balancing pilot screws

paulson_shawn · Posted: July 12, 2007, 6:45 pm Post subject: balancing pilot screws

is it a bad thing to have my left screw 2 turns out and my right one 3 out to balance the cylenders, or can i keep them that way?

grizld1 · Posted: July 12, 2007, 11:49 pm Post subject: Re: balancing pilot screws

You don't "balance" with the pilot screws, you set each one individually for highest idle then balance with the synch screw in the middle of the throttle shaft. If one side requires a full turn more than the other to find highest idle, that could indicate that one of the jets was either partially plugged or hogged out, that a pilot air intake was plugged, or that a pilot fuel passage was obstructed. Sometimes it takes more than one try to get everything clean.

paulson_shawn · Posted: July 13, 2007, 1:06 am Post subject: Re: balancing pilot screws

they're brand new jets so i pulled the carbs and i'll get a gallon cleaning kit tommorow. i just used carb cleaner spry can before. if u sync with that screw in the muddle of the shaft is one butterfly not going to be all the way open at WOT?

INXS650 · 650Rider Supporter Joined: Mar 22, 2007 Posts: 645

If they are properly synced, both should open the same amount at the same time, thus syncronized. These carbs can never be clean enough.

grizld1 · Posted: July 13, 2007, 9:59 am Post subject: Re: balancing pilot screws

Be sure not to soak the carb bodies. There are rubber seals on the throttle shafts and you don't want to damage them. Use spray-in cleaner and compressed air to blow the passages in the carb bodies clear, probing gently with fine wire if necessary.

paulson_shawn · Posted: July 13, 2007, 4:53 pm Post subject: Re: balancing pilot screws

i just put the bodies in to soak and then got online to read this. i gotta get them out now

paulson_shawn · Posted: July 14, 2007, 2:18 am Post subject: Re: balancing pilot screws

ok. i took the one carb body i had soaking and rinsed it with the garden hose and blew it dry with the air compressor, then i cleaned everything but the float bowls, choke bodies, and needle jets and needles (i did soak them) with spray cleaner and elbow grease. saw that when my carb bodies were really clean that my needle jet o-rings weren't sealing tight so i replaced them. carbs are spotless and back on the bike with 142.5 MJ's and 30 PJ's to start with. (also have 140, 145 MJ's and 35 PJ if those don't work out). my new reg/rect showed up today so i'll put that on tommorow and test ride / tune. i think maybe the worn o-rings might have caused a lean situation since the fuel level is below that point?

paulson_shawn · Posted: July 15, 2007, 5:41 pm Post subject: Re: balancing pilot screws

finally got my carbs set right. pulls good from idle to redline, no stumbles. i had some vacume leaks when i first tried the same set up i'm at now, so i was trying to run too big of jets. Ended up running 1 up on the pilots, 2 up on the mains, and raised the needles 1 notch, 2 turns out on pilot screws. and it runs sweet. pulls smoothly from idle to 9000 (could,t get over 6000 before and it ran like sh*t from 4000 on ). i tried all the combinations with 27.5,30,and 35 PJ's , 137.5,140,142.5,145 MJ's and needle heights and ended up at exactly what grizld1 suggested. that's pretty kool ! Thanks for the help.

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