SOooo, my first question.

I'm looking to have some offroad fun in my Glitterbug so I've been looking at BF Goodrich and Insa turbo offroad/4x4/mud style tyres just for the rear, not familiar with 4x4's it took me a while to realise that the '32' in 32x10.5R15 means a rolling diameter of 32" which is considerably more than the 24"(ish) of a standard Bug tyre.

One of the reasons the previous owner took the Glitterbug off the road was the loss of second gear possibly due to over size tyres fitted previously so I'm currently looking for a gearbox.

So I'm wondering if there is a favoured rear tyre size for off road use?

And is the 4.375:1 FDR suitable or should I be looking for a Type 2 box with reduction hubs?

Thanks in advance for any help 

I've got a 1300 4.375 SA box up for grabs down in Dorset for £50 if you are interested?

It was only swapped due to me fitting a 4.125, no axles with it but it selects all gears fine and no noise.

Have PM'd you 

I should have probably also mentioned the rear rims I want to use are 15 x 8" wide and the engine is currently a 1200.

A really common size a lot of people prefer for the rear is 275/60/15, that equates to 28 x 10.8 x 15. Another size some people use is 255/60/15 which equals 27 x 10 x 15. and 235/70/15 equals 28 x 9.3 x 15. all will fit on an 8 inch rim, just depends on how wide you want and whether you want your rear arches to cover the tread.

Thank you, gives me sizes to look for...

https://tiresize.com/height-chart/

This may help with your selection

Paul