Senzo offer a range of tools for Rotax Max 125cc EVO and old style engines. The first, and the one that actually saves you money, is the slide and needle protector. Not having one of these to protect your engine during transport is simply madness; when the slide is hanging off the engine the needle at least is going to get bent. 3 needles is the same price of the protector!
Secondly is the simple yet most effective tool. The Senzo Jet Driver. It makes life easier and stops you cross threading the jet. These are specifically designed for a Dellorto jet so it'll unscrew it while gripping onto it using the inner o-ring and you pull it out with no hassle at all.
Another simple tool is the clutch holder. It keeps the plate in place while you do work with the clutch. Necessary for any mechanic's tool box.
A few other additional parts are available here.