Erratic Surging


Information and questions on GL1500 Goldwings (1988-2000)
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bohdan
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Erratic Surging

Postby bohdan » Fri Aug 30, 2013 7:07 am



Greetings Folks. Perhaps somebody had a similar problem. My 93A rides like a charm. However, it developed a new problem. Upon deceleration, the RPM's will go down to maybe 300-400, then slowly creep back up to the 750-800 range. Only once it stalled upon coming to a stop sign. It was also raining at the time. It appears that it may be a vacuum line, but do these symptoms indicate a particular one? Have a Great Day!!



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virgilmobile
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Re: Erratic Surging

Postby virgilmobile » Fri Aug 30, 2013 7:26 am

It does sound like a vacuum leak....One in particular.??
Well there seems to be a problem area where any vacuum hose makes a sharp 90* bend...
On my 88, I found 7 of them.One split into a pinhole,the rest would soon follow.
I opted to just replace every suspected hose...It took all day but now I'm confident it won't happen again...
By the way..There is one under the rubber mat that is under the carbs..It can only be replaced by removing the carb assembly.
There were 2 on the left and 1 on the right intake runner.One inside the right frame by the carbs.
1 under the mat and 2 on the carbs.
Here's a few pictures to gaze at too....
Don't dismiss the possible obvious either.. :mrgreen:

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bohdan
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Re: Erratic Surging

Postby bohdan » Mon Sep 02, 2013 8:21 pm

Thank Virgilmobile I will have to keep day available

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redial
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Re: Erratic Surging

Postby redial » Tue Sep 03, 2013 2:48 am

Are all the vacuum hoses the same size? Can you just get a metre or two, and cut them to length? Is two metres enough? (about 6ft 6 ins).
Len in Kapunda

The world is not going to finish today, as it is already tomorrow in Australia and New Zealand, and other islands of foreign nations such as Guam and Samoa.

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bohdan
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Re: Erratic Surging

Postby bohdan » Tue Sep 03, 2013 7:01 am

Hey Virgilmobile. Another dumb question, with exception of the vacuum hose underneath the mat, how much of the bike has to come apart?

P.S. Is that your bike with the acorns? Amazing that it can get into there.

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virgilmobile
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Re: Erratic Surging

Postby virgilmobile » Tue Sep 03, 2013 7:29 am

Fortunatly not mine but it does happen.We metal screen the intake port of the air chamber.
As far as the hose size.I removed a sample and hooked it down to the local store.they matched and I bought 6' of each size.
The seat,top shelter,side covers,lower faring all come off.
You'll need a 18" Phillips and a 16" needle nose.
Drain the radiator.2 hoses hook to the bottom of the carb.

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redial
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Re: Erratic Surging

Postby redial » Wed Sep 04, 2013 11:10 pm

Thanks for that. Is that a true Phillips screwdriver or a JIS?

Talking about JIS, I attempted to have one sent to this foreign country, and they refused to send it: "Because of trade department restrictions" I wrote to your US Trade Officer, never got a response, and mentioned that if Oz is good enough to have a free trade agreement, then surely screwdrivers should be good enough to send to us? What a moron, the seller, not the US Trade Officer!!!
Len in Kapunda

The world is not going to finish today, as it is already tomorrow in Australia and New Zealand, and other islands of foreign nations such as Guam and Samoa.

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Re: Erratic Surging

Postby virgilmobile » Thu Sep 05, 2013 6:45 am

Just a plane old #2.there are 2 clamps that hold the carbs to the intake.There accessed from each side.way up in.youll need a flashlight to see them.

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bohdan
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Re: Erratic Surging

Postby bohdan » Thu Sep 05, 2013 7:10 am

Is that bend a pre-molded rubber hose? Hard to see in the pix. Have a great day!!

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virgilmobile
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Re: Erratic Surging

Postby virgilmobile » Thu Sep 05, 2013 8:54 am

Yea.Ill try to round up some pictures and post them this afternoon.

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Re: Erratic Surging

Postby virgilmobile » Thu Sep 05, 2013 3:10 pm

Here's my first post about removing the carbs on my 88...viewtopic.php?f=6&t=10504

Here's some pictures from Google and the manual for a overview...


Replacing bad vacuum lines is not a morning job...Expect all day...at least....I took over 4 hours on my first attempt to just get the carbs out....I can do it now in 2.5 hours....

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Re: Erratic Surging

Postby virgilmobile » Thu Sep 05, 2013 3:22 pm

If your at all mechanically inclined,it's not a difficult job....just very time consuming....Lots of stuff to remove to get the carbs pried out....Plenty of hard to reach hoses,vent pipes,cables,vacuum lines and let's not forget the amount of plastic.

I do mean pried out too....ya gotta get a tight grip on the front lip and pry up and back to get them to release from the rubber couplers,both at the same time...Putting them back is just as hard...A bit of lube and a lot of down pressure to get them seated again....
All while balancing on the frame where the seat was....

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Re: Erratic Surging

Postby WingAdmin » Thu Sep 05, 2013 3:34 pm

virgilmobile wrote:If your at all mechanically inclined,it's not a difficult job....just very time consuming....Lots of stuff to remove to get the carbs pried out....Plenty of hard to reach hoses,vent pipes,cables,vacuum lines and let's not forget the amount of plastic.

I do mean pried out too....ya gotta get a tight grip on the front lip and pry up and back to get them to release from the rubber couplers,both at the same time...Putting them back is just as hard...A bit of lube and a lot of down pressure to get them seated again....
All while balancing on the frame where the seat was....


Those rubber couplers get hard and leaky with heat and age. When I had my wife's bike apart this winter, I finally gave up trying to get them together and leak-free, and ordered a replacement set from Honda. The new ones were soft and super easy to put on.

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Re: Erratic Surging

Postby virgilmobile » Thu Sep 05, 2013 3:45 pm

That's a fact.Its a determination one makes at the time of inspection.
That's why I say "it takes time" to do this job.
Seems there is always a 'got ya' somewhere.

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bohdan
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Re: Erratic Surging

Postby bohdan » Fri Sep 06, 2013 7:09 am

Thanks virginmobile. Great pix and advice. Now I have a better understanding of how to attack. Just hope that I don't have to pull the engine....lol Bike runs wonderfully minus the issue at hand. Just need to get that full day to do this. thanks again.

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Re: Erratic Surging

Postby virgilmobile » Fri Sep 06, 2013 7:20 am

If you need more help,just ask.I got a ate of needle nose at harbor freight.There about 16" long and slightly angled at the end.Really necessary to reach behind the carbs to get the cooling lines off.
I also took pictures while I worked on it so I had a reference for reassembly.
A silver marker pen to mark hoses helped.




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