NCY Exhaust Jetting AF16

Does your Spree/Elite already run great, and you're trying to make it quicker/faster? Need a monster motor swap? Discuss your ideas here.

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nateberrier
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NCY Exhaust Jetting AF16

Post by nateberrier » Fri Sep 06, 2019 3:51 pm

I have an otherwise stock bike, grabbed an NCY pipe for it. I was curious if anyone has run the same thing and could give me a ballpark for jetting. Stock is 78. Someone said to go to 95 and work my way down but that seems like it might be a bit much lmao. I know that nobody can give me an exact number but yeah.

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Also if anyone has recommendations for keeping the stock airbox on that would be cool. this one keeps falling off and im just adding zipties
1986 Aero White -- Af16 Swap + Keli Var + NCY Pipe
1985 Aero Red -- Af05 Malossi BBK + Keli Var
1985 Aero Red -- Parts bike that will be fixed soon

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Meatball
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Re: NCY Exhaust Jetting AF16

Post by Meatball » Fri Sep 06, 2019 4:28 pm

95 and down sounds like sound advice. The stock box will stay put if you use the mounting bolts for it. One on the bracket below the carb and the other bolt goes into the mounting point casted into the case at the rear.
I need to find some new haters...the ones I have are starting to like me.

harleyracer59
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Re: NCY Exhaust Jetting AF16

Post by harleyracer59 » Fri Sep 06, 2019 6:53 pm

I agree. start rich and work your way stoich. your engine will thank you. lol
with stock air box stock cylinder and aftermarket exhaust, 90-95 sounds like a good starting point. you said it has a 78 stock? was the original muffler a restricted version? if it was, taking out the restrictor washer would probably move jetting towards 85ish. then going to your ncy exhaust will probably move you up to 90ish. those are just rough estimates, but you get the drift of where im going, I hope.
id try a 95 and work down easier on motor than say, 82/85 and working up. make rich test passes, lean test passes could result in a soft seize or worse.

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Meatball
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Re: NCY Exhaust Jetting AF16

Post by Meatball » Sat Sep 07, 2019 12:14 am

Let us know your progress and what jet you end up with. As more people buy these pipes, the question will be asked again.
I need to find some new haters...the ones I have are starting to like me.

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nateberrier
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Re: NCY Exhaust Jetting AF16

Post by nateberrier » Mon Sep 09, 2019 3:17 pm

harleyracer59 wrote:
Fri Sep 06, 2019 6:53 pm
I agree. start rich and work your way stoich. your engine will thank you. lol
with stock air box stock cylinder and aftermarket exhaust, 90-95 sounds like a good starting point. you said it has a 78 stock? was the original muffler a restricted version? if it was, taking out the restrictor washer would probably move jetting towards 85ish. then going to your ncy exhaust will probably move you up to 90ish. those are just rough estimates, but you get the drift of where im going, I hope.
id try a 95 and work down easier on motor than say, 82/85 and working up. make rich test passes, lean test passes could result in a soft seize or worse.
78 is stock for the unrestricted motor. Someone ditched their restricted pipe on this bike. Someone on facebook said 84 is probably close for this combo, I put in an 88 just to be safe and its definitely not lean with that. I will try to jet this week. I was going to chop at 88 and if its rich go down from there, but i probably should focus on cleaning the carbon buildup out of the exhaust port first.
1986 Aero White -- Af16 Swap + Keli Var + NCY Pipe
1985 Aero Red -- Af05 Malossi BBK + Keli Var
1985 Aero Red -- Parts bike that will be fixed soon

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