Utility Cycling - Has anyone ever built a Tandem axle trailer

Has anyone here ever built a tandem axle trailer. I don't see any real advantage to it except for the fact that you could have no weight on the bicycle. Would there be consiserably more rolling resistance than a 2 wheeled trailer with about the same amount of weight on it. Once I rigged a wagon with a plastic cargo area with pneumatic tires to my Varsity and filled the wagon to the top with sand. The tires needed a bit of air, so all four of them were semi flat. This was on a dirt road with gravel filling in potholes. I couldn't get the rig to start for two reasons, 1st, the Varsity's lowest gear ratio is 37 gear inches. Second, There was no weight on the bike and it had skinny tires on a loose surface, so it couldn't move the rig. I finally got it to move but I couldn't keep the rig going because I couldn't keep my grip and the rig came to a grinding hault. How do you think it would handle loaded and unloaded, at speed?

I own a trailer, the thought just came to me. So I had to ask

Did some thinking but did nothng about this. Also becouse I try to use my dog to pull stuff, and for him 4 wheels is better than 2 of course.

The main reason for not building is there is "garden carts" already on the market in all sizes and weight limitations, from childrens toys to the size you could pull behind a small tractor (gras cutter).

I think somebody in this forum posted about doing it.

Weight, tyre preassure width of tyres and type of bearrings are some of the things that would decide on rolling resistance, but for sure it would be heavyer. This is one of many reaons I use a longtail bike instead of a trailer most of the time. Also, with most of or all the weight on the bike you do not get the problems you describe

Not important really, since this is somethimg most peopel would not use as a only trailer. I am sure for some purposes it could be great, especially if you already own one.

Has anyone here ever built a tandem axle trailer. I don't see any real advantage to it except for the fact that you could have no weight on the bicycle.

The main reason for more than one axle on any trailer is to increase the load capacity of the
trailer. That said, one axle is all any sane person would ever want due to steering changes
as well as a load to heavy to carry,but mostly steering changes. Every watch a tandem turn?
Then you know the rear axle drags a lot and resisit turning at all. Don't want that on a bike!

Has anyone here ever built a tandem axle trailer. I don't see any real advantage to it except for the fact that you could have no weight on the bicycle. Would there be consiserably more rolling resistance than a 2 wheeled trailer with about the same amount of weight on it. Once I rigged a wagon with a plastic cargo area with pneumatic tires to my Varsity and filled the wagon to the top with sand. The tires needed a bit of air, so all four of them were semi flat. This was on a dirt road with gravel filling in potholes. I couldn't get the rig to start for two reasons, 1st, the Varsity's lowest gear ratio is 37 gear inches. Second, There was no weight on the bike and it had skinny tires on a loose surface, so it couldn't move the rig. I finally got it to move but I couldn't keep the rig going because I couldn't keep my grip and the rig came to a grinding hault. How do you think it would handle loaded and unloaded, at speed?

I own a trailer, the thought just came to me. So I had to ask

It could be done... if you had a need, but I can't think of circumstances that would need a tandem where a single wouldn't do the job. If you're talking about moving such a big load that you require at least 4 wheels then you'll probably need more than 1 person pedaling, and a pretty beefy prime mover. By that stage you could start to look at a side-by-side 2 seater quadracycle to get the job done. hmmmm, sounds like a fun project ;)

Has anyone here ever built a tandem axle trailer. I don't see any real advantage to it except for the fact that you could have no weight on the bicycle. Would there be considerably more rolling resistance than a 2 wheeled trailer with about the same amount of weight on it. Once I rigged a wagon with a plastic cargo area with pneumatic tires to my Varsity and filled the wagon to the top with sand. The tires needed a bit of air, so all four of them were semi flat. This was on a dirt road with gravel filling in potholes. I couldn't get the rig to start for two reasons, 1st, the Varsity's lowest gear ratio is 37 gear inches. Second, There was no weight on the bike and it had skinny tires on a loose surface, so it couldn't move the rig. I finally got it to move but I couldn't keep the rig going because I couldn't keep my grip and the rig came to a grinding halt. How do you think it would handle loaded and unloaded, at speed?

I own a trailer, the thought just came to me. So I had to ask

IF, you're really thinking about building one - there are a few things you need to know about how tandems act (this coming from a truck driver's experience):

First, if you are thinking about a true 'tandem' where one axle is only a few inches in front of the other, you will definitely increase the load capacity of the trailer. But, you will set yourself up for some serious difficulty in cornering. In order for the trailer to turn, the axles act against each other creating sideways friction on the ground (tire scuffing). The farther apart the axles are - the more friction (sideways) you will get as the actual pivot point is centered BETWEEN the two axles. You will also most likely have too much on there to get it moving. You'll need some SERIOUS granny gears

Second, using tandem axle does NOT remove the weight from the tractor/truck (or bike). It increases the amount of weight that you can carry. You do 'balance it out' but not in the way you may be thinking. We use sliding tandems to balance the weights to get the loads legal - moving weight on and off the tractor/trailer axles by shifting the balance point. On a truck you can go only 12k pounds on the steer axle, 34k pounds on the tandem drive and 34k pounds on the trailer tandems - for a max of 80k max weight (Fed laws, I ain't getting in to state laws :innocent: ). Without a trailer (or load) my tractor weighs in at 19.5k, An empty trailer is 8-20k depending entirely on the manufacture/type/materials/etc.

Second, if you really, really want to build one, look at tractor-trailers. The majority of the ones that you'll see have the tandems only a few inches apart. You'll see some out there that are called "spread axle" trailers. For the simple (and visible) reason that the axles are several feet apart. This is to spread the load more (and some can even slide those tandems up and back). But, and more important for you, it greatly increases the ground friction in any type of turn/curve. Their tires wear out much faster that the regular kind of tandems.

Third, if you really need an additional axle due to weight, I'd go with either a front axle that pivots (like a kids wagon) or create a "dually". Side-by-side tires. That will also increase the weight capacity (and increase the trailer width), but will not interfere as much with turning and ground friction - although there will still be ground friction.

And, finally, considering everything else - the alignment of the axles is critical! If you are off just the tinniest bit, your tires will be working against you. One will always be 'scuffing' the ground. You think it is bad when your car is out of alignment? Try it with a trailer out of alignment. You've probably seen them out there and not realized it. Where it looks like the trailer is following a different line than the tractor? It is - the trailer is out of alignment. And it doesn't take much. :eek:

What might be a better solution for you, at least where hauling more weight is concerned, is to get/build/buy a trailer with the axle in the center of the trailer. Then you can load it with the weight balanced between the trailer and bike. Or, (and if you do it I'd love to see a pic) create a trailer with a sliding axle so you can adjust it as needed.

Good luck

There isn't much weight on the bike with a trailer that is properly and safely loaded. Most of the weight should be distributed so the trailer axle carries most of the load with only 10% more of the weight on the hitch side of the axle for handling purposes.

The main reason for more than one axle on any trailer is to increase the load capacity of the
trailer. That said, one axle is all any sane person would ever want due to steering changes
as well as a load to heavy to carry,but mostly steering changes. Every watch a tandem turn?
Then you know the rear axle drags a lot and resisit turning at all. Don't want that on a bike!

True, my dad's boat is on a tandem axle trailer, but I was thinking more along the lines of a wagon.