JasonsBanshee Posted February 12, 2014 Report Posted February 12, 2014 I've searched and searched with no luck. I'm setting up my carbs for my new cub motor. So far I have 168 mains 52 pilots clip on the 4th on the CEL needles air screws out 1 full turn from seated But where should I start the idle screw at? Of course once I get it fired up, I'll sync the carbs and adjust the idle accordingly, but I need to know where to start. Thanks! --- Specs that affect jetting (if it even matters for the idle adjustment) 800 feet above sea level in frame shearer 35mm PWK clamp on K&Ns VF4 ported cub Quote
Strm Trpr Posted February 12, 2014 Report Posted February 12, 2014 I have no idea about 35mm PWK's, but from my knowledge of setting up stock carbs, I would imagine while holding the carb in your hand and looking at the slide from the filter, you would screw in the idle screw until it touches the slide and moves the slide up 1mm or so, maybe a touch less? Experts? Quote
JasonsBanshee Posted February 12, 2014 Author Report Posted February 12, 2014 Okay that makes sense. The process is probably about the same for all carbs. I have a sync tool and will adjust the idle once I fire it up so this should get me to a good starting point. Quote
SAVAGE420 Posted February 12, 2014 Report Posted February 12, 2014 I have no idea about 35mm PWK's, but from my knowledge of setting up stock carbs, I would imagine while holding the carb in your hand and looking at the slide from the filter, you would screw in the idle screw until it touches the slide and moves the slide up 1mm or so, maybe a touch less? Experts? I do the same thing, then once fired up and warm, dial it all in once and for all. Quote
Strm Trpr Posted February 12, 2014 Report Posted February 12, 2014 I do the same thing, then once fired up and warm, dial it all in once and for all. Cool, thanks for verifying what I thought seemed logical. Quote
JasonsBanshee Posted February 12, 2014 Author Report Posted February 12, 2014 Do you guys put anything on the threads to help it from moving on it's own? I noticed some teflon or something on the threads from the previous owner. Quote
Strm Trpr Posted February 12, 2014 Report Posted February 12, 2014 Stock carb idle screws have a lock nut. And I also use blue lock tight. It breaks free, and then they do not loosen by themselves. In this link, there is an exploded view. http://www.keihincarbs.com/tips/gate.html Item 4 is the idle screw. By what I see, there should be a spring that doesn't allow the idle screw to loosen. Do you have the spring too? Quote
SAVAGE420 Posted February 12, 2014 Report Posted February 12, 2014 I use metal idle screws and spring in my 35's, always stay where I put them. The lighter springs are nice as well. Also use the longer adjusters up on the caps, for all of it is a few extra bux, so why not! I use all of this...just think Jason, now you WILL call Jeff again right now and get them hahaha. http://www.farmandsandtoys.com/partdetail.asp?partid=119 Quote
JasonsBanshee Posted February 12, 2014 Author Report Posted February 12, 2014 Yea I have the springs. I have the extended adjusters too. Sent from my SCH-I545 using Tapatalk Quote
SAVAGE420 Posted February 13, 2014 Report Posted February 13, 2014 Well hurry along and get the metal screws....just for shits and grins anyway. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.