I too live in Can, I highly recommend ordering carb parts via sudco.com They have good prices, everything in stock, and ship via USPS. I order two CCK needles from them (@ $5.51 ea, cheap), spare needle clips, carb screws and a standard choke. Everything was delivered to my door within 5 days. I think they're based in California
2011 ASII 36 Jetting - what were they thinking?
- Thread starter Neil E.
- Start date
I suspect that the AS II might need a bigger shank diameter to make the idle circuit function better.
Didn't know they were still around; last time I was there was in 1970 when I bought some Klotz oil. I'll have to look them up.
Digging into things a bit deeper with a compression test (throttle held wide open, cold engine):
1st kick 95 psi
2nd kick 130 psi
3rd kick 150 psi
4th kick 165 psi
5th kick 180 psi
6th kick 185 psi
7th kick 190 psi
8th kick 195 psi
9th kick 200 psi
10th kick 200 psi
The tester dial is 3.750" in diameter and the hose is 21" long. I expect it took multiple kicks because of the hose volume. (I bought it for testing a 62 Chev with a 327; before that I had a hand push unit that was fine for flat head engines).
The investigation continues with a squish test. The measurement I came up with was .0615" (1.56mm). I had acid core solder that was .110" diameter and did a single pass instead of rocking the crank back and forth. This was good enough for testing purposes. I would do a "head off" measurement for machining purposes.
Next is the powervalve check. I removed the starter motor and powervalve cover. By grabbing the threaded stub on the PV shaft I get about 1/16 movement across the engine. This just proves the valve is free. I can rotate the shaft CCW about 4 to 5 degrees before feeling any resistance. When I release the shaft it feebly moves back CW. Extra force CW moves it only the slightest perceptible amount, so I think the PV is closing.
The real question is whether it's closing good enough. The tiny bit of preload is so slight the valve may not be closed when the engine is running.
1st kick 95 psi
2nd kick 130 psi
3rd kick 150 psi
4th kick 165 psi
5th kick 180 psi
6th kick 185 psi
7th kick 190 psi
8th kick 195 psi
9th kick 200 psi
10th kick 200 psi
The tester dial is 3.750" in diameter and the hose is 21" long. I expect it took multiple kicks because of the hose volume. (I bought it for testing a 62 Chev with a 327; before that I had a hand push unit that was fine for flat head engines).
The investigation continues with a squish test. The measurement I came up with was .0615" (1.56mm). I had acid core solder that was .110" diameter and did a single pass instead of rocking the crank back and forth. This was good enough for testing purposes. I would do a "head off" measurement for machining purposes.
Next is the powervalve check. I removed the starter motor and powervalve cover. By grabbing the threaded stub on the PV shaft I get about 1/16 movement across the engine. This just proves the valve is free. I can rotate the shaft CCW about 4 to 5 degrees before feeling any resistance. When I release the shaft it feebly moves back CW. Extra force CW moves it only the slightest perceptible amount, so I think the PV is closing.
The real question is whether it's closing good enough. The tiny bit of preload is so slight the valve may not be closed when the engine is running.
stainlesscycle
Site Sponsor
you can also put the pipe back on with the left pv cover open, and watch it open when running - that will tell you if it's opening and closing all the way..
My PV inspection has been done via the left cover only. I cleaned the PV stub shaft and drew a vertical line on it. When the motor is running, the PV is jiggling in that small play I mentioned before. There is no real force holding it closed; but it does appear to be closed. The revs have to be increased noticeably before it will open. When it opens, the operation looks to be proportional to RPM.
Should the PV be able to jiggle slightly at idle or should it be firmly closed? It looks "adequate" to me. I was expecting to find some mechanical reason that would explain the poor carburation, but everything seems OK.
I'll post up what I find after some jetting changes. It may be a while before I have time for more experimentation.
Should the PV be able to jiggle slightly at idle or should it be firmly closed? It looks "adequate" to me. I was expecting to find some mechanical reason that would explain the poor carburation, but everything seems OK.
I'll post up what I find after some jetting changes. It may be a while before I have time for more experimentation.
stainlesscycle
Site Sponsor
oops - i meat the right cover. never tried running it with left cover open...
CACTUSREID
New member
mrkartoom, have you tried a leaner slide? myself.i"ve found that you can chase your tail forever,trying to balance pilots .needles air screws and of course the dreaded over tightened idle screw problem. change out your slide for at least 1 or 2 numbers higher than what is currently marked on it, and then sort out your jets from there. i have yet to see a gasser that has not been easier to jet and to get it to idle,when a leaner slide was installed.
motogroove
New member
I just purchased a compression tester myself.
From the directions:
"On a normal cylinder, the gauge needle should travel up-scale on each compression stroke until it reaches a peak value."
So, it is normal for it to take multple kicks.
None of the below matters if you are happy with your test numbers, but:
My directions say to do the test on a warm engine. I wonder how much difference that makes.
It also says to remove the air filter.
Thoughts on testing cold? That would certainly be less hassle.
mrkartoom
New member
I put a #8 slide on order last week and hope to see that sometime soon. I figured it was worth a try after not having much luck so far. Thanks I'll report back when I get some results.
GMP
Active member
I've been saying this from the beginning and I agree 100%. Especially with the 300s, and probably even more so with the 36mm carb. A 36 will have a very strong signature on a 300.
mrkartoom
New member
I'm one of these people that don't listen and have to learn the hard way.
Anyhoo mine has the 38mm throat so hopefully this will indeed help.
One of the things that has me curious about my carb (AS 2) is why it has no low pressure tower above the needle jet. I've seen skoodles of AS pics and they have. Anyone know why it doesn't have one?
My directions say to do the test on a warm engine. I wonder how much difference that makes. It also says to remove the air filter. Thoughts on testing cold? That would certainly be less hassle.
I doubt the foam filter will make a difference. Testing a warm engine makes sense if you are trying to get the best accuracy. On a multi-cylinder engine, the difference between cylinders is usually more important than the actual reading.
The purpose of my testing was to see that things are reasonable. You could test both ways and let us know if you find a difference.
Fred1956
New member
None of the below matters if you are happy with your test numbers, but:
My directions say to do the test on a warm engine. I wonder how much difference that makes.
It also says to remove the air filter.
Thoughts on testing cold? That would certainly be less hassle.
IMO as far as the air filter goes it should be a moot point, Way more important to hold throttle at WOT..
When I installed the JD kit, I found why my bike seemed so grossly rich. The N1EF needle had the clip in the middle groove!
I set it up close to the JD recommendations. 38 pilot, 1.5T, red needle #4, but with a 175 main instead of a 170.
The large section of the stock needle measures .1065" diameter. JD's blue is a hair smaller at .1060" diameter. The JD red measures .1075" and provides the leanest idle condition.
With the 38 pilot I could get a passable idle at 1T on the air screw. Past 1.25T it was erratic. I changed to the 40 pilot and got an idle at 1.5T out. Past 1.75T it gets erratic.
Far better operation than before, but I can only tell so much going up and down the parking lot. The tachometer in the Trailtech Voyager indicates the idle is somewhere in the 2400 to 2500 RPM range. What should a typical idle speed be?
I set it up close to the JD recommendations. 38 pilot, 1.5T, red needle #4, but with a 175 main instead of a 170.
The large section of the stock needle measures .1065" diameter. JD's blue is a hair smaller at .1060" diameter. The JD red measures .1075" and provides the leanest idle condition.
With the 38 pilot I could get a passable idle at 1T on the air screw. Past 1.25T it was erratic. I changed to the 40 pilot and got an idle at 1.5T out. Past 1.75T it gets erratic.
Far better operation than before, but I can only tell so much going up and down the parking lot. The tachometer in the Trailtech Voyager indicates the idle is somewhere in the 2400 to 2500 RPM range. What should a typical idle speed be?
Jakobi
Super Moderator
And for those who aren't using JDs needles.. This falls in line with everything thats been said before..
Diamter of needles.
JD Blue ~ E (N1EE, N3EE, NOZE)
JD Red ~ W/I (N1EI, NOZI, N3EW)
The nozzle jet shroud has a fairly large notch in it. There has been some discussion about the value of the notch.
It feels like I am getting some pull-over from the needle since the slide has to be raised to get an idle.
Should the air screw be providing all the air needed for idle if the jetting is correct? The higher the slide the poorer the quality of idle. Does a leaner slide pass more air at idle or does it only reduce the "signature" off idle?
It feels like I am getting some pull-over from the needle since the slide has to be raised to get an idle.
Should the air screw be providing all the air needed for idle if the jetting is correct? The higher the slide the poorer the quality of idle. Does a leaner slide pass more air at idle or does it only reduce the "signature" off idle?
