'05 AP Squirt Duration

12 replies to this topic
  • clark4131

Posted November 24, 2005 - 06:05 PM


My family abandoned me for Thanksgiving, so I figured I'd time my AP squirt to figure out where I'm at and why I'm still getting a bog. I video taped it and came up with .90 secs, +/- .05 seconds. It appears in the video that the squirt is just missing the slide so the timing with regard to the throttle plate seems to be spot on. It's in the mid 50's now at 4800' ASL, as far as temperature/elevation goes. My question now is, am I at the right duration for the squirt? I'm running a #40 leak, #45 Pilot, 170 Main, JD Blue #3, but I'm not sure whether the bog I have is lean or rich. Which way should I go, bigger or smaller on the leak? Since changing to the JD Blue, throttle response has gotten much better, but the bog remains. I put in a 48 Pilot, but had no adjustment on the fuel screw, so I went back to a 45, and I have no decel pop. Hmmm :applause: ...SC

  • rich1167

Posted November 24, 2005 - 06:15 PM


I am interested to see what other people may say. I have an almost identical situation. 45 to 55 deg, Elev 5500 feet. JD blue #3, air screw 1.5 turns 48 pilot 168 main 0 leak. The off idle bog has gotten much better with the changes from stock. Yet still remains. With the stock settings it would almost die in 1st and 2nd if you snapped the throttle. Now it just hesitates a bit. Should I be satisfied with this? I'm going to try a faster idle speed when I go out on Sat.

  • rich1167

Posted November 24, 2005 - 06:43 PM


I was just looking at the BK mod and at my bike. looks like this mod shortens up the squirt but won't do anything for timing. It looks like we could do something similar to what they do on the 400's and 426's. On the 05 450 it looks like we could use a smaller screw and tap it through the throttle cable cover. Has anywon done this? If so what were the results?

  • clark4131

Posted November 24, 2005 - 09:49 PM


I really got into this thing and did some full spectrum experimenting. Along with various jets, I also changed the AP diaphragm to see what the duration would be like with the various leak jets. Here's what I came up with...

Stock Diaphragm (5JG-14940-18-00)

-#0........... 1.07 seconds
-#35.......... .62 seconds
-#40.......... .54 seconds
-#45.......... .45 seconds
-#50.......... .36 seconds

Alternate Diaphragm (5JG-14940-17-00)

-#35.......... 1.06 seconds
-#40.......... .90 seconds
-#45.......... .73 seconds
-#50.......... .58 seconds

I didn't use the #0 on the Alternate Diaphragm because it would have been ridiculously long, somewhere in the neighborhood of 2.15 seconds. I finally settled on the #45 leak jet and the 3.1 Diaphragm as I was shooting for a duration between .7 and .8 seconds, based on the reading I've done from other threads and Thumper FAQ. There is a 42 leak jet available from Sudco which may be even more ideal, but I haven't decided what I'm going to do just yet. I haven't even tested the new jetting out yet in the dirt, but all this gives me an idea of what I can expect. All my timing was done via video camera and then calculated on a frame-by-frame examination. I hope you have as much fun with this as I did, but you won't get headache from all the gas fumes ...SC

  • ARin

Posted November 24, 2005 - 10:44 PM


clark, im in vegas too...and with a 45 pilot i was still getting pop on decel....but with the 48 pilot, i too dont feel like i have any adjustment with the fuel screw.

  • bomax

Posted November 24, 2005 - 11:44 PM


iam at sea level with a 06,35 degrees out today and 100% humid,i ran the blue on #3 and a 170,48 pilot.it studdered at steady speed just opening the trottle.

i went to the red needle on #4 with everthign else the same and it was alot better but a small studder in the same place.just cruising with throtlle barely open.

air screw at 1/75. any guesses?dont mean to hijack a thread its so damn cold out to try it all the time lol...

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  • bomax

Posted November 24, 2005 - 11:46 PM


also i dont get a bog at all with these settings.or with the 45 pilot,just alot of hunting under cruise mode.

  • clark4131

Posted November 25, 2005 - 06:13 AM


Arin, the fuel screw is a tricky thing. Don't even think of adjusting it until you've ridden the bike a good 20 minutes or so. It isn't warm enough to get any reaction until then. Also, an occasional decel pop is fine. If you have a loud, constant rapid-fire pop, that's a lean condition. Since Vegas is substantially lower than Reno, I would think a 48 would be perfect if you're not in the upper 80's and beyond temp-wise.

Bomax, the hunting you feel is normal. It's the TPS. Disconnect the connector and I'll bet dollars to donut holes it goes away...SC

  • SpeedBlitz

Posted November 25, 2005 - 06:18 AM


also i dont get a bog at all with these settings.or with the 45 pilot,just alot of hunting under cruise mode.

Disconnect your TPS and see if the studder goes away. If it does, the stutter is not jetting related.


  • rich1167

Posted November 25, 2005 - 02:51 PM


C.S. I read your post in the jetting forum and seen burned's response. I dropped to the 5th position on the JD blue and went for short test ride. No bog :applause:

  • clark4131

Posted November 25, 2005 - 04:11 PM


Thanks for being my guinea pig. What clip position were you at before?...SC

  • rich1167

Posted November 25, 2005 - 04:15 PM


Thanks for being my guinea pig. What clip position were you at before?...SC

I was at pos #3. My complete set up is in the 2nd post of this therad. I am running a real similar set up to you. My temps and elevation are real close too.

  • clark4131

Posted November 25, 2005 - 04:17 PM


Yah, I just went back and looked, duh! :applause: Thanks again...SC


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