I'm converting one of my 400exc's into a 520 and the 520 cams are back- ordered for about 6 weeks
A friend of mine created this web site in one night and he used pictures of my garage, trailer and my bikes.
Check this web site out but you'll have to type it out.
Ph. Well there is a 540 kit available now. The factory system cost around $1200 but there is a kit available now for about $420 that only requires a 400 ignition rotor if you have a 520, or a 520 crank if you happened to have a 400. The info is in the July issue of Dirtbike. They tested a local shops 400 in Tyler and was scared of it's power.