N20addiction Posted February 23, 2014 Report Posted February 23, 2014 Okay so i have a 2002 shee stock bore, no port, fmf fattys, +5 timing, stock carbs, individual filters, and a boost bottle, my question is when i start the bike it idles fine with choke on and i can kinda rev it a lil then it falls on its face, with choke off it idles somewhat high and if i rev it it falls on its face instantly, does anyone know what would cause this? Quote
sleeper06 Posted February 23, 2014 Report Posted February 23, 2014 What jets r in it now need more info Quote
uman1030 Posted February 23, 2014 Report Posted February 23, 2014 What jets r in it now need more info ↑ this, + the mods you have listed require re jetting to a much richer fuel mixture so if that hasn't been done that is the problem. the symptoms listed are those of running too lean and running out of fuel as well as the high idle which is also a symptom of leaness. Not sure where you live and your temp but cold weather also requires a richer mixture so all this compounded may likely be the issue. riding it like this will cause engine damage. Quote
Zillaguy Posted February 23, 2014 Report Posted February 23, 2014 Boost bottle could have torn the intake boots... Causing a lean condition, which is why it "kinda" runs ok with the supplemental fuel from the choke circuit... Did it run good before? Quote
N20addiction Posted February 23, 2014 Author Report Posted February 23, 2014 I will check the jets in the morning, when i got the bike it ran like hell! (by the way The area where i bought it was 3500ft above sea level and where i live is 100 below sea level, ive never rode it where i live till now) but shortly after buying it i tore it down because it needed rings and a clutch and i rebuilt the carbs, but i did not mark where the air fuel mix was set, the carbs are synced, i left the tors idle screws alone, i did not mess with the needle clips, it still has the same jets as before so im not sure what my issue is other than the air fuel mix; i have it at 3 turns out. And i mix my fuel 32:1 ratio, normal temps around here are 70º to 90º Quote
N20addiction Posted February 23, 2014 Author Report Posted February 23, 2014 Also i really appreciate your guys help ive been trying to get it to run right for a month now, just terrible with carbs i guess lol Quote
uman1030 Posted February 23, 2014 Report Posted February 23, 2014 If your bike was jetted for 3500ft asl then when you moved to almost sea level it needs more fuel to compensate for the thicker air. You will need to increase the pilot and main jets. Also 3 turns out is too far out you should shoot for around 1.5 adjusting pilot to keep you around there. Opening the air screw leans the carb. If you have to be at more then 2.5 out to have a crisp responsive throttle you need a smaller pilot. Less then 1 you should increase the pilot size. At your altitude and mods I suggest you start with a 30 pilot, 300 or 310 main, clip stock position a/f screws 1.5 to start. Invest in the tors elimination kit w/idle screws. 2 Quote
WINDYCITYJOHN400 Posted February 23, 2014 Report Posted February 23, 2014 ^^^^ Great info and good starting point. Quote
sleeper06 Posted February 23, 2014 Report Posted February 23, 2014 If you rebuilt the carbs make sure the bowls are on the correct side and choke tube is in swapping bowls will give you a hard srart Quote
N20addiction Posted February 23, 2014 Author Report Posted February 23, 2014 Just checked the jets and they are 300 Quote
uman1030 Posted February 23, 2014 Report Posted February 23, 2014 Just checked the jets and they are 300 And the pilots were? slides installed on correct side with the cutaway toward the air filter? Quote
N20addiction Posted February 25, 2014 Author Report Posted February 25, 2014 Slides are correct and main jets 300, pilots said 1.4 and im not positive which bowl goes to which carb Quote
wayne_smith97 Posted February 25, 2014 Report Posted February 25, 2014 The bowl with the bb goes on left carb. Quote
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