ST1100 Carb removal/rebuild

Joined
May 30, 2007
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Grand Junction, Colo.
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92 ST1100
Its been a few years, but I think you can see under the carbs if you removed the gas tank before removing the carbs. You might need a mirror to get the right angle, but I seem to recall that there was a certain amount of visibility under there after you put the carbs back on. Can't remember for sure though.

re: coolant elbows question, two reasons to replace them, 1) people have tried to re-use them and have had issues with them cracking, either upon re-installation, or shortly thereafter. 2) the original O-ring will be a gooey mess. For the few extra bucks they cost its not worth the risk of re-using the old ones, and you'll need new O-rings too.
OEM from Honda, the new coolant elbows come with new 0-rings;).
 
Joined
Mar 13, 2012
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5,045
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soCal
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'97 ST1100
STOC #
687
Its been a few years, but my memory says the O-rings are separate from the coolant elbows, its the water pump that ships with the O-ring, but isn't advertised that way on the fiche.

I have an extra water pump O-ring, but no spare elbow rings, and ordered them separately in both cases. I ordered mine in 2013.
 
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Jun 3, 2006
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3,514
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British Columbia
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2021 RE Meteor 350
Its been a few years, but my memory says the O-rings are separate from the coolant elbows, its the water pump that ships with the O-ring, but isn't advertised that way on the fiche.

I have an extra water pump O-ring, but no spare elbow rings, and ordered them separately in both cases. I ordered mine in 2013.
My experience with the two O-rings concurs exactly with Doug's. I bet there are a lot of water pump O-rings sitting in garages.
 
Joined
Mar 12, 2006
Messages
226
Location
Brewerton, NY
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ST1100/ST1300
STOC #
949
Thanks Adam. I did tell him it was a CA bike. I'm good on the sync... please explain more on the 'tune' part?
Sorry for delay in response. I don't get out that much...:)

Your V4 carb guy will more than likely set the idle mixture screws at a generic setting, which may not be proper for your particular ST, and/or your area. It would be best to "tune" the idle mixture/pilot circuit for your bikes needs when you get the carbs back. Your carb guy specializes in Magna/Sabre and possibly VFR's. While similar in design to the ST, they are still different. Remember that you have an emission bike with slightly lazy camshafts. You'll need to start off at around 1-3/4 to 1-7/8 turns out from lightly seated for the mixture screws, which will get you really close to were you need to be.
 
Joined
Sep 10, 2011
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2,210
Location
West Michigan
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'98 ST1100
STOC #
8470
OEM from Honda, the new coolant elbows come with new 0-rings;).
Interesting, mine didn't come with o-rings. Maybe they did at one time, but not more recently. I ordered the latest pair of elbows a few months ago. Getting parts together for my spring PM.

I replaced the hoses to the elbows with 3/4 " silicon heater hose about 5 years ago. I'm curious to see how they are holding up. I bit the bullet and ordered some OEM hoses when I ordered the elbows.
 
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paulcb

paulcb

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Joined
Jun 4, 2013
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Celina, TX
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'97/'01 ST1100 ABSII
STOC #
8735
Its been a few years, but my memory says the O-rings are separate from the coolant elbows, its the water pump that ships with the O-ring, but isn't advertised that way on the fiche.

I have an extra water pump O-ring, but no spare elbow rings, and ordered them separately in both cases. I ordered mine in 2013.
My elbows did not come with o-rings. Glad I ordered them separately. I still don't have my carbs back but he did just finish them last night. Some comments from him about my carbs...
  • Slow jets were clogged.
  • #3 float seat had some nasty under it.
  • All stock jetting but I added a 2nd shim to the jet needles as owners report this as a good midrange fix.
  • Nice rack. Went together easy, nice and tight.
  • Chokes and throttle plates are synched. Get it installed, feed them fresh clean fuel and go ride.
  • You’ll find a screw in the slot where the idle cable goes. No cable so I needed that to set the synch. When you install the cable screw it in til the throttle plate just cracks open about the thickness of a sheet of paper. You’ll be adjusting it again once the bike is warmed up to set the idle speed.
  • I have never worked on an ST but it looks like a real PITA to install the carbs on one.
Hope to get them installed this weekend. I already installed new water elbows, hoses and clamps. Getting to the clamps of the hoses at the thermostat housing is 'difficult' at best, since I didn't pull the housing. The top clamp on the lower radiator hose was the most problematic though... I ended up cutting the clamp to get it off.
 
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paulcb

paulcb

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Anyone local to me (Dallas) that would loan me the driver for the ST1100 carb mixture screws?
 
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paulcb

paulcb

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Got the carbs installed, synced and everything back together over the weekend. What a job... I'm tired! Took it for a test ride before I put all the plastic back on... ran well with no leaks or gas smell. The next test will be commuting this week and maybe WinterSTOC this weekend. Thanks to everyone for your help and input.
 
Joined
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Grand Junction, Colo.
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92 ST1100
My elbows did not come with o-rings. Glad I ordered them separately. I still don't have my carbs back but he did just finish them last night. Some comments from him about my carbs...

[FONT="][COLOR=#1F497D][FONT=Calibri]-[FONT="] [/FONT][/FONT][/COLOR]Slow jets were clogged.[/FONT]
[FONT="][COLOR=#1F497D][FONT=Calibri]-[FONT="] [/FONT][/FONT][/COLOR]#3 float seat had some nasty under it.[/FONT]
[FONT="][COLOR=#1F497D][FONT=Calibri]-[FONT="] [/FONT][/FONT][/COLOR]All stock jetting but I added a 2[SUP]nd[/SUP] shim to the jet needles as owners report this as a good midrange fix.[/FONT]
[FONT="][COLOR=#1F497D][FONT=Calibri]-[FONT="] [/FONT][/FONT][/COLOR]Nice rack. Went together easy, nice and tight.[/FONT]
[FONT="][COLOR=#1F497D][FONT=Calibri]-[FONT="] [/FONT][/FONT][/COLOR]Chokes and throttle plates are synched. Get it installed, feed them fresh clean fuel and go ride.[/FONT]
[FONT="][COLOR=#1F497D][FONT=Calibri]-[FONT="] [/FONT][/FONT][/COLOR]You’ll find a screw in the slot where the idle cable goes. No cable so I needed that to set the synch. When you install the cable screw it in til the throttle plate just cracks open about the thickness of a sheet of paper. You’ll be adjusting it again once the bike is warmed up to set the idle speed.[/FONT]
[FONT="][COLOR=#1F497D][FONT=Calibri]-[FONT="] [/FONT][/FONT][/COLOR]I have never worked on an ST but it looks like a real PITA to install the carbs on one.[/FONT]

Hope to get them installed this weekend. I already installed new water elbows, hoses and clamps. Getting to the clamps of the hoses at the thermostat housing is 'difficult' at best, since I didn't pull the housing. The top clamp on the lower radiator hose was the most problematic though... I ended up cutting the clamp to get it off.
Souds like your mechanic didn't know to spray a shot of silicone on inside of those carb boots before carb installation;):).
 
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paulcb

paulcb

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'97/'01 ST1100 ABSII
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8735
Souds like your mechanic didn't know to spray a shot of silicone on inside of those carb boots before carb installation;):).
Well, my mechanic was me, and I did lube the carbs and boots with a little vaseline. They slipped right in to the boots, with a little persuasion. ;)
 
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paulcb

paulcb

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8735
Well, I've commuted on it for a whole two days plus a few more miles here and there... lots of idle time, acceleration/deceleration and a few 'high speed' runs. It seems to run perfect. I thought it ran perfect before the carb rebuild, but now it really does. I'd say it's about 5-10% stronger, but maybe that's just my hopeful expectations talking.
 
Joined
Jan 15, 2016
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76
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Moorpark, CA
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2002 Honda ST1100
On the Boot insulators, I am replacing them but can't remember which way they go. Can't even remember which is right side up.
 
Joined
Oct 19, 2009
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199
Location
Nor Cal
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2005 ST1300A
I've wondered about the mat material. I have some heavy rubber roofing material that I've thought of cutting (there is a template here somewhere), but not sure if it, or something else, would tolerate the heat.
I’d be inclined to buy a 1/16” thick silicon rubber sheet. That will have a much higher heat tolerance
[/QUOTE]
 
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