Hi from  John the founder of Go Kart Daddy
Building go-karts has always been fun times for me I used anything I could find as a lad growing up in Weymouth Dorset. 

Wheels were the biggest challenge and when you finally found  some there was the next problem what to use for axles. 

The old silver cross wheels were the best and very hard to find any that  are not worn out these days. In 2005 I made a one page website offering free plans on how to  build a wooden go-kart based on my hobby interests.

I quickly had great response to this webpage mainly about sourcing wheels and axles. I now can supply & make go-kart axles, hand-brakes and all parts for fun family days out.
Showing that in this high tech world of ours, low-tech traditional products are still the best. More details at My Story