Jgspahn Posted August 30, 2013 Report Share Posted August 30, 2013 (edited) Ok I know there are a ton of help me jet threads, but I need the help too so here it is. Im gonna keep this thread alive through the whole process so I can ask my questions and post plug chop pics and that sort of thing. So, question 1. I need a baseline to start. Ill be breaking in the new motor and all that at this time too so I really need a good base to start on just to get the motor broken in. Here are my mods: Shaved head Stock Carbs bored to 27.5, tors deleted Pod Filters F.A.S.T play port +4 timing T5 Pipes VF2 reeds Its bored .40 Premium gas Also, what range of jets do I need to have on hand. I have 280, 300, 310 (currently in carbs), 340 mains.. and 27.5 pilots and whatever is in the carbs right now (I couldnt find a screw driver small enough to get it out today) Heeeeeeeeeeelp Edited August 30, 2013 by Jgspahn Quote Link to comment Share on other sites More sharing options...
Jgspahn Posted August 30, 2013 Author Report Share Posted August 30, 2013 I ride between 150 and 300 feet above sea level Quote Link to comment Share on other sites More sharing options...
Sandking Posted August 30, 2013 Report Share Posted August 30, 2013 Ask FAST they did the porting Quote Link to comment Share on other sites More sharing options...
apeik Posted August 30, 2013 Report Share Posted August 30, 2013 Asking jeff would be you're best bet if you wanna get it right in there, he's pretty cool and will help you out with whatever you need. For reference.. I had close to the same setup except fmf's and an HJR dune port, was at 27.5 pilots and 330 mains, at sea level. Quote Link to comment Share on other sites More sharing options...
Larry's Shee Posted August 30, 2013 Report Share Posted August 30, 2013 What did you add/change from the last set-up? Dry or humid? Avg riding temps? Quote Link to comment Share on other sites More sharing options...
Jgspahn Posted August 30, 2013 Author Report Share Posted August 30, 2013 Changes were........ Bored .1mm Timing Advance Port Job Head Shave avg riding temps around here are 80-100 (mfn hot!) right now.. its pretty humid down here in the south. Jeff is awesome and Im going to call him today. Ill report back afterwards. Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted August 30, 2013 Report Share Posted August 30, 2013 My aggressive dune ported 4mil motor is running 30 pilots and 350 mains FMF Golds, +7 timing, 19cc domes... It's jetted perfect, nice Hershey bar color on the plugs... I started at 330 mains and worked up until it was a little too rich and backed off 1 jet size... 360 was too rich.. I have mains from 280 -360 and pilots from 25-32.5 Quote Link to comment Share on other sites More sharing options...
Jgspahn Posted August 30, 2013 Author Report Share Posted August 30, 2013 Aight just got off the phone with Jeff. He is sending me some 320, and 330 jets. He said start at 340, 27.5, and needle clip in the middle and go from there.. he said I wouldnt need any higher than 340 and no higher than 27.5.. So looks like I have what I need to get started with the 340 and 27.5. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted August 30, 2013 Report Share Posted August 30, 2013 Considering your carbs are bored 1.5mm larger than stock, one should assume the motor will be ingesting more air, so I'd start off with the following jets: 30 pilots air screws turned out 1.5 turns, (all the way in requires next size up pilot, more than 3 turns out requires next size smaller pilot). stock needle middle clip 350 mains As far as jets go, get what Zillaguy recommended. Cascade http://www.cascadeinnovations.net/store/store_View.cfm?STORE_AREA_ID=13&store_dept_id=102 has a decent deal on jets, but cal Jeff at F.A.S.T. and see what he can do for you. 27.5 - 30 Pilot Jets 320 - 350 Main Jets Make sure and sync the carbs with the F.A.S.T. sync tool http://www.farmandsandtoys.com/partdetail.asp?partid=59 with your idle at around 1500 rpms. Then sync the carbs at around 5500 rpms. Be sure and put a fan blowing thru the rad so you don't get too hot and blow off coolant thru the overflow. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted August 30, 2013 Report Share Posted August 30, 2013 Aight just got off the phone with Jeff. He is sending me some 320, and 330 jets. He said start at 340, 27.5, and needle clip in the middle and go from there.. he said I wouldnt need any higher than 340 and no higher than 27.5.. So looks like I have what I need to get started with the 340 and 27.5. Did you mention to him that your carbs are bored out to 27.5mm? Quote Link to comment Share on other sites More sharing options...
Jgspahn Posted August 30, 2013 Author Report Share Posted August 30, 2013 Yea I did mention that to him. You made me nervous so I called back and added some 350main and 30 pilots,just in case. Quote Link to comment Share on other sites More sharing options...
Strm Trpr Posted August 30, 2013 Report Share Posted August 30, 2013 Hey man, I'm not sure what the effects of bored carbs are, but my gut tells me more air requires more fuel. Quote Link to comment Share on other sites More sharing options...
Jgspahn Posted September 12, 2013 Author Report Share Posted September 12, 2013 ok, here we go guys.. I have to get this thing jetted TONIGHT. I been staying at the shop till almost 3am trying to get this motor built and bike back together. Everything is done, all thats left is to jet it. Heres where im at: 340 mains 27.5 pilots You gotta give it gas to get it cranked... the left side carb is pouring gas outta the overflow.. it wont idle.. runs like shit till about half throttle.. runs great at 1/2 throttle.. about 3/4 throttle it starts cutting out again.. HEEEEELP me.. I have a big ride this weekend and I want to show off my bike thats been 2 years building Quote Link to comment Share on other sites More sharing options...
Colby Posted September 12, 2013 Report Share Posted September 12, 2013 float levels on the carbs need adjusted ... that will take care of the overflow try the 330 mains... look at your plugs, if they darker than a light brown, its too rich, if they are lighter than dark brown, too lean start with the air screws 1 1/2 turns out .. Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted September 12, 2013 Report Share Posted September 12, 2013 The carb is leaking fuel because either the needle and seat on the float is stuck, or the float level is too high. turn the fuel on and lightly tap on the carb bowl that is leaking if it's the needle and seat it will stop... if not you need to take it apart and see why it's leaking... should be obvious... try the 30 pilots, and 340 main.. set the pilot air screw at 1.5 turns out... Put the carbs back on the bike and sync them, then start the bike get it to idle first... You should be good from there unless you have air leaks... Do a few hard pulls once the motor is warmed up (20mins at least) Then pull your plugs and post a picture of them here. Quote Link to comment Share on other sites More sharing options...
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