Treadmill powered pusher trailer for bike

[BenjaminT]

Originally Posted by Frank Lee

Is this known from experience or speculation?

Random day at work:


I don't know it all, but I've got some experience on the subject of alignments. There are other considerations as well, like higher than normal tongue weight or length to counter the torque lifting the rear of the bike.

Perhaps all these forces are negligible, however. You cannot deny their existence.

[Frank Lee]

Having had several one-wheel-drive go karts and such, and knowing King Midgets were also 1WD, my experience is that there may be a slightly noticeable effect upon "hard" (they had low power) acceleration; it was negligible and I'd do a 1WD vehicle again.

However, I've not ridden a bicycle powered by a trailer so that's why I asked. My intuition says the effect is probably noticeable yet manageable or even ignorable.

[BenjaminT]

Aha! I had it stuck in my head that this was to be some sort of two-wheeled load-carrying device that hitches up. If this is just a one-wheel affair, then all is well. Just get it tracking straight and you're good to go.

If it were a more traditional design, like those little child carts you see, then things get a little more interesting.

[Frank Lee]

I would imagine if it's to carry a heavy load of batteries a 2 wheel layout would be better? Or if it doesn't have many batteries 1 wheel should be OK.

1WD and having one wheel on one end are different things.

[lumberjack_jeff]

But I do mainly want it for carrying loads between workshops a couple of blocks apart. I think 2 wheels with one driven, hitched to the seatpost would be best if odd handling could be mitigated.

10 batteries? Ouch. Given the constraints of a bike, what is the most practical battery bank? UPS batteries?

I will do some 24v testing, maybe the inverter is a reasonable interim solution.

[Ryland]

I don't see a problem with a single wheel trailer, people really like the Bob trailers that have a single wheel, but if you want a larger trailer like the Bikes At Work trailers and if you want it for hauling stuff then I think that a two wheeled trailer is going to be easier to load stuff on to.
As far as drive wheels, I see a few options, a single wheel drive on a two wheel trailer and design the hitch to be as low as possible so the trailer doesn't knock you over then just live with the effects and handling that it will cause, or you can do a two wheel drive trailer either with a differential from an old ridding lawn mower or go cart, you can buy one new from Northern Tool for $100 and it will weigh around 10-12 pounds, or you can put a free wheel on each drive wheel so the wheel that is going faster freewheels when you go around a corner, this is going to give you some odd handling and is not going to allow regen braking but it would be simple, cheap and light weight.
Another option that might give you the best handling is to mount the electric motor on the bicycle, put the batteries and controller in the trailer with a quick connect plug so you can leave the trailer behind if you want to ride the bike, then you'll be left with only the weight of the motor on the bike.

As for options for your high voltage battery pack, if you don't need a lot of range you could also go with lithium batteries, I have 4 lithium battery packs on my electric bike, they are the 36v (really are 33v) and can be wired up to give you 132v and those 2.6amp hour packs would give you around 10 to 15 miles of range and take up as much space as 4 bricks.