Author Topic: Idle set screw all the way in to maintain idle  (Read 3910 times)

Offline jksymz75

  • Hatchling
  • **
  • Posts: 139
Idle set screw all the way in to maintain idle
« on: July 06, 2016, 07:29:25 PM »
I upgraded to pods on my LMIII and now I need to screw the LH Idle set screw all the way in just to maintain a regular idle. Do I need to jump up to a higher idle jet (currently 50)?

Also, if you feel I should jump to a higher main jet or a different needle, all experience is welcome.

I searched the board but couldn't find this answer so any help is appreciated.

My current settings:

atomizer: 262
needle: k27 (2nd groove)
main jet: 120
idle jet: 50
slide: 50/3
choke jet: 75

'83 LM III
'93 Ducati 900ss
'21 Honda CRF300L Rally

Offline Muzz

  • Gaggle Hero
  • *****
  • Posts: 7055
  • On the backside of the planet.
  • Location: Christchurch, New Zealand
Re: Idle set screw all the way in to maintain idle
« Reply #1 on: July 06, 2016, 07:37:00 PM »
My first thought would be that your level is out.
Muzz. Cristchurch, New Zealand
03 Breva

Life is just a bowl of Allbran
Ya wake up in the morning and it's there

Offline guzzisteve

  • Gaggle Hero
  • *****
  • *
  • Posts: 11424
  • "Just Ride It"
Re: Idle set screw all the way in to maintain idle
« Reply #2 on: July 06, 2016, 07:51:53 PM »
I would make sure the pod is not shedding oil, by using the sticky stuff.
"Pray through Carlo & your bike shall be healed"
Location: Planet Earth

redrider

  • Guest
Re: Idle set screw all the way in to maintain idle
« Reply #3 on: July 06, 2016, 08:00:17 PM »
Guzziology recommends the following:

K18 needle 3rd groove, 60/3 slide, Idle jet 50(ok there), 268 atomizer type AB(3793 5506).

There is no listing for the main jet in Guzziology that I can find at the moment. Your slide can be modified by enlarging the cutaway from 5mm(50/x) to 6mm(60/x) height. The x denotes the accelerator pump ramp angle. Some have deleted the pumps with no ill effects. If you run out of steam on top end, try upping the main by 10%.

After porting, polishing, pods and Lafranconi's, the Mille responded well to the 10% rule for the mains. That bike is on Youtube-89Millegt channel. Idle screws should be the same or nearly so. You have something amiss-perhaps the accelerator pump arm out of position? Just sayin' from prior experience.

Wildguzzi.com

Re: Idle set screw all the way in to maintain idle
« Reply #3 on: July 06, 2016, 08:00:17 PM »

Offline pressureangle

  • Gaggle Mentor
  • ****
  • *
  • *
  • *
  • *
  • *
  • Posts: 972
  • '97 1100 Sport i, '89 Mille GT
Re: Idle set screw all the way in to maintain idle
« Reply #4 on: July 06, 2016, 08:11:43 PM »
What else did you do? Since the airflow is tiny at idle, the restriction of a stock airbox vs. pods or opens is insignificant. Sounds more like a blockage/supply problem to me.

Did you have the carbs or bowls off? How old are your fuel hoses? Old hose can be deteriorated by the ethanol in gasoline and comes out in tiny dust particles that can gum up in a ball, or flakes big enough to plug the idle jet/passage even while small enough to pass through the main jet.
Something wistful and amusing, yet poignant.

pete roper

  • Guest
Re: Idle set screw all the way in to maintain idle
« Reply #5 on: July 06, 2016, 08:31:55 PM »
If shrouded 'Lean Burn' type carbs.

Pilot 50
50 slide
268 Atomiser
K18 needle, second or third notch
120 main

Sounds to me like either the chokes aren't seating or the pilot mis is maladjusted.

Online Chuck in Indiana

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • Posts: 29445
Re: Idle set screw all the way in to maintain idle
« Reply #6 on: July 06, 2016, 09:25:08 PM »
Choke not seating. Pete beat me to it.
Oh.. forgot my mantra.. carburation problems are generally ignition. Bad coil, plug wire or plug.  :smiley: :boozing:
Chuck in (Elwood) Indiana/sometimes SoCal
 
87 AeroLario
95 Skorpion tour
22 Royal Enfield Classic 3 fiddy
 "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."
Albert Einstein

Offline Rich A

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • Posts: 3151
Re: Idle set screw all the way in to maintain idle
« Reply #7 on: July 06, 2016, 09:45:09 PM »
You didn't change your elevation, did you?

Rich

Offline kevdog3019

  • Gaggle Hero
  • *****
  • Posts: 5648
Re: Idle set screw all the way in to maintain idle
« Reply #8 on: July 06, 2016, 10:11:41 PM »
If your set screw is all the way in now just to make it idle fine then it's not electrical. That would have no affect on electrical one way or the other and you made it better (so you say). You can't make a coil better by a carb set screw. I'd look at your idle jet or crap in the lines/carb internals as someone else suggested. My experience with pods has been minimal change with carbs.
'86 V65 "Super" Lario
'85 Honda Nighthawk 700s
'86 V65 Lario

Offline SED

  • Gaggle Hero
  • *****
  • *
  • *
  • Posts: 1627
Re: Idle set screw all the way in to maintain idle
« Reply #9 on: July 06, 2016, 11:00:05 PM »
Jammed float or dirt under the needle on the left hand side?  I've had a small piece of gasket get stuck in there.

It looks like you have the jetting Guzziology says is for USA LMIII except for the main jet, idle jet and choke jet.

USA (Guzziology)
idle 53 (Europe is 50)
main 120 (Europe is 115)
needle K27 2nd notch down
needle jet 262
slide 50/3
choke 70 (mine had 75 jets when I got it)

My guess is that you have a stuck float/dirt under the needle valve on the left.



1983 LeMans III
1981 Monza
1947 Ariel Red Hunter
1939 Ariel Red Hunter
1937 Guzzi GTV

Offline jksymz75

  • Hatchling
  • **
  • Posts: 139
Re: Idle set screw all the way in to maintain idle
« Reply #10 on: July 06, 2016, 11:05:57 PM »
wow, sat down and watched a movie and came back to all this great advice. I'm going to pull off the carbs and make sure they're clean, that the chokes are seating properly, and that the float levels are correct and that no debris is floating around in there that could be getting in the way of flow. I guess I overestimated the effect pods would have, although this did seem to happen when I installed the pods.
'83 LM III
'93 Ducati 900ss
'21 Honda CRF300L Rally

Offline SED

  • Gaggle Hero
  • *****
  • *
  • *
  • Posts: 1627
Re: Idle set screw all the way in to maintain idle
« Reply #11 on: July 07, 2016, 12:14:03 AM »
Ack! Choke not seating!   :thumb:   Didn't register 'til I read it again.  Any chance one of the choke cables got pulled out of its stop socket?  If so it will hold the choke open on that side.  Easy to do on the left by just pushing it aside to install the left pod because on that side it seats on the outside of the carb. 
1983 LeMans III
1981 Monza
1947 Ariel Red Hunter
1939 Ariel Red Hunter
1937 Guzzi GTV

Online Chuck in Indiana

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • Posts: 29445
Re: Idle set screw all the way in to maintain idle
« Reply #12 on: July 07, 2016, 09:49:46 AM »
Ack! Choke not seating!   :thumb:   Didn't register 'til I read it again.  Any chance one of the choke cables got pulled out of its stop socket?  If so it will hold the choke open on that side.  Easy to do on the left by just pushing it aside to install the left pod because on that side it seats on the outside of the carb.

Most likely candidate for the win..
Chuck in (Elwood) Indiana/sometimes SoCal
 
87 AeroLario
95 Skorpion tour
22 Royal Enfield Classic 3 fiddy
 "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."
Albert Einstein

Offline Two Checks

  • Gaggle Hero
  • *****
  • Posts: 6035
Re: Idle set screw all the way in to maintain idle
« Reply #13 on: July 07, 2016, 10:19:00 AM »
Check the o ring on the pilot jet screw first. Might save some work.
1990 Cal III f/f  "Il Duce' III"
1987 1000 SPII "Il Duce' II"

Offline jksymz75

  • Hatchling
  • **
  • Posts: 139
Re: Idle set screw all the way in to maintain idle
« Reply #14 on: July 14, 2016, 06:23:06 PM »
 finally have a minute to get in the garage.

checked o-ring on idle adjust and air/fuel adjust screws and they both seemed a little tired so I replaced them.

cleaned out the screen from fuel hose inlet and there where some fine particles trapped there so not sure if finer particles made their way through.

checked the floats and, if I'm reading this correctly, they are at 25mm(!). manual says between 17.5-18.5. so (a) did I read them correctly in the pics attached and (b) what is the method to bend the tab to get them to the proper height?





'83 LM III
'93 Ducati 900ss
'21 Honda CRF300L Rally

Offline flangeman_70

  • Gosling
  • ***
  • Posts: 289
Re: Idle set screw all the way in to maintain idle
« Reply #15 on: July 15, 2016, 04:54:11 AM »
finally have a minute to get in the garage.

checked o-ring on idle adjust and air/fuel adjust screws and they both seemed a little tired so I replaced them.

cleaned out the screen from fuel hose inlet and there where some fine particles trapped there so not sure if finer particles made their way through.

checked the floats and, if I'm reading this correctly, they are at 25mm(!). manual says between 17.5-18.5. so (a) did I read them correctly in the pics attached and (b) what is the method to bend the tab to get them to the proper height?







You need to stand the carb on its head to measure the float height. From what I can see here it is laying down and you can't measure it accurately in that orientation.

Good luck.

Adam
You only went to school to learn how to learn

Adam

SP III 1990
V10 Centauro 1996

redrider

  • Guest
Re: Idle set screw all the way in to maintain idle
« Reply #16 on: July 15, 2016, 06:45:44 AM »
At 25mm, the floats are not your problem. If anything, the bike would fuel starve at high rpm. Laying the carb the manifold side of the venturi allows the float needle to seat without compressing the over-travel plunger in the center if it has one. If not, invert the body completely. MY 2c.

LaMojo

  • Guest
Re: Idle set screw all the way in to maintain idle
« Reply #17 on: July 15, 2016, 06:59:57 AM »
Idle circuit within the carb may be partially restricted.  Make sure the orifice in the jet is completely open.

Offline jksymz75

  • Hatchling
  • **
  • Posts: 139
Re: Idle set screw all the way in to maintain idle
« Reply #18 on: July 15, 2016, 07:18:06 AM »
my floats are connected so I measured them according to the method laid out in the Dell'orto manual (and also thisoldtractor.com) by lying the carb on its side, not its top.

did I get that wrong?



'83 LM III
'93 Ducati 900ss
'21 Honda CRF300L Rally

Offline Muzz

  • Gaggle Hero
  • *****
  • Posts: 7055
  • On the backside of the planet.
  • Location: Christchurch, New Zealand
Re: Idle set screw all the way in to maintain idle
« Reply #19 on: July 15, 2016, 09:59:26 PM »
my floats are connected so I measured them according to the method laid out in the Dell'orto manual (and also thisoldtractor.com) by lying the carb on its side, not its top.

did I get that wrong?





Don't know about the Dell'orto carbs but every carb on every bike I have owned measured the level with the carb upside down so the weight of the float is supported by the needle in the seat, and then measured from the body base to the top of the float.

Anyone, is the Dell'orto different?
Muzz. Cristchurch, New Zealand
03 Breva

Life is just a bowl of Allbran
Ya wake up in the morning and it's there

Offline SED

  • Gaggle Hero
  • *****
  • *
  • *
  • Posts: 1627
Re: Idle set screw all the way in to maintain idle
« Reply #20 on: July 16, 2016, 12:50:12 AM »
my floats are connected so I measured them according to the method laid out in the Dell'orto manual (and also thisoldtractor.com) by lying the carb on its side, not its top.

did I get that wrong?





That's the way I measure mine (vertical float arm), but, after looking at a lot of floats, I think the 18mm float height is wrong if you are running newer floats and the spring loaded needles.

Don't mess with your float level.  Check the other things (choke plunger) first - Certainly if the problem is only on one side.  My floats measure about 25mm with no compression of the spring-loaded plunger and about 20mm with a vertical float arm.

I have new spring loaded needles.  I bought new white plastic floats (not adjustable) and they measure 20-21mm and they are lighter (they close the needle at a lower fuel level for the same measurement) than the black plastic floats.   I've tried brand new black plastic floats and they measure about 20mm or so on their OD.  I can make the black plastic floats give an 18mm measure, but the new float arms need to be bent A LOT and then the needle only seats at nearly full upward travel (where it bangs into the chamber roof).  The bent float arm looks wrong and the bike doesn't run as well. 

The source of the 18mm measure may be the design of the original PHF brown plastic floats.  They have a chamber with a raised seam around it.  They measured about 20mm on their OD, but if you ignore the raised seam and measure the outside of the chamber they measure 18mm without bending the crap out of the arm.
1983 LeMans III
1981 Monza
1947 Ariel Red Hunter
1939 Ariel Red Hunter
1937 Guzzi GTV

Offline jksymz75

  • Hatchling
  • **
  • Posts: 139
Re: Idle set screw all the way in to maintain idle
« Reply #21 on: July 18, 2016, 10:01:48 AM »
That's the way I measure mine (vertical float arm), but, after looking at a lot of floats, I think the 18mm float height is wrong if you are running newer floats and the spring loaded needles.

Don't mess with your float level.  Check the other things (choke plunger) first - Certainly if the problem is only on one side.  My floats measure about 25mm with no compression of the spring-loaded plunger and about 20mm with a vertical float arm.

I have new spring loaded needles.  I bought new white plastic floats (not adjustable) and they measure 20-21mm and they are lighter (they close the needle at a lower fuel level for the same measurement) than the black plastic floats.   I've tried brand new black plastic floats and they measure about 20mm or so on their OD.  I can make the black plastic floats give an 18mm measure, but the new float arms need to be bent A LOT and then the needle only seats at nearly full upward travel (where it bangs into the chamber roof).  The bent float arm looks wrong and the bike doesn't run as well. 

The source of the 18mm measure may be the design of the original PHF brown plastic floats.  They have a chamber with a raised seam around it.  They measured about 20mm on their OD, but if you ignore the raised seam and measure the outside of the chamber they measure 18mm without bending the crap out of the arm.

thank you, this is great insight. I'm thinking my problem came from the worn out o-ring in the idle adjustment screw. hope to get a chance to get back in the garage soon and put things back together and see if that does the trick.
'83 LM III
'93 Ducati 900ss
'21 Honda CRF300L Rally

Offline jksymz75

  • Hatchling
  • **
  • Posts: 139
Re: Idle set screw all the way in to maintain idle
« Reply #22 on: July 19, 2016, 07:05:41 AM »
Check the o ring on the pilot jet screw first. Might save some work.

This was the culprit. Changed out the o-rings and the bike starts, runs and idles better than ever. Great info, thanks!
'83 LM III
'93 Ducati 900ss
'21 Honda CRF300L Rally

Offline SED

  • Gaggle Hero
  • *****
  • *
  • *
  • Posts: 1627
Re: Idle set screw all the way in to maintain idle
« Reply #23 on: July 19, 2016, 09:51:05 AM »
This was the culprit. Changed out the o-rings and the bike starts, runs and idles better than ever. Great info, thanks!

Great to hear!
1983 LeMans III
1981 Monza
1947 Ariel Red Hunter
1939 Ariel Red Hunter
1937 Guzzi GTV

Offline Two Checks

  • Gaggle Hero
  • *****
  • Posts: 6035
Re: Idle set screw all the way in to maintain idle
« Reply #24 on: July 19, 2016, 04:13:26 PM »
WOOT!
1990 Cal III f/f  "Il Duce' III"
1987 1000 SPII "Il Duce' II"

 

***Wildguzzi Official Logo High Quality 5 Color Window Decals Back In Stock***
Shipping in USA Only. Awesome quality. Back by popular demand. All proceeds go back into the forum.
http://www.wildguzzi.com/Products/products.htm
Advertise Here