PMS adjustment or jetting?

[Bmblank]

Hello, I’m new to the forum. So glad to have found a place with so many great posts and knowledgeable people. So, I’m just curious if I need to re-jet or just rich up my fuel/air ratio? The issue is with my 2001 road star 1600. I have Cobra long tube exhaust and a RK-3905-1 K&N full circumference intake. Seems a bit lean after putting on the exhaust (backfiring on decel, could be AIS as that is still hooked up?) and was un-rideable with the K&N intake. I couldn’t get above a certain rpm without choking out so I put the stock back on for now. I haven’t pulled apart the carb yet so don’t know the sizes yet but I assume they are original. Are larger jets necessary or can I just fatten up the fuel/air with PMS adjustment?

Thanks, Bryan

[davej]

First thing is to remove the AIS, You should rejet. Get a Barons kit and no other brand. You should install a 167.5 main jet and a 37.5 pilot jet. The pilot jet would need to be purchased separate from the kit. then put the clip in the 4th groove down from the flat end on the Barons needle with the plastic spacer and 1 silver shim under the clip. Set the PMS at 2 1/2 turns out and you should be spot on with the jetting.

[Father Pobasturd]

Yea, what he said. Take a look at the Coasting Enrichener while you're messing with the carb. If it's the original one, It's probably all yellow lookin' and possibly cracked. If it's not cracked, it's only a matter of time. It will. Replace it with a machined aluminum one which you buy on this site. If cracked, it will cause lots of popping on decel. Not saying that's your current issue, might be, but more likely the AIS.

[Mr. Miyagi]

From Texarkana, in the Arklatex

[SbTx_Rider]

From Spring Branch, Texas

[Bmblank]

First thing is to remove the AIS, You should rejet. Get a Barons kit and no other brand. You should install a 167.5 main jet and a 37.5 pilot jet. The pilot jet would need to be purchased separate from the kit. then put the clip in the 4th groove down from the flat end on the Barons needle with the plastic spacer and 1 silver shim under the clip. Set the PMS at 2 1/2 turns out and you should be spot on with the jetting.

Awesome, thank you for the help! (And so quickly)
I’ll get to ordering now. You guys rock

[Bmblank]

davej Is the 167.5 still recommended if I have aftermarket pipes without baffles? The install sheet says 172.5 with that set up

[Brad_G]

from Solon, IA

[davej]

If you are gonna run without baffles use a 170 main jet not a 172.5. running without baffles you may never get rid of decel popping. and you will lose a bunch of torque. for some unknown reason Barons has use 2 different sets of directions and the one you posted is not the one that is used by most in this group. Those directions show 1 size larger than needed in all of the configurations.

[Engineman]

from Keeseville, NY

[Kevstephenson7]

Useful info Dave
i was going to order a barons kit but now cannot order direct from them. Pacific coastar offer the dynojet kit for roadstars; is this kit ok to use too?
i think Back in the day I used a 172.5 on mine. It used to be in my settings on here which disappeared on here so I have no real record.
any advice would be welcome Dave and also

[davej]

I would try to get a Barons kit. The Dyno kit does not use Mikuni Jets and the needle has a different taper and length so the jetting would be a little of kilter using the dyno kit. It will work in a pinch but not the preferred kit.

[Kevstephenson7]

Thanks as always Dave for your sage advice. I’m onto it