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Author Topic: Trying to jet my Airstriker carb........  (Read 14260 times)

Offline Jimbo45

Trying to jet my Airstriker carb........
« on: January 30, 2015, 09:28:18 PM »
Hi folks!  First post here!  

A little background:  I had an R when I was 18, back in 1995-1996.  Loved it, but was sold when I was away at basic training.  Now, 20 years later, I came into another R, by chance, through a trade with a buddy.  It had been completely gone through about 8 years ago, frame powder coated, cases split powder coated, and complete rebuild, new plastics and A arms.  He rode it a few years, and after an airbox issue, he parked it for 3 years, and then I got it about a month and a half ago.

I went through it, cleaning, lubing, adjusting, and put a near new 69mm top end on it, and a new Keihin PWK 38 airstiker quad vent carb, and went through all the wiring and put in a good OEM coil.  

I have it running pretty well the past couple days finally.  Carlos from BDT had set up the carb with a # 165 MJ (included a 162 also) and a # 52 pilot (included a 50 also).  The DGH was set in the middle notch.  It was way rich at idle with the #52, and would only idle when cold, even with the airscrew like 4 turns out.  I went down to a #45 I had on hand, and at 2 turns out on the airscrew, it idles pretty well, but is still a bit rich, so I have a #42 coming that should put it in range.  

The quick spin I did the other day, the 165 MJ seemed a big boggy (but I didn't get to ride it much at all), so I put a 160 MJ in with the 45 PJ.  I rode it at speed, for the first time today.  It seems to run very strong at full throttle and maybe a bit soft through mid range throttle.  One thing I did notice, was after making a full throttle run through all gears, then slowing, downshifting, and turning around, when getting back on the gas, it seemed like it was bogging down, like it either was loading up, or the ignition was going flat.  I think it was fuel related bogging, since it did clear up after a few seconds on the gas, and since it had been running strong at full throttle.  When parking it, the cylinder wasn't overly hot, but pretty warm to the touch, and warmer than I would have guessed, since it was 34 degrees out, and I had putted it slowly, for about an eighth mile, to bring it back to the garage.  

So, I guess my plan is to maybe bump the MJ back up a notch to a 162 (the heat concerns me a little), and lower the needle, and do some more testing.  I know I need to do a plug chop, but I want to get it close by seat of the pants before doing that. Any thoughts on the bogging or power loss (it almost felt like I had left the gas valve off, and it was cutting out as I hit the gas) after slowing and downshifting from the open throttle run through the gears?  Needle too rich cause that?  I also have an inline fuel filter.... could that be restricting fuel fast enough that the bowl was to empty, until recovering?

Thanks for reading my thread, and I look forward to participating here.  By patient with me.....I have been on 4 strokes for YEARS, and this two stroke thing and jetting is taking a while to come back to me.  

« Last Edit: February 01, 2015, 03:20:10 PM by Jimbo45 »

Offline F-Red

Trying to jet my Airstriker carb........
« Reply #1 on: January 30, 2015, 09:49:48 PM »
Welcome here! Nice bike!
Want To See My Wieners?

Offline 2ndmoto

Trying to jet my Airstriker carb........
« Reply #2 on: January 31, 2015, 12:28:06 AM »
My suggestion. Tune in order.
1. Pilot
2. Needle
3. Main

If it bogs, that is typically lean. Sputters, typically rich. Definitely go back to the 52 pilot.  Good starter needles are ddj and dej. Start rich and work your way lean

Best regards
-Jason

Offline Jimbo45

Trying to jet my Airstriker carb........
« Reply #3 on: January 31, 2015, 01:12:54 AM »
Quote from: 2ndmoto;49601
My suggestion. Tune in order.
1. Pilot
2. Needle
3. Main

If it bogs, that is typically lean. Sputters, typically rich. Definitely go back to the 52 pilot.  Good starter needles are ddj and dej. Start rich and work your way lean

Best regards
-Jason
It won't even idle with the 52 pilot unless I crank the idle speed screw in all the way, and still barely.  It is pretty close , but still a bit rich, with the 45 pilot.
I read the jetting thread stickied at the top of the forum.  I have a good idea of what I need to do now, and how to tackle it.

Offline Tbone07

Trying to jet my Airstriker carb........
« Reply #4 on: January 31, 2015, 11:13:28 AM »
I know I had a DGH needle in all 3 of my motors and I seemed to have good luck with them
LED Performance 350R
Laegers-JD Performance-GThunder-HLS-PEP-HiPer-GBC

RIP Laz

Offline Jimbo45

Trying to jet my Airstriker carb........
« Reply #5 on: January 31, 2015, 11:24:01 AM »
Quote from: Tbone07;49609
I know I had a DGH needle in all 3 of my motors and I seemed to have good luck with them
I was told mine came with the DGH needle.  I need to take it out and see if its marked. I thought it had 3 clip grooves, but it does in fact have 5.

EDIT:  I was wrong, it does have the DGH needle with 5 clip grooves.  I had the needle I used in my boys 250EX rebuild, that had 3 grooves, the same night I was inspecting the new carb.  I was confused and thought it was the needle in my carb.
« Last Edit: February 01, 2015, 03:29:44 PM by Jimbo45 »

Offline Tbone07

Trying to jet my Airstriker carb........
« Reply #6 on: January 31, 2015, 11:33:00 AM »
Quote from: Jimbo45;49610
I was told mine came with the DGH needle.  I need to take it out and see if its marked.  Mine only has 3 clip positions instead of 5, is that normal?

I'm not sure if i've ever seen one with 3 clip positions. But i'm no jetting guru by any stretch of the imagination.

I don't know what the temp is in your neck of the woods, but it's 5 degrees here in Ohio, so don't forget that part of the equation. None of my bikes are jetted to idle well in this weather
LED Performance 350R
Laegers-JD Performance-GThunder-HLS-PEP-HiPer-GBC

RIP Laz

Offline Jimbo45

Trying to jet my Airstriker carb........
« Reply #7 on: January 31, 2015, 11:38:40 AM »
Quote from: Tbone07;49612
I'm not sure if i've ever seen one with 3 clip positions. But i'm no jetting guru by any stretch of the imagination.

I don't know what the temp is in your neck of the woods, but it's 5 degrees here in Ohio, so don't forget that part of the equation. None of my bikes are jetted to idle well in this weather
Yeah, it was 34 degrees yesterday.  I know it will run a bit leaner than it would in summer.

Offline Pumashine

Trying to jet my Airstriker carb........
« Reply #8 on: January 31, 2015, 11:54:48 AM »
Quote from: Jimbo45;49610
I was told mine came with the DGH needle.  I need to take it out and see if its marked.  Mine only has 3 clip positions instead of 5, is that normal?
Your carb was messed with by BDT. No the KEIHIN needle does not have 3 clip positions. They all have 5. What you were told can now be thrown out the window. Put in a DGH and start over.
Puma 408, Puma 431,  Pilot 412, Puma 431, Mini-tooth 486 Trx450r
89mm  Mini tooth Shearer in frame pipe chromed! With Cascade  Q

Offline F-Red

Trying to jet my Airstriker carb........
« Reply #9 on: January 31, 2015, 01:10:22 PM »
^^:distracted:
Want To See My Wieners?

Offline Pumashine

Trying to jet my Airstriker carb........
« Reply #10 on: January 31, 2015, 08:45:38 PM »
So Carlos is reading this thread and told the OP he would send a new DGH if it had only 3 grooves. :rofl:
Puma 408, Puma 431,  Pilot 412, Puma 431, Mini-tooth 486 Trx450r
89mm  Mini tooth Shearer in frame pipe chromed! With Cascade  Q

Offline fearlessfred

Trying to jet my Airstriker carb........
« Reply #11 on: January 31, 2015, 09:45:48 PM »
I like your bike and would suggest using bdts advise on there forum ,just for the sake of you getting what you paid for.Im not saying don't ask question here because that is welcome ,but as long as you are on friendly basis with carla,you will most likely get the right needle for your carb

Offline fearlessfred

Trying to jet my Airstriker carb........
« Reply #12 on: January 31, 2015, 09:57:56 PM »
Quote from: Jimbo45;49602
It won't even idle with the 52 pilot unless I crank the idle speed screw in all the way, and still barely.  It is pretty close , but still a bit rich, with the 45 pilot.
I read the jetting thread stickied at the top of the forum.  I have a good idea of what I need to do now, and how to tackle it.
If you having to turn air screw in to get to idle ,that would suggest you are to lean on pilot, opening the aircrew allows more air to be mixed with fuel.So if slow jet is to rich you would need to open aircrew to lean out


Offline Jimbo45

Trying to jet my Airstriker carb........
« Reply #14 on: January 31, 2015, 11:23:47 PM »
Quote from: fearlessfred;49652
If you having to turn air screw in to get to idle ,that would suggest you are to lean on pilot, opening the aircrew allows more air to be mixed with fuel.So if slow jet is to rich you would need to open aircrew to lean out
No, I had to turn in the IDLE SPEED SCREW (or slide stop screw), all the way until the spring was compressed, to get it to idle with the 52 pilot....NOT the airscrew.  With the 52 pilot, I could back the air screw all the way out and it would still be rich.

 

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