jetting for a Vance an hines exhaust 1977 kz 1000

I want to go from a stock exhaust to a vance and hines 4 into one exhaust. Does anyone know what kind of jetting that I will need to change? The engine is a 1075cc also, the carbs are stock with a stock airbox.

You may not need to make any jetting changes. Not all exhaust changes require jet changes. Changes to air intake are more likely to require jet changes.

When I was running vm26's with pods on my 1105 I believe I was running #20 pilots #120 mains with the needle on the 3rd clip to my best recolection. I'm at sea level near Daytona Beach. Hope this helps.

If it ran fine before, it will likely run fine without any jetting adjustments - but for MAYBE a slight adjustment to the mixture/air screws.

Good luck.

The 76 KZ900 carb jetting specs are just about perfect for an air box pipe with a 4-1. Mains are 115, cant recall off hand what the pilots are. This is the combo that Superbike Mike in Ft Lauderdale Fl. used to build my KZ900 10.25-1 1105 wirh 395 lift 260/260 shim on top cams & a street ported head. It hauled butt in 1978 and still does

Pu the pipe on and a new set of plugs and see what happens. I put on a kerker and it ran a little lean. Not enough for a jet change I just fattened it up a little and it's fine.