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Pan-Shovel-head51-79
18th February 2012, 12:37
Anthony14

Looking from the air cleaner side of a mounted carb. The one on the right is (fast idle adjusting) This adjustment is done by pulling the choke to #2 step setting, Turning screw to 1500 rpm. Note #1 on choke is all the way in.

The screw on left is (Throttle stop screw) adjust to 900-950 rpm


What is step 2?


Hey guys
I have this carburetor on my bike, to throw cold start choke and idle is 1000 rpm, according to the manual should be 1500, how should I adjust the idle speed fast?
I have a main jet of 180 and a low of 68.
I would like to explain to me the complete adjustment procedure for this model carburetor, what do I do first, adjusting the mix, should I wait to take working temperature spark plugs godark. I have the Haynes manual but I do not understand many things,
I hope I can express myself well and understand what I ask.
Thanks in advance
http://i1152.photobucket.com/albums/p485/Pan-Shovel-head51-79/P2130006.jpg

IronMick
18th February 2012, 13:15
Step 2:

The choke has 4 positions; if pulled out gently it stops at each position; ...

choke knob all the way in
choke out a little, maybe 1/2"; choke plate is still fully open but the "fast idle cam" moves the throttle valve to the fast idle position; this is step 2
pull choke out a little more and plate is half open and valve opens a little more
choke all the way out, plate is fully closed and valve is in the highest idle position


With the engine fully warmed up gently pull out the choke know to position #2, then adjust the idle speed [not the idle mixture] to 1500 RPM.

If the other settings are good then the idle should settle down to 1000 RPM when you push the choke knob back in.

Please see this Sticky thread for setting the pilot/mixture screw ...

Setting The Pilot Screw on Your IronHead
http://xlforum.net/vbportal/forums/showthread.php?t=71361

You can either set the mixture first or set the fast idle first, then do the other. Then you probably must re-do which ever you did first.

IronMick
18th February 2012, 13:26
Hey Guys, this man has this carb on a ShovelHead. Does anyone here know of a good ShovelHead forum?

Pan-Shovel-head51-79
18th February 2012, 14:32
http://i1152.photobucket.com/albums/p485/Pan-Shovel-head51-79/_keihin_carb_78-80_1.jpg

IronMick Hello, could give me a dissertation full adjustment model Keihin please step by step

IronMick
18th February 2012, 14:53
... could give me a dissertation full adjustment model Keihin please step by step

I'll be back later today or tonight to answer this.

Pan-Shovel-head51-79
18th February 2012, 15:01
I hope to go to garage and do

steve-o-
18th February 2012, 15:23
Try "shovelhead.us". Great shovel forum.

JBGoode
18th February 2012, 16:05
I've never used my choke on my bike, I just give it three twists and it usually starts right up, to warm it up, I just twist it til it's at a decent speed to warm it up and hold it for a minute or so... I'm sure my neighbors love it. :D

Pan-Shovel-head51-79
18th February 2012, 16:27
will wait to go to garage and do

nikki
18th February 2012, 16:47
I've never used my choke on my bike, I just give it three twists and it usually starts right up, to warm it up, I just twist it til it's at a decent speed to warm it up and hold it for a minute or so... I'm sure my neighbors love it. :DJB I use your way of starting the bike but the OP needs to adjust his carb so all he need to start his bike like you and I do .Nikki

IronMick
18th February 2012, 18:00
The carb that the OP has was used from 1979-on. Previous year carbs did not have the fast idle adjustment. It is important that this adjustmnent be done correctly. The basics are in my post #2 above.

First follow the procedure in the Sticky i quoted to set the pilot/mixture screw; then set the fast idle as outlined above; then review the mixture screw setting.

Pan-Shovel-head51-79
22nd February 2012, 18:04
Hi guys.
The adjustment of the mix, I understand, the idle adjustment also, do not understand is the fast idle speed, if I do a hot engine, the choke must be off and then turn the fast idle screw until it arrives at 1500 rpm or with engine warm and the choke in the second position, turn the screw until it reaches 1500 rpm. and then back to adjust the idle, or when you reach 1500 rpm I have completed the setup.

Sorry to be awkward, there is little information and I find I'm not out of the doubt

IronMick
22nd February 2012, 18:29
... do not understand is the fast idle speed, if I do a hot engine, ... the choke in the second position, turn the screw until it reaches 1500 rpm ...

This is correct. This is what the factory manual says to do.

I do not recall if i had to re-do any of the other adjustments after doing this one. I think not.

Mick

Pan-Shovel-head51-79
22nd February 2012, 19:33
there is an image out there where you can see the four positions of the butterfly valve?

IronMick
23rd February 2012, 03:21
there is an image out there where you can see the four positions of the butterfly valve?

I have one of these carbs for spare parts so i just made these pic's. There are three areas to watch closely as you slowly pull out the choke knob on your carb. I have circled these in red in the first pic. Two small and one large. Note that the large area is connected to the throttle so when it moves even a very small amount the throttle opens a little and the idle speed increases.

It is the position of these three parts that is important in this sequence, not the position of the choke plate. What is important is how these movements affect the throttle opening, and therefore the idle speed ...

Choke position #1 ...

http://i486.photobucket.com/albums/rr227/mdawdy/1980Parts/Choke1A.jpg

Choke position #2 ...

http://i486.photobucket.com/albums/rr227/mdawdy/1980Parts/Choke2.jpg

Choke position #3 ...

http://i486.photobucket.com/albums/rr227/mdawdy/1980Parts/Choke3.jpg

Choke position #4 ...

http://i486.photobucket.com/albums/rr227/mdawdy/1980Parts/Choke4.jpg

From the manual ...

When the choke knob is pulled out to the second position, the choke plate is still fully open, but the fast idle cam moves the throttle valve to the fast idle position.

Note that in my pics the choke plate has moved for position #2, which accordiung to my manual it is not supposed to. My manual is a Sportster manual and this is a ShovelHead carb so that may be why; or this carb may not be correctly set up.

Pan-Shovel-head51-79
23rd February 2012, 14:00
Thank you very much Mick, I do understand, then in that position 2, with the screwdriver turn the fast idle screw, moving the cam and increasing the speed to 1500 (with engine warm), so that when starting in cold ... ,

IronMick
23rd February 2012, 16:17
Yes! and you are most welcome.

83XLX
23rd February 2012, 16:42
Nice descriptive pics, Mick.

Pan-Shovel-head51-79
25th February 2012, 00:31
Hi guys.
Something is not right, I'm doing all the settings and the bike does not go round, I can not hear the pistonazos (pocoton - pocoton) a data, and is that I have exhaust free. What should I look?

IronMick
25th February 2012, 00:53
bike does not go round - Engine does not turn over at all? Do you get spark at the plugs?

I understand that pistonazos are pistons. I do not understand pocoton.

I do not understand your use of the word data, or what you mean by I have exhaust free.

Please try again to explain.

Pan-Shovel-head51-79
25th February 2012, 09:40
Sorry, I'm helping with the Google translator, the best I can ...
the bike starts, the problem is that the idle at 900-950rpm seems high, and I can not fit a harmonious sound, and I commented that I have mounted exhaust pipes free, I can not match the sounds of the exhaust pipes .
will try to make a video

IronMick
25th February 2012, 13:11
Yes, pictures or a video would help.

I will do the best i can here. You might also try this ...

Español
Esta área del forum está para la lengua española. You will be redirected to Sportster.cc which is run by XL Forum member Predator
http://xlforum.net/vbportal/forums/forumdisplay.php?f=48

Pan-Shovel-head51-79
19th March 2012, 18:59
http://http://s1152.photobucket.com/albums/p485/Pan-Shovel-head51-79/?action=view&current=190312.mp4

Hey guys, have if this video can explain some, if not, I will make another. regards

Pan-Shovel-head51-79
19th March 2012, 19:04
190312.mp4 video by Pan-Shovel-head51-79 - Photobucket

IronMick
20th March 2012, 03:01
Hey guys, listen to this video especially if you are a little familiar with ShovelHeads. It sounds OK to me except that maybe the idle speed is a bit low. What do you think? The poster i think is Spanish speaking and is using Google translator so it is a bit difficult to understand what he is asking. Hoping us IronHead guys can help him out.

Hopper
20th March 2012, 03:38
Sounds OK but idling too slow.
Adjust the idle speed screw. Also named throttle stop screw.
Idle speed screw is on the back of the carburetor.
It adjusts the movement on the return of the throttle cable.
Try screwing it one quarter turn and you will hear the engine go faster or slower.

It is screw number 10 in the pic below.

http://i249.photobucket.com/albums/gg220/ozhopper/kehin.jpg

You may get smoother running by adjusting the idle mixture screw on the top of the carburetor. Screw number 12.
This adjusts the flow of gasoline at idle.
Some later model carburetors may have a plug over this screw. Drill it out so you can see the screw below the plug.

Likemlouder
20th March 2012, 03:48
i think he is trying to get rid of what we all try to get. the potato potato sound. higher idle will help sounds like a shove to me God Love Em :D

Hopper
20th March 2012, 03:51
Also, you said you have 180 main jet and 68 slow jet.
These jets may be too too small for a Shovel with straight/free pipes.
On my Ironhead Sportster, I use a 75 or 80 slow jet with "free" pipes.
This slow jet affects idle.

A 1/32 inch drill will give you a .80mm hole.

IronMick
20th March 2012, 12:46
The idle mixture screw on the top of the carburetor, screw number 12, is also called the pilot screw. This procedure should help to set it ...

Setting The Pilot Screw on Your IronHead
http://xlforum.net/vbportal/forums/showthread.php?t=71361

Pan-Shovel-head51-79
20th March 2012, 13:35
Spark plugs a nice medium gray or tan color.
I have the pilot jet set at 2 1/2 turns out from seated.

IronMick
20th March 2012, 18:12
You may want to install a larger slow jet and get the pilot screw down to between 1/4 and 1,1/4 turns out; could easily take a #75 or perhaps even a #88.

Some useful information in this Sticky thread. ...

How to tune Keihin carbs - links
http://xlforum.net/vbportal/forums/showthread.php?t=276157

But the bike sounds very good to me. I do not hear a problem.

Hopper
21st March 2012, 03:53
Yes definitely need a bigger slow speed jet if the idle mixture/pilot screw is 2-1/2 turns out.
With the right slow speed jet, the pilot screw will work best at about one turn out.

Pan-Shovel-head51-79
21st March 2012, 23:41
and if I put the original exhaust?

IronMick
22nd March 2012, 02:07
If you change the exhaust you will probably have to adjust the pilot screw again. Probably not by much; maybe 1/4 turn, not more than 1/2.

Hopper
22nd March 2012, 02:56
Easier than changing the exhuaust, drill out the low speed jet with a 1/32" drill.

paraord
22nd March 2012, 12:12
That Idle sounds great. Just like my shovel. also jets are cheap I would get a new jet over drilling out an old one. I will check my manuals for the shovels when I get back in town this weekend if he doesnt have it figured out, or If i have a minute tonight I will run thru a PDF.
Hey Pan shovel you might want to try out shovelhead.us for a forum that specializes in shovels. Im a member over there because I have a shovel too, same username.
Great info from both sides

Pan-Shovel-head51-79
22nd March 2012, 22:56
with the change of the jets, increased fuel consumption or not?

paraord
22nd March 2012, 23:06
with the change of the jets, increased fuel consumption or not?

Well yea maybe a tiny bit, but it will be running properly.

Pan-Shovel-head51-79
23rd March 2012, 00:14
thank you all, I will go to the jets origin for FLH models 165 and 70

paraord
23rd March 2012, 11:33
:tourLet us know how she runs when you switch out those jets!

Pan-Shovel-head51-79
27th March 2012, 08:30
can someone send me the jet origin for FLH models 165 and 70 or the one that best suits my bike and repair kit including spring, washer and o-ring mixture screw please, here in Spain is difficult for old carburetors, me get payment address, can not find anything on ebay.
thanks

Pan-Shovel-head51-79
27th March 2012, 08:34
someone suggested that I change to a CV, but I have to change filters and other things and not let me pocket

Hopper
27th March 2012, 09:35
can someone send me the jet origin for FLH models 165 and 70 or the one that best suits my bike and repair kit including spring, washer and o-ring mixture screw please, here in Spain is difficult for old carburetors, me get payment address, can not find anything on ebay.
thanks

You can buy all the Keihin parts you need from www.jpcycles.com
They take international credit card payment and ship internationally.
Tell them to ship by USPS Priority Mail. It is cheapest and fast.
I use JPCycles for parts to Australia all the time. Always very good service.

Buy their most expensive 'Deluxe" Keihin rebuild kit. The cheaper kits are not very good.
If they do not have the jet size you need, email them and they will get it for you.

Take a look here
http://www.jpcycles.com/search/search?Context=28012737&Ntt=Keihin&Ntk=All

And at their hardcopy catalog here
http://www.jpcycles.com/catalog/2012harleycatalog/?entrypage=471


No need to convert to a CV carb. The Keihin is a good carb, with the right jets etc.

.


.

IronMick
27th March 2012, 13:26
with the change of the jets, increased fuel consumption or not?

No increased fuel cunsumption with larger jets. The fuel mixture will be better, the engine will run better, you will twist the throttle grip less to get the same speed as before.