Carburetor fuel delivery...Need some advice here

Joined
Apr 30, 2014
Messages
141
Location
Las Vegas, , Nevada
Bike
94' 1100 ABS
This is a 94' 1100 abs/tcs. I pulled the carb bank again to replace the jets, clean it out and try to fix the delayed return to idle after coming off the throttle when shifting. I put new new jets in, new air/fuel screws spring and O ring( set at 1 7/8 turn out), cleaned the bowls, adjusted the float seats, and cleaned the internal and external body. After re-install it was dumping fuel from the bottom of the bank, I'm not sure from where from. After a bit the fuel leakage stopped and the bike seemed to run good. I then tried a simple snorkel synch adjustment. I did not do the idle drop procedure. It seemed to be idling fine. Took it around the block and it was super boggy at low rpm. Before I put it away for the night, it was difficult to even rev the motor and seemed to be losing power.

Next day:

Bike will not start in any configuration. I got it to start for a few seconds with starting fluid and then dies. Suspected bad fuel pump. Pump appeared to be putting out very little fuel. I bypassed the pump and used a temporary gravity tank. Still no start. Used starter spray with the gravity tank with same result, starts for a second and dies with fuel available.

Besides starting over, I am at a complete loss of what to do next ???

Any ideas are appreciated, thanks.
 
Joined
Mar 12, 2006
Messages
226
Location
Brewerton, NY
Bike
ST1100/ST1300
STOC #
949
First thing... Throw away the starting fluid.

If the bike still has the vacuum petcock, bypass it and retry.

Perform the fuel pump test per service manual to check fuel output. Also make sure the pump is getting full voltage and ground.

If everything above checks out perfectly and it still won't start, leave the vacuum petcock bypassed and open up all the float bowl drain screws. Turn on / off, the key for several cycles and see if fuel is running through the carbs into a glass container. The drain hose is down by the right foot peg.
 
Joined
Aug 1, 2007
Messages
547
Location
Williamsport, PA
STOC #
4138
If you eventually figure the trouble is not the fuel system, could it be something in the ignition system?
Back in the early 80s I worked at a dealership. We had a customer bring back a almost new V45 Magna with the symptom of it not returning to idle when rolling off the throttle.
The other mechanic in the shop worked on it for two days, switching carbs with another bike and checking everything he could think of. I finally suggested we try a different set of ignition pulsers.
That cured the problem.
That part on the ST1100 is on the starter clutch parts diagram. Item #8
http://www.partzilla.com/parts/search/Honda/Motorcycle/1994/ST1100A+A/STARTING+CLUTCH/parts.html
 
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hotrod1
Joined
Apr 30, 2014
Messages
141
Location
Las Vegas, , Nevada
Bike
94' 1100 ABS
Thanks for the replies:

Everything checked out OK, but no fuel going through the carburetor. I had no choice but to remove the carb block again, it only takes ten minutes since I have done it several times on two 1100's now. Anyway, opened up the float bowls and they were a mess. The jets were fine though, but I cleaned entire carb again and now its reassembled. Install on the bike tomorrow and hopefully ready for a ride on Tuesday.

The books have the pilot screw preset any where from 1 7/8 for Canadian models and all the way to 2 5/8 out. I settled for 2 1/4 out to start. Hopefully I have better results tomorrow.

Thanks All.....
 
Joined
Mar 12, 2006
Messages
226
Location
Brewerton, NY
Bike
ST1100/ST1300
STOC #
949
2 1/4 turns out will be too much for your ABS model. Especially in the desert heat. You'd be better off at 1 1/2-1 3/4 as a default, until you can tune to your area.

ABS models have lazy emission camshafts. Less lift and duration than the standard model. Gotta go easy with the fuel...
 
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hotrod1
Joined
Apr 30, 2014
Messages
141
Location
Las Vegas, , Nevada
Bike
94' 1100 ABS
Really..The leanest initial setting in the service manuals is 1 7/8 out, then idle drop to tune. Some go as far as 2 5/8 turn out. Which make me wonder why there is such a big difference. Thanks for pointing this out afrymoyer, I need to have the initial setting done here in the next little bit, I want it all buttoned up today.
 
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hotrod1
Joined
Apr 30, 2014
Messages
141
Location
Las Vegas, , Nevada
Bike
94' 1100 ABS
If you eventually figure the trouble is not the fuel system, could it be something in the ignition system?
Back in the early 80s I worked at a dealership. We had a customer bring back a almost new V45 Magna with the symptom of it not returning to idle when rolling off the throttle.
The other mechanic in the shop worked on it for two days, switching carbs with another bike and checking everything he could think of. I finally suggested we try a different set of ignition pulsers.
That cured the problem.
That part on the ST1100 is on the starter clutch parts diagram. Item #8
http://www.partzilla.com/parts/search/Honda/Motorcycle/1994/ST1100A+A/STARTING+CLUTCH/parts.html
ThankYou
 
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