I believe I was told by Ken some time ago (or have read his stuff) that if the pms screw was above the float bowl it adjusted air and if the pms screw was below it adjusted fuel. I take it that not all R* have the same carb.

please fill me in.<br><br>Post edited by: draco, at: 2006/03/28 19:52

The 1600 and 1700 have same 40mm mikuni, the 1700 is wearing larger jets.

This will answer your other questions and more, the straight goods from Mikuni, pretty close to the Road Star model .

http://www.mikuni.com/pdf/hs40_manual.pdf<br><br>Post edited by: Motostar, at: 2006/03/28 21:03

Thanks Motostar, how bout that pms screw? fuel or air?

I figured they had the same carb but wasn't sure, I must of miss read my question somewhere or miss understood what I was reading. If the pms was screwed all the way in would suck air and out would be fuel. Hmmm... again thanks for your time.

I always find a complicated way to explain things in my limited view, LOL, but let's eliminate the easy assumptions,

Its one or the other uummm..Let's make the assumption what if it is an air screw ? you would expect if it was that when the screw is turned in, it would reduce the amount of air and richen the mixture. If it is turned out, it opens the passage more and allows more air into the circuit which results in a leaner mixture.

We know that the R* carb pms causes a leaner condition when you turn it in and richer turning out contrary to the 1st assumption above, so that suggests the pms
permits more vaccuum in the circuit when you &quot;turn it out&quot; to draw more fuel from the bowl thus enrichening the mixture and less vaccuum when &quot;turned in&quot; leaning out the mix . Air or fuel ?? <br><br>Post edited by: Motostar, at: 2006/03/29 20:52

I think motostar is right on. The pilot air jet that works in conjunction with the PMS is located on the front face of the carburetor (part the air box hooks up to). It's replaceable with different sizes and can affect the gas/air mixture primarily in the idle to quarter throttle range. There's a picture of the pilot air jet in the Technical Tips section of this clinic at http://roadstarclinic.com/content/view/60/96/