tagalong and trailer pushers

Discussion in 'Push Trailers' started by paintvalleymusic, May 25, 2007.

  1. If anyone has motorized a tagalong or trailer and used it as a supplemental pusher.....please contact me. I want to motorize my bike, but don't want it to be a permanent attachment. Seems like motorizing a tagalong or trailer would be the way to go.....then just unhook when you don't need the assistance. Just another crazy idea floating around in this head of mine. Thanks

    I know this has already been done, but want to talk to someone who has actually used one or talked to someone who has. Thanks

  2. power trailer, pusher trailer, motor trailer

    I just joined this forum & found this thread soon thereafter. I built one and am gathering parts for a more sophisticated version. I made the first one about 20 yrs. ago. I've renewed my interest recently. You can see my first one in Google videos here;


    Another (FWD) powered bike I made is here;


    Several people seeing the video have contacted me for further info and I answered all of their questions. The trailer is the easiest way to power a bike I could devise. No welding was necessary, no modification of the bike was necessary and no extra stresses are placed on the bike. I have several ideas for different versions, accessories etc. I built it in 2 evenings entirely from scrounged and garage sale items for a total of $40.
    It handles extremely well. It doesn't affect the handling of the bike in the least except when making the tightest low speed u-turns. Even those are easily manageable after you've done it a couple times.

    The one I'm making next uses a 7 lb. Honda GX31, 4-stroke, 1.5 hp engine w/a double-bearing centrifugal clutch. The wheel is a 16 inch bike wheel laced onto a 3 speed hub. Primary reduction will be by cogbelt and final drive will be chain. 3 spd. hubs freewheel so the trailer will be easy to tow when the engine is not running. The one in the video does not tow easily due to the drag of turning the chain and clutch. 3 spd. hub ratios are 75%, 100% (direct drive), and 133%. I plan to gear it for 15, 20 and 27 mph to start with; perhaps changing it for higher speeds after I break in the engine. I'm retired and plan to use this vehicle for long tours, so I have to start thinlking about cargo capacity.
    I may also experiment with a CVT I have for this engine, but I expect the 3 speed hub will be more efficient.
    I hope to make a very quiet muffler from a propane bottle or fire extinguisher canister. If it's disguised and very quiet, I can go anywhere with no more than a glance from the constabulary. Who would suspect a trailer is actually pushing the bike?
    You might have noticed I have another Google video showing my sailbike.


    I plan to upgrade that to a larger more efficient wingsail.
    Ideally, I'd like to be able to use wind and pedal power as much as possible, reserving the engine for long or steep uphills, strong headwinds, laziness, full belly, old age etc.
    Closing now to scour this forum for more ideas.
  3. OldPete

    OldPete Guest

    The smile on the youngster's face in the FWD vid says it all. :D

    Three speed hubs are not considered strong when subjected to non-human horse power. Please let us know how it works out.
  4. az cra-z

    az cra-z Guest

  5. Thanks for all the 'welcome messages' !
    I guessed that engine power (1.5 hp) might overstress a 3 speed hub, but I figured placing the hub in a small wheel would reduce torque through it by exchanging torque for RPMs. A strong adult can briefly produce 3/4 hp I've heard. Surely the hub must be overbuilt to some extent for durability. If we consider axle to ground distance as a lever for the torque from hub to ground, half of a 26 in. wheel is 13" and half of a 16" wheel is 8'. 8/13 =.614 so torque through a hub is reduced to 61% when taken from a 26' to 16" wheel. I need to examine the innards of a 3 speed hub first, but I suspect that using 2nd gear (which is direct drive) most of the time would make it easier on the internals. Doing it that way would reserve 3rd gear for an infrequently used overdrive. If the engine still tore up the hub, I could re-lace it into a 12.5 in. wheel which would cut the torque to 48%, or I could use a multispeed hub in the jackshaft where I'm sure it could cope.
    Scrappyscooter.com uses a 5 speed hub as a jackshaft with a 43 cc 2-stroke. If it doesn't work he has a lot of nerve asking $20 for VHS plans and $29 for DVD. It seems like a good idea to me. Seems like 3 speed hubs would be sturdier than 5 speeds. They're cheap & easy to find in almost new shape. Unfortunately I won't have a workshop until Spring.
  6. TheBadBunny

    TheBadBunny Guest

    The Third Wheel Bike Pusher

    The idea of a motorized trailer has appealed to me ever since I saw the old Go-Devil plans on eBay. (I wouldn't advise buying them, they're a good five decades or more out of date). I finally found a commercially produced one on the Internet called the Third Wheel"


    A complete Third Wheel kit sans engine runs $288.00, and a complete Third Wheel with an engine already installed goes for $498.00, and for the do-it-yourselfer, you can buy just the trailer for $148.00 and rig your own drivetrain and motor. Pretty nifty! It would, I imagine, be fairly easy to hide the engine on this thing!

    I'll try to post a photo now.

    Attached Files:

  7. srdavo

    srdavo Active Member

  8. TheBadBunny

    TheBadBunny Guest

    There are several electric trailers to push your bike along, like the TKO motorized trailer (http://tkotrailers.com/), which is relatively affordable at $398.00, the PT50 (http://www.geocities.com/vancyclist/PT50.html), which looks like a tiny teardrop trailer and isn't very affordable at $1200.00 but boasts speeds up to 55 kilometers (34 miles) per hour, and, of course, the Bidwell Bike Pusher, plans available from http://www.rqriley.com/. The problem, of course, is that they have all the drawbacks of electric bicycles (heavy weight, limited range, and, unless you're willing to pay thousands for, say, a Phoenix Racer, very limited speed). On the bright side, however, they're completely street legal. :grin: But the Third Wheel is the only commercially produced gas-powered pusher I've come across.

    And come to think of it, the first two web sites listed above looked awfully old. They might have gone out of production like the Motobob!

  9. srdavo

    srdavo Active Member

    Last edited: Jan 6, 2008
  10. BSA

    BSA Guest

    Dennis, you are a genius. The bike in the video is mad. Do you have a front brake? I'm guessing the transmission is friction drive straight to the tire.

  11. It's made with a rear minibike wheel that has a good expanding shoe brake in it that stops it very well. It uses a centrifugal clutch with a chain directly to a sprocket on the wheel.
  12. mopedjay

    mopedjay Guest

    i thought about doing that but i dont think it would be legal in mass

    a bicycle can have a trailer but a trailer for motorized bike has to be registered

    but now we have a regular bike but with a motorized trailer so i dont know

    id like to build an electric trailer for my solex for that extra oomph to get up the hills
  13. smapadatha

    smapadatha Guest

    Dennis - how would you evaluate the hill climbing ability of a powered trailer like the 3rd wheel? On one hand, it seems like it couldn't possibly transmit power as efficiently as a GEBE kit, but, on the other hand, you could have a larger engine with a larger clutch.

  14. powered trailer hill climbing

    I live in the flatlands of Illinois & can gear for speed. The trailer never slipped even in gravel, partially due to tall gearing, but also due to using the seatpost hitch position. Precisely when you need it, you get extra traction when accelerating or climbing since the wheel is "tucking under" to some extent. In other words it increases its traction by pushing upward toward the seatpost. It is probably a small effect given the shallow angle involved, but I never had a traction problem.
    Stuart Brandt has a Comet CVT on his 3+ hp powered trailer and has a low overall ratio. He climbs steep hills, accelerates quickly and still has no traction problems except perhaps in gravel with excess throttle. You can see YouTube videos of his working well on grass. His hitches to the seatpost like mine.
    Interestingly, the trailer works best with just enough air pressure to keep the sidewalls seated. It appears fully inflated but absorbs bumps better and probably gets a little better traction as well. I used the trailer a lot and never saw any hint of tread wear. The curves in the tongue filtered out vibration. No vibrations were transmitted to the bike, which was quite a contrast from the FWD I built first.
    I strongly advocate powered trailers as a simple, easily built, versatile means of motorizing a bike. The only problem with a minibike wheel version is the lack of a freewheel which makes it difficult to tow when the engine is not running. That appears to be a weakness of the Third Wheel powered trailer as well. Since there's so little weight on the wheel, a 12.5" or 16" rear bike wheel will work just fine, solving that little problem. Make one with a derailleur or geared hub & you have everything you could want except bump start.
    I don't recommend a CVT unless automatic ratio reduction for hill climbing is a higher priority than partial throttle cruising and fuel economy.
    If you build a single wheel version, keep it rather long and low so pendulum effect will help keep it vertical. Imagine a line from the hitch to the tire's ground contact patch and keep more weight below that line. Make sure the wheel is aligned with the hitch or it will "dog walk" and tend to rhythmically sway laterally under power.
    I wouldn't want to build a 2 wheeled version, fearing it would have to be too wide to remain upright in fast or tight turns. I wouldn't want one wheel on the road and the other on the shoulder when trying to keep to the right as far as possible.
    Last edited by a moderator: Jan 6, 2008
  15. Any other powered trailers on the web? for sale, plans, photos?

    That Third wheel is new to me. It looks like a typical minibike frame with a tongue to replace the front fork. Something similar could be done with a pocketbike, a GoPed, or just about any little scooter. Too bad most of those don't freewheel for easy towing by pedal power. Thanks to TheBadBunny for the 3rd wheel link. Thanks to Srdavo for his trailer list. I had seen all the others listed here exceept 3rd Wheel. I wonder how many other powered trailers exist for sale , as plans, or at least as good photos. Does anybody know of others not already listed in this thread? Personally, I'm most interested in gas versions. I emailed the 3rd wheel folks asking why their mention of an electric version is not accompanied by a photo or mention in the price list. I'll post their reply.
  16. mslipac

    mslipac Guest

    after gettim my new used 18 speed bike home did some measurments and the engine that I was planing on using looks like it wont fit in the frame...PLAN B...trailer pusher :) looks very simple to make and reliable system...I am tracking down a good used frame from a minibike I can modify or maybe just get one from the dragonfly website the 3rd wheel setup
  17. TheBadBunny

    TheBadBunny Guest

    Here's a link to a homebuilt one-wheel power-assist trailer.


    He used an electric motor on his, but it seems as if it would be rather simple to put a gas engine on it.

    Or have you considered trying to motorize a cheap child's tagalong that clamps to the seatpost? Wal-Mart and Target sell 'em cheap.

    Let us know if/when you get a reply about the Third Wheel.

    And hey, why don't YOU draw up a set of plans when you're done? :grin:

  18. powered trailers

    Thanks Badbunny, but I've seen that one. For a long time I keep getting faked out by that one when doing searches for new ones.
    It's easier to make a trailer than to add an engine to a tagalong. Staton's looks top heavy to me. It's be good if you carried a little passenger often.
    I certainly will draw up a set of plans. I'm getting queries often about it lately from Youtube exposure. Just today I got a comment below the video from a guy who says he plans to make one with a Honda GX50. I need to make a set of plans for the FWD too.
    I've been referring them all to Motoredbikes.com.
  19. ibdennyak

    ibdennyak Guest


    Curious as to what conditions you are looking at. I've been running a 500 watt hub wheel on a pusher for about 8 months. Not overly fast, but very dependable. I've been riding in snow for the first time this winter. It doesn't seem to be any more of a problem than it normally would. Wiped out twice so far, but it was so slippery that walking was difficult. Total weight in the trailer is as low as about 40# (including the trailer) It will spin out before it slides the bike with brakes on, but I don't normally ride with the brakes applied anyway. :grin: Two of the hills I climb are about 10 degrees, and traction isn't a problem. Of course this is on paved lanes. I haven't tried it off road much other than gravel parking lots etc. so I don't know how it would do there.

  20. srdavo

    srdavo Active Member

    I REALLY like these pushers!

    I looked at the moto-bob, back in the days when I only pedaled bicycles. (I never could justify the pricetag) So, I opted for store-bought bike trailers. I've nearly worn out my 2nd trailer. ( my 1st one was stolen, after I put a solid body on it.)
    After I became a "motored" cyclist, I saw staton's tagalong, (Very impressive, as are all of staton's products.), but I wanted cargo capacity too.

    Now, you fellows are sharing your impressive designs.
    For that, I thank you.

    No alterations to the bicycle! Man...this rocks.

    Everyone knows I am somewhat of a tinkerer. :rolleyes::lol: I'd really like to build one of these. The best I can do right now is move this project toward the top of my "unfinished project" list. (everyone also knows I am the procrastinator :lol:)

    thanks again, for this inspiration....
    I may have questions later....:D