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I'm trying to design a 5 foot by 10 foot trailer to tow behind my bike and wanted to use bike tires.

I googled this: "bike tire load chart" — but found nothing useful there.

The most useful thing I found was a site for "big people" and they had bikes that supported up to 550lbs on 2 wheels.

I am looking for more like 1000lbs on 2 wheels.

Actually I found some charts here and it looks like that about 500 lbs is max.

It looks like a motorcycle tire might be a better bet. See here

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    Towing a 1000 lb load behind a bicycle does not seem to be a sensible thing to do. It would be very hard to get the trailer moving, almost impossible to steer and extremely hazardous trying to stop. On even the slightest downhill slope you would not be able to slow down at all. Note that manufacturer's suggested maximum towing weight is often less than 1000 lbs for a small car. – Penguino Sep 12 '18 at 21:52
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    I don't think any bicycle brake on the market would be sufficiently strong to stop that type of weight. – Rider_X Sep 12 '18 at 23:37
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    A one axle trailer will either put a lot of weight on the attachment point and overload the rear wheel of the bicycle. Or it will do the exact opposite and lift the rear of the bicycle in a way that the rear tyre will not be able to apply enough traction. – Carel Sep 13 '18 at 9:04
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    See Moz's answer at bicycles.stackexchange.com/q/1256/7309 and the links in it (e.g. a 4-person band on a trailer pulled by a recumbent trike) – Chris H Sep 14 '18 at 6:07
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    @Carel When you said "and lift the rear of the bicycle in a way that the rear tyre will not be able to apply enough traction" I an only picture the trailer tipped back at an angle of about 40 degrees, with the rear tyre of the bike hanging about head-height above the ground... in which case it would definitely be difficult to get any traction. – Penguino Sep 19 '18 at 21:39
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At those weights you're looking at three wheels minimum and maybe four.

Simply loading 1000 pounds (500 kg) onto a trailer will be difficult without a lifter of some sort, and you would have to balance it perfectly over the axle. On a car trailer, nose weight can be several hundred kilos acceptably, but on your bike any more than 2-5 kilos could see the whole thing rotate on the axle while loading.

Three wheels with a super-low slung platform would be safer.

You'll also require power brakes because 500 kilos is a LOT of weight. I've ridden with 100 kilos on a trailer and it was really too much - had problems getting moving, and it was hard to get over intersections from stopped.

A 2 degree upslope in the road to go over a railway crossing damn-near stopped me cold, and the similar downslope on the other side was a surprise too.

Also check with your local road rules about what constitutes a maximum size and weight for a bicycle. Could be the dimensions you're planning make the bike too big and could be classed as something else.

Don't be a danger to yourself and other road users - this project sounds dangerous. I'm all for bikes in life, but look to hire movers or use a car trailer for this one.


bikecalculator.com says that a 500 kilo bike with a 75 kilo rider doing 150 watts on the flat will achieve around 15 km/h (9 mph) Same combo with a bike of 10 kilos is 28 km/h

I haven't got a good calculation for stopping time for those masses from those velocities, but 5 times the weight will take a minimum of 5 times as long and your stopping distance will be much greater, to the point it would be unsafe for you and others to be sharing the roadway.

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    For a bicycle trailer in the EU the 'voluntary' i.e. recommended limit is 60kg (if it is inserted in national laws). prlog.org/… – Carel Sep 13 '18 at 9:31
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    Braking distance will only increase (and drastically so) if the trailer has no brakes. If you somehow manage to add hydraulic brakes to the trailer it should stay roughly the same. – Michael Sep 14 '18 at 10:41
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I think you need to use 4 wheels for the trailer not because of wheel ratings but because for this kind of weight on a rectangular lightweight platform, even relatively small irregularities in weight distribution would topple even a 3 wheel trailer.

Then we are at 125kg per wheel. I'm sure you can find wheels that handle that much.

Then the trailer would definitely need its own brakes and some system to trigger them either automatically (by mechanically redirecting the force with which the trailer presses forward on the coupling onto the brake levers) or through extra levers (which are either permanently mounted on the bicycle with a coupling in the brake cable, or with a removable lever and cable permanently fixed to the trailer). I assume systems to hook up multiple brakes to a single lever exist (for example: trikes with brakes on all wheels).

The brakes would only need to take about twice their usual load that way (500kg/6), I assume if you put the largest disc brakes you can find on relatively small wheels (say 20", disc brakes have mechanical advantages on small wheels), then the brakes should be easily strong enough so that tire to street adhesion becomes the weak point instead.

Selecting wide tires will ensure you don't need more distance to brake than some 80kg racer with 25mm tires.

This is no small project and even just the material cost for the prototypes (yes, I assume plural) and tools (I assume you don't have everything required) will easily exceed the cost of paying someone to move something of the mentioned weight and size multiple separate times.

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    Once you're up to 4 wheels the load per wheel is only a little higher than a heavily loaded tandem, so brakes and tyres should be easy especially as this won't be going far or fast (your 80 kg racer isn't a good model, think instead of a large commuter who's riding because they desperately need to loose weight). Actuating the brakes might be a problem though - it needs to be reliable. I'd consider 2 systems, with one being automatic (dynamo powering a servo when output goes over a threshold?) – Chris H Sep 14 '18 at 6:01
  • The dynamic shift of the load when 'accelerating' will tend to remove so much weight from the rear wheel of the bicycle that the tyre will simply skid. The other way round, braking will overload the rear of the bike. – Carel Sep 14 '18 at 9:59
  • @ChrisH I think systems that automatically brake a trailer in a purely mechanical, foolproof way may already exist. They are absolutely feasible for sure. – Nobody Sep 14 '18 at 12:57
  • @Carel While accelerating, a properly designed coupling won't generate any lifting force on the rear wheel. It's even possible to design it so that acceleration generates a downward force. And when braking: The automatic or manual system needs to brake the trailer the roughly same amount as the bicycle. – Nobody Sep 14 '18 at 13:03
  • @Nobody, yes, there are overrun brake designs as well. My electronics abilities are better than my mechanical abilities (especially when it comes to robust moving parts) so I'd tend towards that approach – Chris H Sep 14 '18 at 13:07

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