I got an extra front wheel form my first Berg.
The problem is that it was a 2001 and my present Berg is a 2004. Is it possible to get a mod kit to fit the 01´thinner wheel axle?
check the OD of both bearings and put the OD you want and ID to a bearing supplier. get a centre dowel made by an engineer or if you can - order it from the factory. the rest should be the same.
To answer your question direct--yes there is a kit. You can find it in the KTM Hard Parts catalog. It is a simple spacer arrangement. You must have the old 20mm axle to use with this kit.