question re float height


Information and questions on GL1200 Goldwings (1984-1987)
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froche
Posts: 143
Joined: Wed Mar 12, 2014 1:56 pm
Location: Vista, ca
Motorcycle: 1985 Goldwing Aspencade (GL1200A

Former bikes;
2000 R1100RT
2005 Suzuki Bandit
1979 Yamaha XS1100
1978 Yamaha XS1100 Special
1990 Yamaha XV250
1980 Yamaha XV750
1979 Honda CB750
1968 Triumph Bonneville T120
1973 Honda CB450
1968 Harley Davidson Sportster
1974 Honda CB750
1968 Honda CL72

question re float height

Post by froche » Wed Nov 21, 2018 10:42 pm



So my carbs are clean and work "fine" however I get poor fuel mileage, about 26 mpg. Verified by several tanks over some time.

Bike;1985 GL1200A

The carbs are:
synced
clean
no popping
new air filter
new gas filter
fuel mixture screws about 1.5 to 1.75 turns out

starts and runs fine
cold idle after turning off the fuel enrichment 960 RPM, stator reports 12.5 volts
accelerates well
gas cap ok
no leaks when parked

I keep thinking float level..
What do you think and what height to check for and possibly set to?
Also any idea what weight the floats should be? Or how to check for cracked pinholed floats.
What about float needle and seat?



User avatar
virgilmobile
Posts: 8720
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: question re float height

Post by virgilmobile » Thu Nov 22, 2018 12:08 pm

Pull all 4 spark plugs..identify each one as what cylinder it came from.
"Read" each plugs condition/color..
What does each one look like?

froche
Posts: 143
Joined: Wed Mar 12, 2014 1:56 pm
Location: Vista, ca
Motorcycle: 1985 Goldwing Aspencade (GL1200A

Former bikes;
2000 R1100RT
2005 Suzuki Bandit
1979 Yamaha XS1100
1978 Yamaha XS1100 Special
1990 Yamaha XV250
1980 Yamaha XV750
1979 Honda CB750
1968 Triumph Bonneville T120
1973 Honda CB450
1968 Harley Davidson Sportster
1974 Honda CB750
1968 Honda CL72

Re: question re float height

Post by froche » Thu Nov 22, 2018 1:15 pm

Need to check the plugs now, but I have been thinking and trying to figure it out. The last time i pulled the plugs they were all dark showing too much fuel, and about the same as each other.

User avatar
virgilmobile
Posts: 8720
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: question re float height

Post by virgilmobile » Fri Nov 23, 2018 3:17 pm

The book says 7.5mm
They must be the same on each half and just resting on the needle buffer plunger..Not compressing it...
Exactly 7.5 mm..on the money...
A quick test for you..
Start the bike and warm up a few minutes...
Turn the idle screw to increase the idle to 1500-2000rpm..let it run a few seconds there stable..
Turn off the fuel and wait...as it consumes fuel,if it just starts to slow down,the float level is ok..if it actually increases rpm for a few seconds then starts to drop,your fuel level is too high.

froche
Posts: 143
Joined: Wed Mar 12, 2014 1:56 pm
Location: Vista, ca
Motorcycle: 1985 Goldwing Aspencade (GL1200A

Former bikes;
2000 R1100RT
2005 Suzuki Bandit
1979 Yamaha XS1100
1978 Yamaha XS1100 Special
1990 Yamaha XV250
1980 Yamaha XV750
1979 Honda CB750
1968 Triumph Bonneville T120
1973 Honda CB450
1968 Harley Davidson Sportster
1974 Honda CB750
1968 Honda CL72

Re: question re float height

Post by froche » Tue Nov 27, 2018 10:13 pm

Ordered a float height gauge. waiting for it.
Had to change the brake pads (all 3) so I cleaned off the pins that hold the pads aligned even though they were fairly free... took a few taps with a hammer and a pin punch but not too hard. Thee plugs will be removed. inspected and also changed after the float height tool arrives (gotta take of the tupperware to remove and check carbs so i'm going to do it at the same time).

Haven't tried shutting off the fuel to see how the motor reacts. I assume that if the floats allow too much gas in and shutting off the fuel makes the carbs go from a rich mixture to a correct one and finally a lean one. So it goes from running to running correctly increasing in speed to running poorly as the mixture goes to lean.

User avatar
virgilmobile
Posts: 8720
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: question re float height

Post by virgilmobile » Wed Nov 28, 2018 7:32 am

At 1500-2000rpm my bike did run well but not great.As I shut off the fuel it ran stable for a bit.However it was rich..as the fuel was consumed,it increased rpm for a short time as the fuel mixture approached "normal" then started to drop as it went lean.
Shutting off the fuel is like adjusting the float (fuel) level to obtain the correct fuel mixture.
I had to readjust my floats by 1.5mm



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