08-28-2009, 08:20 PM #1
Jetting expert needed..help please
I need help with a starting point for jetting. I am never good at a starting point.
So I figure that I better ask someone with more know-how than myself on where to start.
I will try and list all the mods, but I am sure I will forget some. If you need more info, please ask.
Fresh engine, only warm up time on it.
Ported to "Super Stock" specs by Greater Yamaha (some time ago)
.5mm overbore (coated pistons, Wiseco)
Crank trued, welded, balanced
Will be around 185 psi on pump (cutting back from 195)
Factory Mod Pipe
Dual 44 SBN on Riva manifold (ported) Primer no choke
K&N D-Shaped cones on velocity stacks
Boyeson CF reeds
Pre-mix 50:1 Yamalube
Plugs- NGK Palladium
Imp. - stock until I figure out what I need (help needed here too!)
I know I am forgetting a bunch, but maybe this is enough.
Not sure what jetting is in the 44s now, I can't read the damn small print and I REFUSE TO GET READING GLASSES!
Thanks all for your help
08-28-2009, 08:23 PM #2
Might copy this and post in the Yamaha Old School section.
08-28-2009, 08:24 PM #3
08-28-2009, 08:27 PM #4
Im not familiar with your setup on that motor,Oside might have an idea, hes good with carbs.
08-28-2009, 08:31 PM #5
Maybe he will catch one of these threads and have an idea.
All I know is when I was running my old engine with the Mod pipe, Factory's jetting specs were way lean. So lean the overheat sensor was shutting down the engine when I went WFO.
I figured the jetting out on that one and it ran like hell, but I don't want to go thru that again with thi$ engine.
08-28-2009, 09:31 PM #6
How many CC's is this and it would really help to know your previous jetting for starters.
08-28-2009, 10:20 PM #7
08-28-2009, 10:35 PM #8
If your running NON OEM 44's ...I ran the following on my old 93 61x/61x Blaster..and it was perfect
95 gram spring
08-28-2009, 10:43 PM #9
08-29-2009, 01:16 PM #10
I have been searching and I find combos "close" to mine, yet they are mostly the same, and the jetting is all over the place. Your looks to be "middle ground" so far.
Edit: Mike, you don't have the pilot and mains mixed up do you???
I would rather start rich and back it down, than the other way around.
Forgot to mention, most of my riding will be sea level. Some will be at 1500+- feet above. Want to get a Sea Level set up for now.
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