Their is no set standard for jetting. It depends on temperature, altitude and humidity.
Here in Vegas we can install an 82cc BBr big bore kit on our bikes and not rejet. They are so rich from the factory stock up here that we can do quite a bit without worrying about running lean.
To answer the question if it comes with a just the answer is NO. This pipe works great on stock to 88cc bikes and its not obnoxiously loud for the power you get. If you have heard a white brothers exhaust it is very close to it.
The muffler on this pipe is fairly short as well so it tucks behinjd the number plates good.
I just installed my Dr.D pipe on my stock motor.Stock main jet, just went one step richer on the needle and it runs great.I'm at sea level,temp. around fifty.Its a nice pipe,sounds great and should'nt bug my neighbors too much.We'll see how it works once my motors done up. Ordered it through holeshot motorsports by the way.Great people to deal with no b.s.
I did notice a slight perf. gain but nothing drastic though.I got the pipe before doing the motor just cause i hadnt decided which way i was going on the motor.I decided on this pipe cause its what i was looking for, stock or modified,its light,nicely made and not too loud.Its good for low-mid range but if youre looking for a top end pipe youd be better off with a classic honda or two brothers.Too loud for my neighborhood!!Ive got an 88 high compr.kit and ported 70 head coming from PRC and brian told me this pipe should work fine for what i'm looking for.I cant wait to get these parts later this week.I'll let you know how it rips. The pipe was $190 shipped to my door from holeshot and is well worth it. :lol: