K11 Owners Group

RobWheatley · Posted: Sun Sep 06, 2009 8:35 pm Post subject: TB Sync

Hi all.
Carrying with the work on my LT I did a TB sync yesterday, got all the readings the same at idle but noticed when I open the throttles and hold it at about 3000rpm numbers 1&2 are a higher vac than 3&4, the difference is about 2in of pressure on my guage (needle type not column) I also noticed that there is no laquer on the screws that adjust the links between the TB's of 1-2 and 2-3.
Im wondering if a PO has played with the adjusters and that 1&2 are not opening as much as 3&4. If that is the case is there a right method for resetting them?

Rob
_________________
1999 K1100LTIC Smooth and Quiet Smile

Cruise, BFD & HID
1996 K1100RS. dead but not forgotten.

RAL88 · Posted: Mon Sep 07, 2009 7:34 am Post subject:

Hey Rob,

Send me your e-mail and I can send you a tech article on how to sync the butterfly valves.
_________________
Rich

"If it ain't broke, take it apart and make it work better"
*************
'96' K1100LT-SE
'97' R850GS-R

max · Posted: Mon Sep 07, 2009 8:58 pm Post subject:

+1 for Rich's comment - have done the "do not touch" sync here myself, also for a fix to a "probable play" from a PO... Possible to do, but take your time and have the engine hot but with a cooling fan on hand!

BTW - the adjustments are VERY sensitive - allow plenty of tries, "ping" the throttle back a few times too to make sure it's really settled on the little slack-take-up springs and BE GENTLE with the locknuts.

Also - keep in mind the adjustment range for your idle speed... if you end up with synced TBs but an idle of 2000 and no "slack" to bring it back down, you'll kick yourself (don't ask how I know).

Max

PS - Also also - before you dig in - have you checked/excluded the other possible contributors/culprits:

- valve clearances
- any change of air leaks between the TBs and heads (perished intake runners, leaks around injector o-rings, leaks around adjustment screws (little o-rings IIRC)
- any crud on the throttle butterflys themselves, or in the bores of the vacuum tap pipes

RobWheatley · Posted: Tue Sep 08, 2009 11:41 am Post subject:

I have checked there are no leaks (carb cleaner when at idle around the TS's and intake ports) vacuum taps are clear, valve clearances are correct, plugs etc but not looked at the butterflys for crud, seems funny that it 2 next to each other that are out and they are the ones with no lacquer.

Will have a go at the procedure that Rich has kindly sent and report back on my findings.

Rob.
_________________
1999 K1100LTIC Smooth and Quiet Smile

Cruise, BFD & HID
1996 K1100RS. dead but not forgotten.

Wrigsby1 · Posted: Sat Sep 12, 2009 8:10 am Post subject:

My K11 might also have had the butterfly valves messed with as I have a prob with the initial throttle action being smooth. As I also have an R11GS, this is minor compared, but I will ask Rich for the info anyhow. One of my "adjusters" has half it's head broken off possibly showing a botched attempt previously by the ignorant to set the TB balance, duh!

As I have changed leaking manifolds and a cracked breather tube I wonder if a PO has messed with ths butterfly settings rather than check and change the dam manifolds!! Some folk think like that...

Ta
Guy

RobWheatley · Posted: Sat Sep 12, 2009 12:05 pm Post subject:

They might have adjusted things to compensate for the leaks.

Well I did the butterfly sync on my LT as described in the link from Rich, took me about 1 1/2 hours to do it.
Got them all the same at different throttle opening then reset the brass sync screws, Idle speed is just under 1000 rpm and its even smoother now, it was a little bit rough when on small throttle openings and when cold on choke (fast idle) but now a lot better.
Thanks Rich for the info.
_________________
1999 K1100LTIC Smooth and Quiet Smile

Cruise, BFD & HID
1996 K1100RS. dead but not forgotten.

Wrigsby1 · Posted: Mon Sep 14, 2009 7:17 pm Post subject:

Thanks Rich +2

I have synced my TB's via the "never, ever touch" screws and now all is well. Rob hit my train of thought exactly with the PO('s) messing with them in order to compensate from increasingly leaky throttle manifolds and breather tube.

As I sorted a these leaky bits the TB's became more tricky to get a good balance resulting in poor pick up off a closed throttle which = crap slow control. The fix theory is simple and the execution just takes a bit of thought and care.Two of my TB grub screws were damaged by previous idiot's duff mechanics!

I have had K's before so knew you could get them a dam sight smoother than this. I also have a few good tips for balancing K100 8 valves if anyone needs them.

Cheers Rich and Rob,

G

RobWheatley · Posted: Tue Sep 15, 2009 6:30 am Post subject:

Just a thought.

As it is quite easy to check it might be worth doing if any others have K's that run a little bit roughly, As long as you are gentle with the adjustment screws and locknuts and use 4 vac guage's it is really quite simple to do and really does make a big difference.

You do need a good screwdriver so you dont have to put too much downwards pressure in the adjuster or you will compress the spring underneath and throw the butterfly out, if you do just blip the throttles a few times to settle them back and try again. I also kept the locknuts quite tight when turning the screw so as not to alter the setting by doing the locknut up.

Rob
_________________
1999 K1100LTIC Smooth and Quiet Smile

Cruise, BFD & HID
1996 K1100RS. dead but not forgotten.

RAL88 · Posted: Tue Sep 15, 2009 9:19 am Post subject:

I actually use the carb adjuster that I have for my Honda. It is the same size as the the nut on the TBs and it is a long neck screwdriver that go through a hollow tube with a socket on the end. It lets you hold the screw while tightening the nut so you don't change the setting and you don't have to put any downward pressure on it.

http://www.sudco.com/motionpro.html#adj
_________________
Rich

"If it ain't broke, take it apart and make it work better"
*************
'96' K1100LT-SE
'97' R850GS-R

RobWheatley · Posted: Tue Sep 15, 2009 9:36 am Post subject:

Cool tool, got to get me one of them.
_________________
1999 K1100LTIC Smooth and Quiet Smile

Cruise, BFD & HID
1996 K1100RS. dead but not forgotten.