A Level Design Project

[Swagrid]

For my A level design project i am going to be designing and manufacturing a trailer that can be towed behind a pit bike, like a moto mule or trail tail if any of you have seen those? I'll post a photo. I was just wondering if you guys would be able to give me any feedback/ information, ideas that you think that would be helpful, constructive criticism is also welcome. Also if any of you knew the towing capacity of a pit bike is? Or just a 125cc 4 stroke engine that would be great, i know they're not designed to tow things but it would be really helpful.
Thanks

[Dangle_kt]

Towing capacity aint easy to calculate, as its not pressing down on the bike suspension is it.

I had a mate who was 20 stone and he rode a 125 pit bike, the engine coped fine.

So I'd base it on your weight minus that to give you an idea of what it can take and maintain performance...

The weight it will place on the bike will be entirely dependant on how you place the wheels in relation to the weight holding area of the trailer.

[Swagrid]

ok, yeah that makes sense, cheers for the help

[Swagrid]

also does anyone know where i can find or know roughly how many pit bikes there in the uk/ world and things like how many are sold each year? i've googled it but cant find anything, i know its a bit of a longshot but worth a try. thanks

[Swagrid]

got my final design modeled up, any comments/ Questions?

[Jono916]

whats the payload limit? seems quite long has it strengthening beams

[duse118]

can't believe you aren't running usd forks on the front....

[Swagrid]

i've written in the design specifications that it should be able to carry max. 20kg. in one of the other picture i just uploaded you can see where it pivots horizontally, i think i might move the arms shown down to the bottom of the tube and having another bar at an angle to the top of the tube to reinforce it. ive also included the view from underneath, the main bar is a 50x50mm piece of box section so no worries about that not being strong enough, hopefully...

ooh i didnt think about that, not too good, hope the examiner does mark me down for not having usd forks

also didnt mention, all moving joints will have nylon bushings and the flat panel on the bed is aluminium treadplate, either 2 or 3mm

[Swagrid]

im also going to try reduce the space between the wheel and the trailer it seems pointless having such a large gap. the bike i imported and its a scale model of a honda cr50 with 10 inch wheels so its a bit small so the trailer looks a lot bigger than it should, the actual trailer will have a 12 inch wheel and the bed of the trailer measures 80cm by 40cm

[katoom]

Wouldn't it be better to have two wheels on the trailer and the front mount being able to rotate?


The weight of whatever your towing then won't upset the handling of the bike so much.