2004LEBanshee Posted August 24, 2012 Report Share Posted August 24, 2012 (edited) 421 F.A.S.T. ported serval, PWK 35's, Nology coil wires. +4, K&N pods, VF3 Reeds This thing was running crappy (sputtering up top and sometimes down low) until I dropped the main from a 155 to a 152, 45 Pilot, 2.5 turns out. CEL middle clip. Runs pretty good now just seems like this is pretty lean compared to others on this site. My only problem now is I think the pilot is a little big some how. When it starts cold I dont need to hit the throttle but when warm I need to hit the throttle to get it to start. I also did a plug chop with 155 and the chop looks the same but the bike does not rev near as clean. Is it possible it just likes a leaner pilot then most or are a lot of people on here off with there jetting. Opinions. Edited August 24, 2012 by 2004LEBanshee Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted August 24, 2012 Report Share Posted August 24, 2012 I just won the 0-450cc class at the National Hillclimb on a FAST 421 Serval. Rocket pipes, 35PWK, pods and +4 timing. 160 mains and 48 pilots. Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted August 24, 2012 Report Share Posted August 24, 2012 Sounds about right but I bet you are slightly rich on the needle. Just remember to check the main again if you move a clip or two. If I had to guess its needle position. Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted August 24, 2012 Report Share Posted August 24, 2012 Having to hit the throttle to start when warm is usually because it is rich on the low circuit. You may need a smaller pilot as well as check the needle. I do half throttle chops but I like to keep it a little fatter on the needle than what your mainjet chop looks like. I would bet it is pretty fat with the cel needle in the middle especially if you have a midrange pipe. Quote Link to comment Share on other sites More sharing options...
2004LEBanshee Posted August 24, 2012 Author Report Share Posted August 24, 2012 Sorry forgot to include I'm running shearer inframes. Seem to low on the main but I think the chop looks good and it runs like crap with a higher jet. I might. Try one smaller pilot and bump the main up. Quote Link to comment Share on other sites More sharing options...
SuperMex Posted August 24, 2012 Report Share Posted August 24, 2012 Whats your elevation? Quote Link to comment Share on other sites More sharing options...
2004LEBanshee Posted August 24, 2012 Author Report Share Posted August 24, 2012 1000 ft Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted August 25, 2012 Report Share Posted August 25, 2012 Something isn't right. You shouldn't be that far off in jetting. Our elevations are the same and mine starts, idles and runs perfectly. Quote Link to comment Share on other sites More sharing options...
guns4children Posted August 25, 2012 Report Share Posted August 25, 2012 I'm running 48p 160m cel 1 clip up. + 6 timing. Quote Link to comment Share on other sites More sharing options...
Rustynail Posted August 25, 2012 Report Share Posted August 25, 2012 I'm running 48p 160m cel 1 clip up. + 6 timing. But your doing 3/4 throttle plug chops Quote Link to comment Share on other sites More sharing options...
2004LEBanshee Posted August 25, 2012 Author Report Share Posted August 25, 2012 I could never run those jets. I don't know what could be wrong. Oem cdi oem stator all check fine had an oem coil a few weeks ago and same thing Quote Link to comment Share on other sites More sharing options...
dozer Posted August 25, 2012 Report Share Posted August 25, 2012 on my 421 serval im running 35 pwks 160 mains 48 pilots cel needle in the middle clip. i also have the nology coil and wires with shearer inframes. very easy to start on the first kick, hot or cold. Quote Link to comment Share on other sites More sharing options...
2004LEBanshee Posted August 25, 2012 Author Report Share Posted August 25, 2012 My previous motor was a stock cylinder FAST 4 mill play port. It seemed to run smaller jets then everyone elses as well. Mine ran real strong so I just figured there was nothing wrong 5 years no problems. For this build I put a new OEM Stator and an unlightened oem flywheel on but the carbs CDI and wire harness are the same. Its a differnt motor but still likes way leaner jets then anyone elses . To me the plug chop seems to look good. Im not sure if this is something I should keep chasing or its just the way mine is. Is is possible something is wrong with the carbs and they flow diffently? I purchased them new off FAST when I built the 4 mil stocker about 6 years ago. Quote Link to comment Share on other sites More sharing options...
2004LEBanshee Posted August 25, 2012 Author Report Share Posted August 25, 2012 I started today at 158 and a 48 and it was real boggy at all RPMS. It got better as I went down. Did the plug chop when I got to something that ran good. Quote Link to comment Share on other sites More sharing options...
2004LEBanshee Posted August 25, 2012 Author Report Share Posted August 25, 2012 Would a bad flywheel have symptoms that go away with leaner jetting? Quote Link to comment Share on other sites More sharing options...
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.