Strm Trpr Posted April 21, 2016 Report Share Posted April 21, 2016 So, I sold my stock carb set-up in favor of the 33mm PWK's for my future Serval build. What jets and needles do you recommend with the following mods: 33mm Keihin PWK's w/K&N's and Outerwears UPP Intakes w/cross-over tube VF4's Mull Pump Gas Head +4* timing 91 octane w/YamaLube 2R mixed 40:1 stock pistons stock port CPI pipes Sea level in Pismo 75-80* F What pilot? What needle? What main? Stock 33mm PWK's come with the following: 52 pilots CGL needle 165 main jet I talked to a shop and they mentioned the following to start: 48-50 pilots CGL or CEL needles 155 mains Thoughts? Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted April 21, 2016 Report Share Posted April 21, 2016 160 main 48 pilot CEL needle on middle clip Air screw .5 out Tune the pilot first. Make sure it starts and idles. Make sure you don't have any lean hang. Then go ride it. Couple WOT plug checks. Adjust accordingly. Then adjust needle if needed. Then fine tune air screw. That's how I'd do it anyway. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted April 21, 2016 Author Report Share Posted April 21, 2016 160 main 48 pilot CEL needle on middle clip Air screw .5 out Tune the pilot first. Make sure it starts and idles. Make sure you don't have any lean hang. Then go ride it. Couple WOT plug checks. Adjust accordingly. Then adjust needle if needed. Then fine tune air screw. That's how I'd do it anyway. Nice, do you think I should buy the following jets and needles. 48 and 50 pilots CEL Needle 150-152 and 158-160 mains Lean hang? Is that when you stab the throttle and the engine wants to stay rev'd and wont decelerate? The airscrews on 33's are on the air inlet side of the throttle slide correct? If so, then they'd tune like stock carbs and .5 turns out from seated means rich and I should expect to turn them out to crispen the off idle throttle snap? Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted April 21, 2016 Report Share Posted April 21, 2016 Nice, do you think I should buy the following jets and needles. 48 and 50 pilots CEL Needle 150-152 and 158-160 mains Lean hang? Is that when you stab the throttle and the engine wants to stay rev'd and wont decelerate? The airscrews on 33's are on the air inlet side of the throttle slide correct? If so, then they'd tune like stock carbs and .5 turns out from seated means rich and I should expect to turn them out to crispen the off idle throttle snap? I have a wide variety of jets.. But 158-162 should cover anything you will encounter, even with a bigger motor. Yes, a lean hang is when it won't return to idle. Yes, adjust the air screws to make it rev out clean. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted April 21, 2016 Author Report Share Posted April 21, 2016 Awesome, thanks for that!! OK, so let's say my motor at sea level is running 48 pilots, CEL's middle groove, 160 mains and airscrews 1.5 turns out. What would you recommend my changes be with these same mods for riding at 4,000 ft? Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted April 21, 2016 Report Share Posted April 21, 2016 What's the difference from the first post? Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted April 21, 2016 Author Report Share Posted April 21, 2016 Mods, nothing. Elevation from sea level to 4,000 ft. I just want to stay on the same page. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted April 22, 2016 Author Report Share Posted April 22, 2016 Still need more info. sleeper06, where you at? Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted April 22, 2016 Author Report Share Posted April 22, 2016 OK, so let's say my motor at sea level is running 48 pilots, CEL's middle groove, 160 mains and airscrews 1.5 turns out. What would you recommend my changes be with these same mods for riding at 4,000 ft? Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted April 22, 2016 Report Share Posted April 22, 2016 I'd say 4-5 main sizes and a couple pilot sizes. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted May 23, 2016 Author Report Share Posted May 23, 2016 I idle tuned the 33mm Keihin PWK's in about 15 mins.48 pilots w/Airscrews 1.5 turns outCEL needle middle groove155 mains idle set to 1,500rpms w/eBay tach and carbs sync'd at idle with FAST sync tool.Cold kicking compression is 150psi w/Pump Gas Mull Head Part throttle sync to be done Wed after I get a new throttle cable, then plug chop. When plug chop looks good, I'm going to add 4* of timing and chop again.If that looks good I'm going to lean the needle 1 groove to see what happens with a plug chop. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted May 26, 2016 Author Report Share Posted May 26, 2016 Bike fires up 1st kick without choke when it's cold, so that's good. airscrews 1.5 turns out. 48 pilot After a plug chop revealed a slight leaness, I fattened the CEL needles and put the clip on the 4th groove. I'm going to go from 155 to 160 mains and rechop. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted May 31, 2016 Author Report Share Posted May 31, 2016 So, I ended up running the following: 48 pilots, airscrews 2 turns out CEL needles, 4th groove 160 mains Bike ran like a top all weekend!! Quote Link to comment Share on other sites More sharing options...
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