Got my bike running now after 8 months not being able to use it. During that time I was ok not riding it because i just rode my dirt bike. That covered. But then, my dirt bike got stolen and I had NOTHING to ride.
Anyway, bike is running the best I have had it running in in the 4 years I have had it. But like most things, detail matters. So I am just going back over my needle and main jet settings to see if there is a little more to be gained.
here is where I am at:
altitude 5200 ft.
muffler repacked
Unipods/ 4 -1 Yosh exhaust
just synched carbs
main jet 120
needle not yet shimmed
bike will start right up cold with full choke, no throttle.
bike starts right up hot, no throttle
to consider the main jet setting first, i was having lean surging at 117.5
increasing to 120 eliminated surging
I notice now though, I will get backfire/popping on deceleration after winding up engine in 2nd to 6-7000 rpm and shutting throttle off.
Is this telling me I am still a little lean on the main?
Follow this procedure:
http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html (http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html)
Anything less and you are chasing your tail...
Frank
allright, will do. thanx
Jetting is a function of throttle position rather than RPM.
The main jet is a factor at ~3/4 to WOT throttle. Less than that and you're mostly running on the idle circuit and slide needle. What idle jet are you running and what's the position of the needle?
float height is the answer....you are rich . lower the floats a smigen.
ok. I have got the bike to run really good, best it has. Blip test is good and just off idle running is good.
I am now just fine tuning the air screw position using quarter turn increments. is that a good amount of change for fine tuning idle and up to 2000 rpm?
next up, factorypro tech tuning instructions. idle jet is a 40, no washers on needle yet. air screw out 4 turns.
Quote from: bigbore2 on April 12, 2016, 04:01:00 PM
next up, factorypro tech tuning instructions.
?? Anything you do on jets or adjustments before you're through the Mains, Needles, Floats part of this procedure will likely need a redo... You should start with high RPM WOT and work through this procedure step by step. It will still take a couple of passes to get it all sorted, but at least you're going to be systematic in your approach and know exactly what you're adjusting and why.
Frank
I agree that is best. But for now, I just want to have a dependable ride with consistent running. and I seem to have that, finally.
It will be interesting when I do that how much change there will be.