ST1100 Carb Sync

[swilliams1005]

I've searched the threads and i'm unable to find what im looking for. So here it goes. Since im going to be putting my bike back together in the next couple of days i wanted to replace the plugs and do a carb sync since i had to remove them to replace the coolant lines underneath. Does anyone have any instruction on the best way to do this i know i need the tool to do this but can't find one,, might not be searching i nthe right places on the web to find them. Thanks:biker:

 

[Mick]

i wanted to replace the plugs and do a carb sync since <SNIP> Does anyone have any instruction on the best way to do this i know i need the tool to do this but can't find one

I and many others use an SK Flow Meter. Much quicker and easier to use than a mercury manometer. This is where I got mine:

http://www.cbperformance.com/catalog.asp?ProductID=572

If you decide to order one be sure you order the SK model.


As to instructions on how to go about it, there is a write-up on Mike Martin's excellent website:

http://home.insightbb.com/~mmartin36/STE.htm

Mike's website is a great resource for ST1100 maintenance:

http://home.insightbb.com/~mmartin36/

 

[hawkeyeST]

http://home.insightbb.com/~mmartin36/

I have a Morgan CarbtuneII, which collects dust most of the time and a set of mercury styx that I favor. There is also an SK flowmeter that some folks like really well.

 

[Uncle Phil]

The SK Flowmeter makes it almost idiot proof on the ST1100. You will just need a really long Phillips screwdriver to get to the screws. I found by removing the bottom of the air cleaner housing it makes it a lot easier also.

 

[saaz]

I have the Morgan carbtune and the SK flowmeter. I use the flowmeter these days on the ST11 (the carbtune was more for my old inline 4 and any new fuel injected bikes I might get)

The SK is not taotally idiot proof, as I believe some people measure the wrong intake horn while adjust a carb screw, and wonder what is going on

 

[Ken H]

+1 on the SK Flowmeter. I have the Morgan Carb Tune synchronizer as well. I had the Morgan before the SK. The Morgan works well but the process is so much easier with the SK. If I had known I would have gotten the SK to begin with.

 

[Uncle Phil]

SAAZ - Come to think of it, there's not much out there that's totally idiot proof .... Never thought about sticking in the wrong horn.

 

[Gymbo]

+1 on the STE SK Flowmeter. If I can do it first try, just about anyone can. The only real tricky part as others have said is making sure you're reading from the correct snorkel for the carb you are intending to adjust. It's pretty clear if you remove the air cleaner base.

 

[saaz]

One suggestion if you might use the vacuum guages in the future is to put on slightly vacuum longer hoses.

My excuse for the wrong horn is that it was a longish maintenance day, pulling out and servicing the carbs, putting them back in, installing a cruise control and tidying up some other wiring.

John

 

[DAS]

Is an adapter needed to use a SK on the ST1100 or will it fit directly tot he air horns?

 

[STingray]

SAAZ - Come to think of it, there's not much out there that's totally idiot proof .... Never thought about sticking in the wrong horn.

UP, read my sig line again....

 

[saaz]

I am proud to be a better idiot..improving the species ) I just don't mind telling others in case they don't want to join the club...

 

[John OoSTerhuis]

Re: ST1100 Carb Sync - SK Flowmeter vs Mercury STicks

Here's another view on synchronizing carbs (below). I originally poSTed this to the old ST1100 email LiST. The only thing I'd add to it today is:

- if you use an SK single-handed, get a couple of 90? adapters or position a mirror so you can read the meter while turning the carb screws.

My dealer uses merc sticks and the Honda Service and Common manuals call for them. Measure the intake manifold vacuum or snorkle air flow, your choice... but I'll stick with my STicks, thanks.

IMHO, FWIW, YMMV yadda yadda.

Regards, John

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Subject:[ST-Riders] SK Flowmeter vs Carb Sticks Comparo
Date:9/1/2006 12:26:26 PM Central Daylight Time
From:STGhOOST@aol.com
To:st1100@st1100.com
--
Hello LiSTers,

As one of the very last things to do to get ready for WeSTOC, I just sync'd
The Grey GhOOST's carbs. My friend Bill Rankin had loaned me his new SK model
"STE Synchrometer Flow Meter" to try, so I decided compare it with my old
tried-n-true "Motion Pro Vacuum Carb Synchronizer."

Here's the short version: I'm keeping my mercury sticks.

Why? With the carb sticks I can sync the other 3 carbs' mercury vacuum
levels to within 2mm of the #4 base carb, sometimes all four dead-level. This
often requires almost imperceptable movement of the adjustment screws. Sync'g
with the flowmeter requires far more movement of the screw to get any change in
the meter reading and IMHO results in an imprecise 'tune' of the carbs. Let me
explain further...

Here's how I did my comparo. I performed my normal sync with the carb sticks
- removed tupperware until the fairing pockets were off, hooked up the carb
sticks (dunno why folks find this hard), start the engine and let it warm up,
adjust carbs to #4 IAW the manual. Gott'm within a whisker of each other...
bike sounds good. BTW, it was barely out of 'tune' since my last sync (#1: -
+3mm, #3: -5mm) some, what?...2 years and 8K ago.

Anyway, I then shut off the ST and removed the air cleaner cover. Restarting
the engine I notice the still hooked-up carb sticks show no appreciable
change... interesting. Then I measured all the carbs air inflow at the air horns
with the SK meter. They're all right at just under the #4 cylinder's reading
of "4" on the SK's scale. Cool... nothing wrong with my ole 'sticks.' ^)

However, [there's always a 'however', isn't there?] in the interest of a
thorough comparo, I then turned the #1 and #2 adjustment screws a good bit in
opposite directions and proceeded to do a sync with the SK meter. [the merc tubes
at this point were waaay outta 'sync'] At this point, the difference between
the two methods became apparent to me:

- the SK meter is far less sensitive to adjustment screw movement, taking
what in comparison to the merc sticks would be considered gross movement, just to
get the meter's red needle to move even its own width.

As a point of reference, at a reading of 3.5 on the SK, there's only one
needle width between there and the '4' on the scale. No wonder folks like this
method (measuring the air inflow instead of the intake vacuum) - readily turn
the adjustment screws a sixteenth or even an eighth of a turn and the SK will be
quite satisfied, showing the carbs "in sync" (while the mercury tubes at
those settings showed some cylinders as much as 3/4" off of #4).

BTW, turning the screws while trying to view the SK meter's needle is nearly
impossible as they point away from the side of the bike where that cylinder's
screw is located. Get a 90? attachment if you decide to go this route, or
plan on a trusted assistant to call out the numbers while you do the deed.

In fairness, I must say that at least subjectively, I only noticed a very
slight difference in the sound, or apparent 'smoothness,' of the engine with the
new SK tune compared to the carb sticks' state of tune/sync. Also, at this
point I didn't button up the GhOOST and go for a ride to see what the SK tune
felt like... not with the mercury tubes that far off. I put the air cleaner
cover back on, resync'd the carbs with the mercury tubes and called it done.

Anyway, if you're happy with your SK meter and your ST seems to run fine/up
to your expectations... fine. However, I'll stick with my old mercury tubes...
no need to change what ain't broke, IMHO. The SK is certainly portable, but
if you need to take one on the road with you because you have to resync
enroute, there's something wrong with your Honda.

BTW, I'm not totally unfamilar with flow meters, having used one for years
to sync the carbs on my 72 Jag XJ-6.

BTW2, I can ride my ST right after doing a carb sync. I just put on my old
pair of deerskin work gloves, remove the carb sticks' hoses and rehook the
cylinders' vac hoses. No burns. And timewise, using the SK or carb sticks is a
wash.

YMMV and probably will.

Just another data point...

Regards, John OoSTerhuis STOC 1058

http://community.webshots.com/user/stghoost
http://community.webshots.com/user/st1100greyghoost
http://community.webshots.com/user/stoc1058
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

[saaz]

I have been going to do a comparison between the two methods (SK and morgan carbtune, which I bought to do my inline 4) with both connected up, but have not bothered since neither seems better than the other on the road. One benefit with the carbtunes would be keeping the air box lid on, but this does not seem to make a difference at the end of the day. And I did put in longer vacuum hoses than standard to make it easier to use the carbtune. No need to use gloves or anything, as removing the vacuum hose caps and putting on the carbtune hoses is dead easy (US models may vary??). In between riding (far more important than working on the bike!) over the new year I will try and compare both methods, including any different readings using the low idle and higher idle methods. Seems everyone has their own way of doing it, and the ST11 is relatively forgiving. Free access to a dyno and 4 flowmeters hooked up electronically along with vacuum measurement would be the way to go, but I don't think I am the one to do it