What kind of bike wheels are these?

[Zirax]

http://img163.imageshack.us/img163/5195/bmxspecial007.jpg (http://img163.imageshack.us/i/bmxspecial007.jpg/)

I have seen this kit that uses 20" or 24" wheels. What kind of bike wheels are these so I can see if they do smaller wheels.

[Jonny69]

They look bigger than 20" but at the same time smaller than a 26" mountain bike wheel, so I'd say they are a 24? Probably a size off a kids mountain bike.

20" wheels are generally on shopper bikes and are about 16" overall diameter. God knows how they came up with the sizing convention on bikes, the diameters don't correspond to the wheel/tyre sizes even remotely.

On that trike the two hubs are different left and right. I would say that one wheel is driven and the other freewheels. If you get stuck you can always get the rims changed. Just count the number of spokes and buy a pair of wheels or rims in the size you want with the same number of spokes. It won't be the cheapest way to do it because you'll probably need new spokes as well, but it is possible.

[semi-pro waster]

It's quite difficult to tell from that angle as there's no real point of comparison to see what the hub height is in comparison to the front wheel. If you've got another picture then that might help.

The bike shows caliper brakes on the back which is quite unusual now so that suggests to me it's either an old bike (bit unlikely judging by the frame) or it's a kids bike as they tend to used older technology/be more cheaply made.

The adult all-terrain trike on Trikezilla.com has a lot smaller wheels but I've got no idea if it's what you'd want or whether they'd ship it to the UK.

[Zirax]

Thanks guys.

Good spot on only one wheel being driven! I thought they both were. I am more confused now though as by your workings Johnny a 16" wheel does not mean 16" diameter! How odd.

I had read the type of wheel was a hollow hub? Just thinking about what I would need to get in the way of a replacement hub if I wanted to go to smaller wheels.