UNi Jetting???

[Foxnake42]

Threw a uni on, and was wondering if it was need of jetting or if it's just the coldness on NH.???? She sputters and a little backfire when first started.

[Stunz]

What happens after the motor warms up?

I doubt you will need to jet it with just a filter. If you were going to jet it for the colder weather, then you might want to go with a 150 main.

[jb400exxx]

try a 150 keihn main jet.

[Foxnake42]

I am still in the break in period, so this might make some sense. I tries to start it ans start it and she didn't even really catch for a bit. Finally it was sputtering and it took a lnog time to warm up, then it was running great. But it took so long that the battery was almost dead. Hmmmmmm.:macho

[cals400ex]

try a bigger pilot jet. this will help for starting. the stock is a 38. most people recommend a 42 or a 45. i have a 42 and it does not start much better than it did when stock, but it will always start. i also moved the clip down on the needle so the bike ran a little richer. this eliminated all sputtering when the bike was cold. as for starting, if you don't want to buy a new pilot jet you can try to come out with the fuel skrew on the bottom of the carb. this may not be enough so you may need the different pilot anyways. as for the jetting, i would put a 150 in the winter for sure. it may even run better with the 150 in the summer also. i am not sure how lean the mainjet was from the factory. i run a 152 with good success with only having a modded airbox lid. also, when starting the bike pump the throttle 4 or 5 times before you try to start the bike. this will pump some fuel in. don't do it too much and flood the bike though. also replace the plug if it is old. the stock plug is a DPR8Z.

[flyin#5]

i have the same problem with my 200. i put on the uni and she backfires and sputters a bit especially when coming down from top speed. im just going to try and adjust the valves first but if that doesnt work im going to rejet.