Jetting Experts Apply Within
Posted April 23, 2002 - 04:53 PM
[ April 23, 2002: Message edited by: cowboyona426 ]
Posted April 23, 2002 - 05:02 PM
I would try a smaller pilot if fuel screw adjustments don't help. I made myself insane chasing a bog when all it turned out I needed a smaller pilot.
Posted April 23, 2002 - 05:06 PM
Originally posted by skthom2320:
A slight bog on the bottom probably means you need to lean out the pilot circuit but either turning IN the fuel screw, or putting a smaller pilot jet in.
I would try a smaller pilot if fuel screw adjustments don't help. I made myself insane chasing a bog when all it turned out was that I needed a smaller pilot.
Posted April 24, 2002 - 04:01 AM
Here is what I ended up with on my 00 after:
2: Blue Wire
3: Carb Clean
4: Beer Drinking
A: Pilot 45 - Turns out 1 3/4
B: Main 168 - Depends on alt, Temp and Weather may drop to 165, mainly 168
B: Needle = Cir clip 1 down from stock Note This raises the needle 1 notch
C: Bkmod / Duration is set for about .5 + - 1
Only issue I have is duirng the bike getting warm the damn things stops running at idle from time to time. This goes away once the bike is a operating temp.
Starts first kick every time, No Bog just pure adrenlin rush out of corners
Thump, Thump, Thump, Thump
Posted April 24, 2002 - 12:29 PM
Cowboy whats the altitude there where you ride? This can make a huge difference in settings.
Posted April 24, 2002 - 02:03 PM
P.S. Ego, maybe if you send me some of that beer stuff you were talking about, my bike will run as good as yours !
[ April 24, 2002: Message edited by: cowboyona426 ]
Posted April 24, 2002 - 02:23 PM
Stock jetting should be pretty close for you until it gets hotter and/or you go over 4 or 5 thousand feet, but IMO the jetting on the ’00 can be improved upon almost no matter where you ride it.
I’ll start with what I run in my ’00 and ’01 at 4k to almost 6k ft. of elev. where I normally ride, usually between 70 and 95 degrees F:
1 mm of pump stroke (IMO easier than trying to put a stop watch on it)
4th clip EJP needle (please try this $12 part, just ask for a stock ’01 needle)
200 MAJ (stock)
~85 Pilot Air Jet (stock is 100 and will result in a lean condition at higher rpms and low throttle i.e. popping on decel w/ a 40 pilot. You can get an adjustable PAJ from Sudco 800-998-3529, two parts, spring and screw, total $14).
1.5 turns out on fuel screw
Given the above I would suggest that you are probably okay w/ stock main. You definitely need to lose the stock needle, swapping for the stock ’01 needle is the best $12 mod you can make to a ’00 YZF, and you should try it in the 3rd and 4th clip from the top. Once you settle on that I think you should try a 40 pilot and see if it runs better at low rpms and low throttle settings. Once you have decided between the 42 and 40 pilot, with your bike fully warmed up, set your fuel screw to whatever setting gives you the best idle.
If you do end up with a 40 pilot jet you will probably want to order the adjustable
PAJ from Sudco (or Carb Parts Warehouse) and start at about 85 or 90 or maybe even try a WR PAJ if one is handy (a 75 vs. YZ’s 100), because with proper idle mix and a 40 pilot your bike will pop a bit on decel.
Hope this helps you out some.
BTW stock idle mix is 1.75 turns out (in is leaner, out richer).
Posted April 25, 2002 - 07:37 PM
[ April 25, 2002: Message edited by: Boit ]
Posted April 26, 2002 - 02:34 AM
One thing though, it's time to ditch the factory suggested settings and start doing it by feel. You have some baseline settings. Pick up a Kouba T-handle for that pilot screw adjustment. Not only is it a must for fine tuning the bike QUICKLY while it's running, but you can easily reach under and tweek it for altitude changes.
Also, you need to visually set that accelerator pump and time the squirt. When you have it off again make note of how much of a turn on the screw affects the pump duration, then when you need to fine tune and it's back together you'll know that a 1/8 turn will result in "X". 1/2 second is a good starting point.
PS- oil from the breather is normal.
[ April 26, 2002: Message edited by: Scott in KC ]
Posted April 26, 2002 - 12:52 PM
you should all be using the 160MAJ for more overrev as well as dropping the MJ 10 at the same time for more roll-on response.
Hick's 40PJ/85PAJ is close to my 40/75. check the PS setting by just doing little pop wheelies everywhere and adjusting the PS underneath.
the PS shouldn't be used to set the tickover, it should be used to help acceleration. having sorted that the needle straight will look after the idle and start-up of your machine.
like i said there or there abouts.
Posted April 26, 2002 - 01:00 PM
me thinks the web is bigger than we thought!
Posted April 26, 2002 - 04:28 PM
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