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TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: mystic red on June 18, 2011, 04:58:39 PM

Title: Idle Ajustment?
Post by: mystic red on June 18, 2011, 04:58:39 PM
How do you adjust the idle on a K1100? Is it possible? I got mine back together after rehabbing the intake manifolds and it idles a little high now. I thought syncing the throttle bodies would take care of it but if anything it gets higher the closer I get to getting it synced.
Title: Re: Idle Ajustment?
Post by: johnny on June 18, 2011, 05:15:33 PM
i adjust my idle with the choke lever...

sent from johnnys droid
Title: Re: Idle Ajustment?
Post by: frankenduck on June 18, 2011, 05:20:49 PM
You can adjust the cable up at the throttle perch end.  Pull the boot back.
Title: Re: Idle Ajustment?
Post by: mystic red on June 18, 2011, 05:29:42 PM
I adjusted the throttle cable so there is a little free play already. No love.
When syncing the TB #1 is the front most TB, right?
Title: Re: Idle Ajustment?
Post by: frankenduck on June 18, 2011, 06:06:34 PM
Yes, the forward cylinder is number one.  You could use any TB as your reference TB though.
Title: Re: Idle Ajustment?
Post by: Scott_ on June 18, 2011, 06:49:34 PM
You sure you don't have a vac leak somewhere. That will give u a high idle.
Title: Re: Idle Ajustment?
Post by: frankenduck on June 18, 2011, 06:53:39 PM
You sure you don't have a vac leak somewhere. That will give u a high idle.

He just replaced the stuff above and below the TBs to fix an air leak.

Mystic Rod: My bikes idle a little fast.  I don't care.
Title: Re: Idle Ajustment?
Post by: johnny on June 18, 2011, 08:10:03 PM
mystic reb...

how many rpms you got on idle... the motoheap idles at 1500 rpms with the choke lever closed...

bye the way... that choke lever is a proficient cruise controller...

j o
Title: Re: Idle Ajustment?
Post by: Scott_ on June 18, 2011, 08:24:00 PM
You sure you don't have a vac leak somewhere. That will give u a high idle.

He just replaced the stuff above and below the TBs to fix an air leak.


I know. Still doesn't mean he couldn't have missed something. BTDT

To lower the idle you could turn ALL the brass adj screws in equally.
Title: Re: Idle Ajustment?
Post by: mystic red on June 18, 2011, 09:02:52 PM
You sure you don't have a vac leak somewhere. That will give u a high idle.

You're kidding me, right? That's what started this whole thing. ;)
No it's not that high, maybe 1200 RPMs.
Duck, why do you open the brass screw 1 1/2 turns? The reason I ask is when they are more closed the idle is lower.
#1 is the only one that I can't zero so I am using #4 as a constant. Then 2 and 3 will zero to 4. Don't know why #1 is being a pain in the ass.

Edit: just read the above posts. Missed em earlier. Will check for leak and try the brass screw thing later. Thanks.
Title: Re: Idle Ajustment?
Post by: johnny on June 18, 2011, 09:22:47 PM
mystic reb... the bug has never idled less than 1500 rpm n you know that moe screams like a stump hugging big giant poodle...

j o
Title: Re: Idle Ajustment?
Post by: frankenduck on June 18, 2011, 09:28:12 PM
If you can't synch #1 then you might still have an air leak.  Git yer propane out.

I do one and a half turns because I read it in an Eilenberger post somewhere and he knows more about this stuff than I do.
Title: Re: Idle Ajustment?
Post by: Scott_ on June 18, 2011, 10:14:50 PM
Another thought came to my mind.
When was the last time you checked your valve clearances?
Title: Re: Idle Ajustment?
Post by: frankenduck on June 18, 2011, 10:17:56 PM
Probably just a burned valve or leaking head gasket.  Nothing to worry about.
Title: Re: Idle Ajustment?
Post by: mystic red on June 18, 2011, 11:26:28 PM
If you can't synch #1 then you might still have an air leak.  Git yer propane out.

I do one and a half turns because I read it in an Eilenberger post somewhere and he knows more about this stuff than I do.

Did the propane. Negative. Used the #4 as a constant, backed out 1 turn which lowered the idle. #3 & #4 synched at about 1 turn out and #1 3 turns out.
Valves were checked about 20K ago, should be good.
They are synched now at the specified turns. Don't know why #1 is out so much but I had a tech do it once a few years ago and he said he had problems also in getting right to specs. What do ya think? Good to go?
Title: Re: Idle Ajustment?
Post by: mystic red on June 18, 2011, 11:28:00 PM
Probably just a burned valve or leaking head gasket.  Nothing to worry about.

Aren't you just a ray of sunshine. ;D
Title: Re: Idle Ajustment?
Post by: frankenduck on June 19, 2011, 12:44:09 AM
Probably just a burned valve or leaking head gasket.  Nothing to worry about.

Aren't you just a ray of sunshine. ;D

Just yanking your chain.  Exhaust valves are subjected to a lot more heat than intake valves
Title: Re: Idle Ajustment?
Post by: mystic red on June 19, 2011, 12:46:47 AM
If you can't synch #1 then you might still have an air leak.  Git yer propane out.

I do one and a half turns because I read it in an Eilenberger post somewhere and he knows more about this stuff than I do.

Did the propane. Negative. Used the #4 as a constant, backed out 1 turn which lowered the idle. #3 & #4 synched at about 1 turn out and #1 3 turns out.
Valves were checked about 20K ago, should be good.
They are synched now at the specified turns. Don't know why #1 is out so much but I had a tech do it once a few years ago and he said he had problems also in getting right to specs. What do ya think? Good to go?
Title: Re: Idle Ajustment?
Post by: johnny on June 19, 2011, 01:05:02 AM
dude... get aaa with the 200 mile tow n ride it till it wont move...

j o
Title: Re: Idle Ajustment?
Post by: mystic red on June 19, 2011, 11:51:04 AM
From the BMWOA guru:

Quote
One turn is enough and three not excessive provided they are balanced and the idle is acceptable. Number 1 out three turns is a sign that #1 draws a bit less air than the other three. Valve stem/head deposits maybe. Nothing to worry about but check it again in 5K miles or so (or whenever) to see what is changing if anything.
__________________
Paul Glaves - "Big Bend", Texas U.S.A
"The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
http://www.bigbend.net/users/glaves (http://www.bigbend.net/users/glaves)

So I'll take our guru's advise and "ride it till it won't move."
Title: Re: Idle Ajustment?
Post by: frankenduck on June 19, 2011, 12:08:44 PM
If Glaves says one is enough then that's good enough for me.

You might want to take #1 out and see if it's dirty.  They just screw right out and right back in.  Not a bad idea to clean all of them while you're at it.  While you have them out you can polish their tops with a Dremel to make them all shiny. 8)

Title: Re: Idle Ajustment?
Post by: mystic red on June 19, 2011, 12:12:45 PM
If Glaves says one is enough then that's good enough for me.

You might want to take #1 out and see if it's dirty.  They just screw right out and right back in.  Not a bad idea to clean all of them while you're at it.  While you have them out you can polish their tops with a Dremel to make them all shiny. 8)



Good idea, I'll check them out.
Title: Re: Idle Ajustment?
Post by: Scott_ on June 19, 2011, 01:42:18 PM
MR, if you say that your previous mechanic also commented on having troubles with #1 the same as you are, almost sounds to me like a butterfly adjustment could improve the situation.
You know the painted screws your "not supposed" to touch.
Title: Re: Idle Ajustment?
Post by: mystic red on June 19, 2011, 03:16:33 PM
MR, if you say that your previous mechanic also commented on having troubles with #1 the same as you are, almost sounds to me like a butterfly adjustment could improve the situation.
You know the painted screws your "not supposed" to touch.


Hi Scott, yea Clymers says to throw your $800 plus throttle assembly away if you have touch these. ;D
Got a link to the procedure handy?
Title: Re: Idle Ajustment?
Post by: Scott_ on June 19, 2011, 03:20:57 PM
I'll take a look on my other computer, but I think I have a pdf on it somewhere. I also think I sent Drake a copy of it a while back.

It had been posted on IBMWR a number of years ago but was removed.
Title: Re: Idle Ajustment?
Post by: frankenduck on June 19, 2011, 03:24:04 PM
Underscore: If'n you find it then please post it in the Lieberry as an atttachment.   (Click "Additional Options..." below the posting text box.)
Title: Re: Idle Ajustment?
Post by: Scott_ on June 19, 2011, 04:02:43 PM
I replied to your write-up and attatched it there.
Title: Re: Idle Ajustment?
Post by: frankenduck on June 19, 2011, 04:06:00 PM
Great. Thanks.
Title: Re: Idle Ajustment?
Post by: mystic red on June 19, 2011, 06:48:38 PM
Thanks Scott! Something to mess with this winter. Don't think I'm going to mess with it til then.
They do seem a little out of adjustment. If I just push down on the throttle rail with my finger the idle goes down to were it should be. Nothing holding it up, it just doesn't quite close.
Title: Re: Idle Ajustment?
Post by: frankenduck on June 19, 2011, 06:58:45 PM
Doesn't hurt to spray some silicone lubricant on the return springs.
Title: Re: Idle Ajustment?
Post by: Scott_ on June 19, 2011, 07:03:55 PM
From the way the article was written, it sounds like the author was working on a K75.
When I did my 2 bikes IIRC I used cyl #3 as my base because the throttle cable attaches to that butterfly most directly without adjustable linkage in between the butterfly and the cable attachment.
I set my throttle lock and went from there. 3 to 4, then 3 to 2, and finally 3 to 1. After that then the brass screws were adjusted for fine balance and final idle set. All using just my TwinMax.
If I had made any adjustment to #4 I then also checked my TPS settings, and choke settings last.

Like Dr.Duck suggested a little lubrication doesn't hurt, make sure all is freed up.
Title: Re: Idle Ajustment?
Post by: Uffda on June 19, 2011, 08:58:35 PM
If I just push down on the throttle rail with my finger the idle goes down to were it should be. Nothing holding it up, it just doesn't quite close.
Disclaimer: K75RT is my first bike and right now I don't know enough to be good on the diagnostics, just good enough to be dangerous.  Anyway, What you just described above is what mysteriously happened to my K75.  What I found was causing it but have no idea how it happened, is the TPS moved by itself to do just that:  The TPS was turned CW enough to slightly hold the throttle rail open, which I could close and bring idle down to normal by pressing on the throttle linkage.  While checking for every kind of linkage hangup, I finally removed the TPS and discovered the idle was correct with it off.  I reattached TPS, reset and tightened it up, and all's well ...... except for the inadvertent turn I made to the blue painted screw between #2 and #3 TB. :(  Still wondering how to proceed with that, even after reading the PDF attachment over on the TB synch thread.
Title: Re: Idle Ajustment?
Post by: mystic red on June 19, 2011, 09:13:54 PM
Quote
The TPS was turned CW

Excuse my ignorance but what is CW?
Title: Re: Idle Ajustment?
Post by: Scott_ on June 19, 2011, 09:19:44 PM
Quote
The TPS was turned CW

Excuse my ignorance but what is CW?

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