I replaced my old dual pipes with Siamese pipes and a straight thru Goldie exhaust, what an improvement in power!
Not a fair comparo I realize as the old left hand pipe had this huge crimp in the underside of the pipe. The bike is new to me and I hadn't spotted this restriction until removal of the oldpipes to fit the new.
I can leave the 23 tooth engine sprocket in place. Was about set to reinstall the 21 in order to retrieve a bit of power.
Glen