probably be best with friction drive.
  11. Remember. You can't just chain it up to a sprocket unless you know what internal gearing you have on your engine. Is the output shaft directly off the engine directly connected to the clutch? Or from the clutch does it go into some gears before it exits to the drive sprocket?
    If your drive end whether it's a pulley for a belt or a sprocket for a chain is spinning just as fast as your engine the only choice you have left to get this all to work is a friction drive. You would need about a 5 to 1 reduction to fit a 44 tooth or so drive chain sprocket out back or at least a 3 to 1 I would guess not really sure for a belt drive. If you have 1 to 1,friction is the only way or have the belt pulley be as large as your wheel.
  12. astring

    astring Member

    in a parking lot:p
  13. Mountainman

    Mountainman Active Member

    30 mph may be wishful thinking - but - depending on your overall weight - body, bike and engine - you may come pretty close.. Which type of drive unit have you chosen - friction - belt - chain. If friction - will need at least 1 1/4" drive - I am thinking - to get to 30 mph. What ever you decide - remember to - Ride That Thing - Mountainman
  14. ZnsaneRyder

    ZnsaneRyder Member

    It's a weedwacker and the engine spins (according to owners manual) at 6800-9300RPM so I plan on using a friction drive if I use one of these engines. I don't know who makes the engine, so I assume MTD since they make the whole weedwacker.

    They are going for ~$100 at Tractor Supply

    It's so lightweight, and easy to hold in my hands while revving it up, and it sounds like small motorcycle instead of the typical weedwacker.

    This engine I have now belongs to my friend with the gas skateboard, but I am curious about getting one for myself for my bike.

    I want to have an engine to use when I leave my pusher-trailer at home, and I'm interested in having them BOTH for the bike, so if my trailer breaks, I still have a backup engine so I won't have to pedal myself to exhaustion from towing that heavy beast!

    Another option would be to use the little engine by itself on days I don't need the power and speed of the pusher trailer, then just use the trailer when I need to go faster than 25, or haul stuff.
  15. mark2yahu

    mark2yahu Member

    My bike is powered by a 25cc Robin-Subaru engine on a GEBE rack mount. I get a decent 25mph on it.
  16. ZnsaneRyder

    ZnsaneRyder Member

    I hope so. I'm actually more interested in a Honda GX50 now. Any recommendations for a cheap Honda or clone?

    The 26 cc isn't as strong as I'd hoped, so it would need REALLY low gears. I can rev it full throttle and hold the clutch from spinning at all with my hand until it gets too hot to hold. That's not much torque. I'll just stick to using it on the powered skateboard.

    Pic of skateboard and engine.
  17. rkbonds

    rkbonds Member

    I'm using a 24 cc weedeater engine on my bike with friction drive mounted on the rack. I like the setup I have my only problem is I need to do a little more work on the drive wheel. I'm going to be trying the jb weld and sand trick and hope that gives me the added friction I'm looking for. I weigh 200 # and my bike weighs 60 + with all my mods and I'm running 20 mph easy.
  18. kerf

    kerf Guest

    One question / observation. As the quality of clones are regularly questioned in this forum and the cost difference would be only $100 - $125 between the GXH50 & its clone, what is the fiscally responsible option?
  19. ZnsaneRyder

    ZnsaneRyder Member

    For me, it's the clone, because $100 difference is a lot of money, almost enough to get another engine. My 196cc engine was only $130 so it kills me to spend a lot of $$$ on a puny 50cc engine, when the big engine is way cheaper and has much more power.
  20. dchevygod

    dchevygod Member

    deamon 31cc friction drive

    I just ordered This kit that claims up to 40mph out of a little 4 stroke