I just received one of these AFAM 16t sprockets in the mail and it is not a direct replacement.

The website says it is a fit for MC21/28 NSR250s, but the packaging has only 1980's models listed.

The inner teeth (or whatever they are called) are a slightly different. It will physically go on the shaft, but only with the help of a hammer.

Has anyone modified one of these to fit?