LinkBack Thread Tools
post #1 of 9 (permalink) Old 05-31-2013, 09:38 AM Thread Starter
ctrobins's Avatar
Join Date: Mar 2013
Location: Novato, CA
Year: 84
Make: Honda
Model: 84 Aspencade
Posts: 38
GL1200: High RPM when hot / or clogged (?)

Hi Guys,

I'm hoping someone has some experience, or can tell me what they think is going on with my bike.

I have an 84 GL1200 Aspy. A couple of times I've experienced this condition, then it seemed to clear up by itself.
The 'condition' is that after some time at sustained speed / RPM's (like 70 and 3,400). Then I'll get into town where I'll just be at more like 15-25 MPH and 2,200 RPM (approx)... The bike will be stuck revving at 3,000 or higher! Even at idle the RPM's won't come down. The latest occurrence (yesterday)... this happened, but it seemed ALSO to be influenced by the engine temperature... The bike was running very hot after a lot of slow twisties on a hot day and getting stuck in a bit of stop-n-go traffic. When the bike got hotter, the idle RPM got to about 4,000.
I managed to get home safely and park the bike.. by this time the bike would idle at 'only' 2,400 RPM... which I saw as an improvement. Later, I started the bike up... and thankfully it was idling normally (about 1,000 rpm)... But, I didn't do anything to fix it. Which is why I think the temp had an influence.

I suspect the issue is something to do with the fuel system... maybe a chunk of debris is blocking or holding something in the wrong place... But, could it be an electrical thing?

I know it wasn't the throttle cable or linkage... I was able to see and feel that all that was moving normally.
I know it wasn't the choke cable or linkage... I could see those components working normally as well.

I did rebuild the carbs recently, and USUALLY the bike runs very well and reliably.
There IS some debris in my gas tank still (rust granules) and I do clean my bronze fuel filter every few gallons. (which is why I suspect something is getting lodged in the carb causing the revving).

This type of thing has happened before, and I attributed it to debris in the carb. And it seemed to clear itself... But, this is the first time engine temperature seemed to play a role.

So... does anybody have any idea of what could be happening with my bike?


Craig - Novato, CA
ctrobins is offline  
Sponsored Links
post #2 of 9 (permalink) Old 05-31-2013, 11:07 AM
The Irish Crew
Heffo's Avatar
Join Date: Jul 2004
Location: Dublin, Ireland
Posts: 1,248
Check for vacuum leaks first, as they can cause erratic idle and other problems.

Dave Heffernan.
Heffo is offline  
post #3 of 9 (permalink) Old 05-31-2013, 11:21 AM
Senior Member
Ansimp's Avatar
Join Date: Jan 2013
Location: Brisbane Au
Model: 1981 1100
Posts: 1,230
Does sound more like throttle is not returning properly
Ansimp is offline  
post #4 of 9 (permalink) Old 05-31-2013, 01:18 PM
It aint rocket science
DriverRider's Avatar
Join Date: Nov 2010
Location: Glastonbury, Connecticut, USA
Model: The best
Posts: 3,620
Not familiar with the 1200 but generally speaking if the throttle plates WERE returning to idle position no way the engine could get enough air AND fuel to support a 4k RPM. Your throttle plates would not be affected by junk in the fuel line or tank. The junk in the fuel theory would have to effect all 4 carbs at the same time, if one carb were plugging something it wouldn't pull the other 3 up with it IMO.

The air AND fuel required for a 4k RPM must be coming from a different carb circuit. If you have enrichment rods for a choke system I would be looking there.

As a test with engine warm crank up the choke and see if you can simulate the fast RPM. There could be other systems in the engine which will increase RPM if an overheat is detected which I would not know about and might include a change in Ign timing also.


There is NO substitute for experience
I'll be around when I come around and not before

Starter ride
Previous rides
Yamaha 360
Yamaha 650
WS Grand Chapter CT
If local and need help with a 1500, Valkyrie or ST repair feel free to PM
DriverRider is offline  
post #5 of 9 (permalink) Old 05-31-2013, 02:49 PM
Join Date: Sep 2010
Location: Horn Lake, Mississippi, USA
Posts: 271
Wild Guess

This is just a guess, since I wasn't there playing with your bike when the high rpm idling condition was there. Next time it starts acting up like that, open up your faux tank and a) Fan it with a notebook or anything you have handy. b) Unscrew and screw back in the gas cap without necessarily removing it.

A while ago when my starter was acting up -only while hot- I stop and fueled up with the engine running. When the gas fumes were pulled by the engine, (air inlet is right there) the rpms went up, but went back to normal when I put the cap back on.

Good luck sorting this out, please let us know what it was when you sort it out.
Bufallowing is offline  
post #6 of 9 (permalink) Old 05-31-2013, 03:13 PM Thread Starter
ctrobins's Avatar
Join Date: Mar 2013
Location: Novato, CA
Year: 84
Make: Honda
Model: 84 Aspencade
Posts: 38
Thanks for the tips!

As of this morning my bike is idling/running completely normal.. and I haven't done anything.

I did try the 'choke' test.. and YES. I can get it to rev up and emulate the problem I had... So, maybe the linkage to the plungers is not working all the time.

The throttle cables and linkage do/did seem to operate smoothly, and it was easy to see the linkage working... the choke rods are a bit more buried and I didn't look at the left bank of choke plungers... so maybe they were the culprit.

Since this problem is intermittent It may be some time before it happens again.. But, when it does... I'll check the items you've mentioned and post any updates.

Thanks for your input!

Craig - Novato, CA
ctrobins is offline  
post #7 of 9 (permalink) Old 06-07-2013, 04:53 PM Thread Starter
ctrobins's Avatar
Join Date: Mar 2013
Location: Novato, CA
Year: 84
Make: Honda
Model: 84 Aspencade
Posts: 38
6/7/13 Update

The problem 'seems' to have cleared up. But, I'm not really sure what is different now. Here are a couple of things I did do that may have fixed my Revving (or slow to return to idle) condition.

1) The idle was set a little high (about 1,400 rpm). I adjusted it to be more like 1,000
2) I removed and re-inserted 2 of the carb sliders. (the ones that are easy to get to.) They seemed to be fine. the needles are clean and the slides moved freely.
3) Adjusted the throttle cable. After adjusting the idle screw I noticed the throttle didn't have any play at all. So I loosened it up a bit so that there is just a little play in twisting the grip.

Another thing that may have affected this was that In a recent tank, I added about 5 ounces of SeaFoam to the full tank. I believe the SeaFoam is pretty much out of the system now.

If the condition arises again, I'll be back with either more questions, or more solutions!

Craig - Novato, CA
ctrobins is offline  
post #8 of 9 (permalink) Old 06-07-2013, 05:08 PM
Senior Member
Cornpone's Avatar
Join Date: Feb 2013
Location: Minnesota
Model: 1995 GL1500 Aspencade, 1985 GL1200 Aspencade, 1983 GL1100 Standard with Vetter Windjammer fairing.
Posts: 860

The key fact was the high temp, to me, since it makes things expand. This will sound weird, but sometimes when we pull, rebuild, and re-install carbs they need to "set-in" themselves. Things that are a bit too close spread out with heat and things that aren't perfectly sealed work themselves into perfection. I've had it happen many times and never had it re-occur. Hope that's your experience!

Cornpone is offline  
post #9 of 9 (permalink) Old 06-08-2013, 10:01 AM
Senior Member
tire joe's Avatar
Join Date: Jul 2007
Location: Cave City, Kentucky, USA
Model: 1985 i
Posts: 771
Got to have a little slack in throttle cable, vacuum leak when hot can give a higher idle,

I want ride Tire Joe
tire joe is offline  
Closed Thread

  Steve Saunders Goldwing Forums > Forums > Goldwing Technical Forum

Quick Reply

Register Now

In order to be able to post messages on the Steve Saunders Goldwing Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Forum Replies Last Post
High idle when hot, GL1200 hightiger Goldwing Technical Forum 12 03-21-2015 01:56 AM
GL1200 Rough low RPM's High RPM's fine...fuel filter? bigfatman4644 Goldwing Technical Forum 10 04-03-2013 01:26 PM
High RPM at 70 MPH BenHasAGL1100 Goldwing Technical Forum 6 08-06-2008 09:29 PM
High RPM Break up thessler Goldwing Technical Forum 32 01-17-2008 05:36 PM
High RPM and hot weather = high temp readings Ghost Rider 2 Goldwing Technical Forum 16 11-20-2007 06:27 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome