PDA

View Full Version : another 250r jetting question



jimeeatc
10-08-2007, 08:46 AM
just curious if anyone has gone to leaner than stock on pilot/main for 85/86 r with or without mods? i ask since factory jetting is supposedly on the rich side. maybe a stupid question but thought i would ask anyway. anyone ever have to do this to achieve max results?

Liquid-Darkness
10-08-2007, 09:18 AM
At one time I thought jetting a bit lean was working for me. I found out that I needed a few mods and to jet up at least 4 over sizes on the main jet. The pilot I got now is actually a 50, stock is a 52. I am only using a 50 because its the only jet the store had that would fit a PWK. When jetting a bit lean, the bike may seem to run faster, but is not good for the engine. A stock bike should be fine with stock jetting, maybe 1 or 2 richer. I say if you are trying to lean out your throttle, drop your needle or open the mix screw no more then 3 turns out. Can't starve these two strokes for fuel, they get hot quick.

jeffatc250r
10-08-2007, 12:34 PM
Go to duncan racing website, they have a keihin step for step jetting guide. If your still confused and dont know what to do i say cough up some money and bring it to a good shop and have them tune it in for you. Ya it sucks to spend money, but if you screw up and lean it out too much and cause a seizure it will cost you a lot more. Not only that but its like night and day power wise when everything is dialed right in.