PDA

View Full Version : jetting help



riggsracin
09-26-2010, 06:58 PM
have a 86 r with a 85 20 over cylinder wiht a honda piston and radvalve and 2 stage reeds and a fmf sst with power core cylincer and 175 psi. what should jetting b? stock carb. now it 148 with a 42

09-27-2010, 10:28 AM
I am assuming you made changes to the engine package and the 148/42 was prior to these changes.

You are asking what your jetting should now be based on description. Also I will assume that you are located at an elevation of 0-1000ft, temp range of 60-90 degrees and you run pump gas with an octane rating around 92, with a non ported cylinder…

First make sure your carburetor is cleaned out, float level is set correctly, needle is shutting fuel off and the slide works smoothly.

I would start with 165/48 or even 170/50, needle clip 3rd-4th grove down from the top, air screw 2 turns out…this set up will be rich with a stock carburetor, however; I would error on the rich side; test ride and reject leaner as needed.

Look at your plug & exhaust temperature and jet accordingly…

Carlos.