I have a broken Cannondale 2007 Bad Boy Ultra, will the Promax Headset Adapter 1", 1-1/8" give me the opportunity to replace it with a non-shock standard fork.

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No, not at all. That is for converting a 1-1/8" frame to 1". In SHIS terms it reduces the headtube bore of an EC34 frame to EC30 (bore ID 33.8mm to 30mm). Headshok frames essentially use the EC49 bore top and bottom, other than the handful that take the bearing directly and don't use a cup (which I don't think this bike is). You need a headset reducer that's built to adapt to whatever type of steerer you're going to run, which unless you're doing something weird is either going to be tapered or 1-1/8".

Cannondale has used two different press bore depths over time and so you also need to get that part right.

If you know you want a non-suspension fork, you start this process on a Headshok conversion by figuring out what you want the new effective axle-to-crown to be. Headshoks have funny axle-to-crown numbers that typically can't be recreated directly. The typical scenario is the stock axle-to-crown is very long compared to the rigid forks available. You need to decide whether you would like the new fork to emulate the old one locked out vs at some point in the travel. Typically you'll need some amount of headtube/crown extension either way, and you want to get it using the smallest number of extra parts possible. In other words there are reducer headsets that have some amount of headtube extension built in, and normal ones that don't, and there are also standalone headtube/crown extenders. You want to end up with the least possible amount of "double-adapting," which you'll only be able to do after figuring out a target axle-to-crown.

This page has some more good info.

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