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120 jet settings

Posted: Fri Nov 13, 2009 11:19 am
by CharlieK
I have recently received a set of 120 pilot jets from Rick Oliver and Im about to start overhauling my carbs. I wondered if anyone else is running 120s all round and what settings you have them at? The Hanus manual states two turns out from fully in for the standard jets, but can anyone offer me a starting point with these? The bike is running standard downpipes with a Viper oval race can. Cheers for any advice.

Re: 120 jet settings

Posted: Fri Nov 13, 2009 11:58 am
by CMSMJ1
I think you are getting slightly confused.
You will have 120 main jets which are different from pilot jets.

You install the jets so they seat in the emulsion tube.

then rebuild the carbs and run it

Re: 120 jet settings

Posted: Fri Nov 13, 2009 8:51 pm
by MexicanGringo
My nc30 carbs had 120s all round but were running way rich and fouling.. Is it a nc30 or 35? Why did you go for 120s? The haynes refers to 2 turns out for the pilot screw and the pilot jet size of an nc30 is 35

Re: 120 jet settings

Posted: Fri Nov 13, 2009 9:00 pm
by CharlieK
Ok so in short leave the pilot jets alone because that alters the fuelling, install the new main jets and away we go?

Re: 120 jet settings

Posted: Fri Nov 13, 2009 9:58 pm
by Neosophist
CharlieK wrote:Ok so in short leave the pilot jets alone because that alters the fuelling, install the new main jets and away we go?
Ok ok... you have 3 things.

Main Jet: #1xx
Pilot Jet: #35
Pilot Screw: Adjustable in turns.

You'll be changing the mains. The pilot jet (35) is usually fine for most purposes.

You may get a better idle adjusting the pilot screw but make a note of the stock setting so you can reset it to what it was before fettling should something go wrong ;)

Re: 120 jet settings

Posted: Sat Nov 14, 2009 6:59 am
by banoffee
is it an NC30?

Re: 120 jet settings

Posted: Tue Nov 24, 2009 5:37 pm
by CharlieK
Banoffe, sorry I have been away for a week, yes its an NC30 a 93 model, and yes im not that familiar with carbs so any advice is appreciated. C

Re: 120 jet settings

Posted: Wed Nov 25, 2009 9:57 pm
by furryfrog
What mods does the bike have?

Re: 120 jet settings

Posted: Thu Nov 26, 2009 7:03 pm
by CharlieK
Its Standard other than an oval Viper end can.

Re: 120 jet settings

Posted: Thu Nov 26, 2009 8:23 pm
by royster81
120's a bit high for just a can me thinks

i was running 120's with a twin stack half system,FI needles and new stock filter.