How’s it going fellas,
Down to the last leg of the project, and that’s getting my chikuni 22mm tuned/jetted just right.I live in Colorado 5000-10,000 elevation when riding so keep that in mind as well.
My current build
predator 212cc
rtc-6 cylinder head with 27mm intake 25mm exhaust valves
stock automotive style retainers
26lb valve springs with .060 shims on intake and exhaust sides
stock rods
stock rockers
billet rod +.020"
hemi flat top piston
.010" head gasket
ngk spark plug
billet flywheel 32 degree timing
black mamba senior camshaft
Mikuni 22mm with 115 main jet 15 pilot jet (38 keihin pilot)
header
Currently I have a 38 Keihin pilot jet that came pre-installed in my carb which I believe is equivalent to a 15 mikuni pilot??? Also running a 115 main. I attached the spark plug reading after WOT runs to this thread.
The engine currently only start & stays running with enrichment on. Which leads me to believe at least the pilot jet is lean. I have a 17.5 & 20 pilot on the way. Also have a #95 main #115 main #130 main #135 main.
Currently at 115 main 38 keihin pilot (Equivalent to mikuni 15 pilot???)
Going to try 130 main 17.5 pilot from mikuni
I had this mini bike up to 59.6 mph with more to go with this current main jet 115 mikuni large round head... so i know it is close however suspect it to be lean (suspect 125-130 main to be optimum)
Just wanted some suggestions regarding my spark plug color & what the ideal color should be for optimum jetting?
Down to the last leg of the project, and that’s getting my chikuni 22mm tuned/jetted just right.I live in Colorado 5000-10,000 elevation when riding so keep that in mind as well.
My current build
predator 212cc
rtc-6 cylinder head with 27mm intake 25mm exhaust valves
stock automotive style retainers
26lb valve springs with .060 shims on intake and exhaust sides
stock rods
stock rockers
billet rod +.020"
hemi flat top piston
.010" head gasket
ngk spark plug
billet flywheel 32 degree timing
black mamba senior camshaft
Mikuni 22mm with 115 main jet 15 pilot jet (38 keihin pilot)
header
Currently I have a 38 Keihin pilot jet that came pre-installed in my carb which I believe is equivalent to a 15 mikuni pilot??? Also running a 115 main. I attached the spark plug reading after WOT runs to this thread.
The engine currently only start & stays running with enrichment on. Which leads me to believe at least the pilot jet is lean. I have a 17.5 & 20 pilot on the way. Also have a #95 main #115 main #130 main #135 main.
Currently at 115 main 38 keihin pilot (Equivalent to mikuni 15 pilot???)
Going to try 130 main 17.5 pilot from mikuni
I had this mini bike up to 59.6 mph with more to go with this current main jet 115 mikuni large round head... so i know it is close however suspect it to be lean (suspect 125-130 main to be optimum)
Just wanted some suggestions regarding my spark plug color & what the ideal color should be for optimum jetting?
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