The carbs were bought for my honda CB/SL35O project. But are to big for the stock head to tune in. The CB is actually 325cc so if you break it down the cc per cylinder is 165cc. So I believe if you ran these on maybe a XL175 or a 200 you'd be pretty close to the mark & to be honest, I don't want to pull the carbies apart to check jets and so on, as they are unmolested. So if your keen let me know & thanks. jimson