mysterious vacuum line:


Information and questions on GL1100 Goldwings (1980-1983)
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mud/dauber
Posts: 10
Joined: Sun Aug 13, 2017 12:19 pm
Location: Independence, Kans
Motorcycle: 1980 Honda GL1100 standard

mysterious vacuum line:

Post by mud/dauber »



Calling all master mech's of the 1980 GL1100: I saw on another post about the 12 inch long vacuum line that spurs from the "T" joint connecting the auto spark advance (located at the back right of the engine) to the no. 3 carb port. But saw no respondents could explain it or where it connects to. Which brings us to my problem. I'm in the final stages of rebuilding my barn find and can't remember or find where that hose fits either! I don't remember removing it; no mention of it in my notes or in the manual; but it does have a spring clamp so must have come from somewhere. If I draw or blow through the line, only the slightest of air movement; unlike the other line which causes the diaphragm to noticeably move. I plugged it with the golf tee but I don't know why. Any ideas?
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skier
Posts: 186
Joined: Sun Jul 17, 2011 11:57 am
Location: Coon Rapids MN
Motorcycle: 2002 Gl1800 77k miles
2006 ST1300 14k miles -- sold in 2020 to a 75 year old
1987 GL1200I 135k miles -- sold in 2020 to an 80 year old
2009 Honda Silverwing 16k miles -- the wife's scooter

Re: mysterious vacuum line:

Post by skier »

Maybe a access point to test vacuum, that would normally be capped off?
mud/dauber
Posts: 10
Joined: Sun Aug 13, 2017 12:19 pm
Location: Independence, Kans
Motorcycle: 1980 Honda GL1100 standard

Re: mysterious vacuum line:

Post by mud/dauber »

Maybe. I am going to check to see if mine is clogged because very little air can move through it when I draw or blow in the end of it. If anyone out there has a 1980 standard gl1100, I wish they would see if they have the same set up from the carb to the advance diaphragm. See if there is a "T" junction and tell me (us) where that spur line goes to.
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DenverWinger
Posts: 1934
Joined: Thu Jun 23, 2011 2:20 pm
Location: Denver, CO
Motorcycle: (s)
1980 GL1100 STD Vetter (2005-)
1993 GL1500 Aspencade (2017-)
1983 Trav-Lite Camper (2010-)
Past rides
1972 CL350 (1980-1988) sold
1978 Suzuki GS550 (1985-2005) sold
1977 GL1000 (2002-2006) sold

Re: mysterious vacuum line:

Post by DenverWinger »

No Tee at all, just the line to the vacuum advance.....
♫ 99 Little Bugs in the Code, ♪
♪ 99 Bugs in the Code. ♫ :(
♫ Take one down, Patch it around, ♪
♫ 127 Little Bugs in the Code. ♫ ♪ :shock:

~Mark
mud/dauber
Posts: 10
Joined: Sun Aug 13, 2017 12:19 pm
Location: Independence, Kans
Motorcycle: 1980 Honda GL1100 standard

Re: mysterious vacuum line:

Post by mud/dauber »

Thanks Denver for checking on that for me.

MD
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virgilmobile
Posts: 9101
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: mysterious vacuum line:

Post by virgilmobile »

I don't have mine anymore but I don't recall a t there either.
Keep in mind that there is no vacuum on that line at a idle.It only has vacuume as the engine rpm increases and its not much.I think it maxes out about 8"
mud/dauber
Posts: 10
Joined: Sun Aug 13, 2017 12:19 pm
Location: Independence, Kans
Motorcycle: 1980 Honda GL1100 standard

Re: mysterious vacuum line:

Post by mud/dauber »

So, I'm considering just removing that extra line and putting in with a box of misc parts so not to lose it just in case. It has not affected anything nearest i can tell. I'll just run a direct hose line from no. 3 carb niplet to the auto spark advance diaphragm. All in favor say "aye"; opposed say "nay".

Thanks Virgil

Muddy
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virgilmobile
Posts: 9101
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: mysterious vacuum line:

Post by virgilmobile »

Aye...eye..captain..
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Rc67
Posts: 80
Joined: Sun May 20, 2018 6:26 pm
Location: Jackson, ms
Motorcycle: 1980 GL1100I

Re: mysterious vacuum line:

Post by Rc67 »

mud/dauber wrote: Mon Aug 14, 2017 10:40 am Maybe. I am going to check to see if mine is clogged because very little air can move through it when I draw or blow in the end of it. If anyone out there has a 1980 standard gl1100, I wish they would see if they have the same set up from the carb to the advance diaphragm. See if there is a "T" junction and tell me (us) where that spur line goes to.
I realize I’m writing to an older topic but I have an gl1100 that has the exact configuration as your description. Did taking the T off and going straight to the #3 carb make a difference? If so, I will do the same as I can’t find a connection for this phantom vacuum line either.
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DenverWinger
Posts: 1934
Joined: Thu Jun 23, 2011 2:20 pm
Location: Denver, CO
Motorcycle: (s)
1980 GL1100 STD Vetter (2005-)
1993 GL1500 Aspencade (2017-)
1983 Trav-Lite Camper (2010-)
Past rides
1972 CL350 (1980-1988) sold
1978 Suzuki GS550 (1985-2005) sold
1977 GL1000 (2002-2006) sold

Re: mysterious vacuum line:

Post by DenverWinger »

Only use for the tee I can think of is if somebody was using it for a gauge, otherwise the spur should be plugged.
♫ 99 Little Bugs in the Code, ♪
♪ 99 Bugs in the Code. ♫ :(
♫ Take one down, Patch it around, ♪
♫ 127 Little Bugs in the Code. ♫ ♪ :shock:

~Mark
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Rc67
Posts: 80
Joined: Sun May 20, 2018 6:26 pm
Location: Jackson, ms
Motorcycle: 1980 GL1100I

Re: mysterious vacuum line:

Post by Rc67 »

DenverWinger wrote: Tue Oct 23, 2018 11:53 pm Only use for the tee I can think of is if somebody was using it for a gauge, otherwise the spur should be plugged.
Thanks, I will get that lined plugged up then...


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