Originally Posted by pastorbobnlnh

No problem Jim.

Just take 19T and 23T cogs and file away half a tooth. I do this at the Spa for fanatical gear heads.

This is a premium service because I shape the tooth in a specific way in order to "trick" the chain and the RD to shrink by the specific percentage in order to achieve the specific gear inches which do not duplicate. It takes great skill and patience to achieve the desired profile and shape. The cost can run between $200 and $300 per tooth.