Anyone running Keihin PWK's?

[ECshee]

So the temperate has radically dropped recently, and especially out of state. I was running 160 mains and 50 pilots for the summer-ish weather(august, after the new topend and mods were put on). The temp was roughly 70-90* and im experiencing weather from the upper 40's to 65 degrees now. if this a large enough change to warrant rejetting? Also, will riding in a location 700 feet above me, which is sea level, have any effect on jetting, or does it have to be a severe alttitude change. Thanks

[jbooker82]

I would run it to see how it is. You might have been over rich in the warmer temps.

[rdzbangshee]

you can run the stock air box cover either upside down or rite side up to change the mixture a tad to if your running more than fifty hp you my bigger carbs

[Darthwall]

it will change a bit but I wouldn't do anything wait until it gets cold and take it out see what happens

[trickedcarbine]

Well, I don't wanna sound like a dick, but there are a few folks who obviously would be asking for a new topend or they could give a shit less about whether your motor runs or not. C'mon guys! You are really gonna tella a guy to just run his bike in the cold and see what happens with out even finding out how it's current tune is? Pretty fucked up.

 

Anyway ec, how was the warmer weather tune? Yeah a 160 sounds a bit rich to me in those temps, even on a pretty built bike. The only way to be sure is pull the plugs and see how they look. If they are tan, you're close. Now decide if the tan is more dry and chalky or if it is a bit more moist. If they are on the moist side you are ok to ride in a little bit cooler temps. If they are on the chalky side bump the main up just a cunt hair. Maybe put the needle clip down one spot as well. The pilot should usually be ok unless you had it as lean as it can be. Try seeing if it runs better on the bottom with the air screw turned in a turn or two. If so give it just a little bit more pilot.