Xr 628 Jetting

I've got a 92 Xr600 with the Xrs only 10.5 to1 piston 628 big bore kit and I am installing a pro circuit T4 silencer and would be very greatfull for ideas on jetting. It currently has a 160 main, and I am unsure of the needle position or pilot size. I did a search and the only result I can come up with is 162 main, 65 pilot with no needle position described.

My '98 628 with a Yosh exhaust normally needed anywhere from a 165 to a 168 depending on ambient temps and the altitude where I was riding. In Colorado at higher elevations, a 160 or a 162. A 68 pilot worked good, experimented with needle position, left it in the middle. I finally installed an Edelbrock and never went back to the stock carb.

I would love to get a edelbrock but my budget just does'nt allow, so I'll just have to make the old carb work. Here in North Eastern South Dakota we are at about 1500' so maybe I'll just try the 165 main with the 68 pilot and see what happens. I know it probably wont be exact but at least with you advice it gives me a good place to start. I have been riding in the Black Hills at 5000' and am kind of hoping for a happy medium that will run out there too. Thanks for the reply and any more input that you have would also be apreciated. Steve D

Mine was dez only and I ran a 68 pilot and a 168 main. Do you use the 628 plug? Boy that dog was not cheap.

Maybe I should try the 168 main first then. I didnt know there was a special plug is it worth using

I had the HRC kit in my 99 and it came with a new Honda manual, jetting specs and required a special HRC plug that ran about 20 bucks.

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