1985 GL1200 Carb. Rebuild - Printable Version

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1985 GL1200 Carb. Rebuild - Guest - 08-26-2007

Let me begin with saying this is the First GL1200 Carb. rebuild that I have done.

My carbs are now back on the bike and have around 800 miles on them without a single problem at all.

I will also add that the GL 1200 Carbs are much easier to work with than the GL 1000 carbs.

Many have made Carb. rebuilding sound like rocket science, Its nothing of the sort,
Anyone with any mechanical ability can do this, patience is required as is attention to detail, and clenliness.

This Is not a 100% rebuild, as my problems were isolated to 1 spot but I will try my best to touch on all points for a complete rebuild.

First, I would suggest that you have your new carb kits in hand before starting this project, should you disassemble your carbs, and wait a week or so to put them back together, you would be suprised how easy it is to loose the small parts and forget how things came apart.

Prepare an area for this job no less than 4'X4' .
This area must be very clean as a particle the size of a grain of salt will restrict some of the passages in the carbs.

Tools needed:
Fire extinguisher, you can never be too careful!!!!
4 small Tupperware containers, 4"X4" or so.
Phillipps screwdriver.
10mm socket ratchet and extensions.
Flat screwdriver.
Small air compressor if avalible.

2 cans of spray carb. cleaner.
several clean dry lint free wrags.

1st Things 1st, Before you begin remove anything from your work area that could ignite the gasoline you will encounter.

Label your containers 1,2,3,&4.
as you disassemble each carb put the parts from that carb in the proper container. do not mix the parts between the carbs!!!!!

You will be using Carb cleaner and compressed air, Use the proper protection, ie. safety glasses, all the carbs in the world are not worth the loss of an eye.

Start by removing the Lower fairings, the filler panels and the plug covers.
label and remove the plug wires.

I personally removed the side covers and the false tank.

First lets remove the Air Cleaner.
The fuse block is just snapped in, lift it up and set it aside.
Remove the wing nut and fuse block bracket.
Remove the aircleaner lid
[Image: SD530802-copy.jpg]

Next, remove the 4 phillipps screws at the bottom of the air cleaner, they are the ones shown at the bottom left and right of the picture, there are 2 more at the front end of the air cleaner housing.
Then remove the Stud mount that holds the top on, 2 screws
[Image: SD530803-copy.jpg]

Drain the fuel from the bowls.

Now for the intake to head bolts,
Remove 8 Bolts
At the top end of the intake runner (Top Center Left) there is a rubber boot that attaches the intake to the manifold box, it is held by a clamp, back out the phillipps screw holding the clamp and gently remove the intake runner, all 4 of them.

[Image: rebuild1-copy.jpg]

Carefully pry the air tubes out of the head.
Check the hoses for loose connections, damage or detioration.
Tighten any loose connections, and or replace any damaged hoses.
[Image: 3-copy.jpg]

Remove the fuel pump to plenum Line.
I suggest replacing all fuel lines, Filter and clamps.
[Image: rebuild2-copy.jpg]

At this point you can shift the assembly Left or right to easier access the remaining connections.
back off the Nuts on the throttle cables, and remove the cables from the linkage
[Image: SD530805-copy.jpg]
[Image: SD530806-copy.jpg]

Next, remove the choke cable, small phillipps screw that holds the cable then roll the cable around to the rear to release it.

[Image: SD530808-copy.jpg]

Carefully remove the Carb assembly from the engine.
Cover all openings to the engine, if one small washer nut ect. drops into the intake opening unnoticed and the engine is reassembled and operated, it will Destroy that cylinder.
Be careful that nothing is allowed to fall into the openings.

[Image: SD530807-copy.jpg]

Remove all 4 carb tops, springs and pistons, clean inspect and Place each carbs parts in the box for that carb, do not mix the parts.

[Image: SD530785-copy.jpg]

Flip the assembly over and remove all 4 bowls.
[Image: SD530775-copy.jpg]

Remove 4 Floats, needle valves and valve seats.
Clean valves and seats, place them in your carb parts boxes.

[Image: SD530779-copy.jpg]
Remove the main jet and slow jet, Clean out with carb cleaner and compressed air.
You can blow through them to be sure they are open, aslo if you look closely you can also see through the jets.
[Image: SD530782-copy.jpg]

More to come!!!!!!!

- William_86 - 08-26-2007

Please post more pics if you have they will be very helpfull for me and everyone else!!

stay safe.

- Guest - 08-26-2007

This is an ongoing post, I will be adding to it untill it is finished.
It will all be contained in the original post as I will be using the edit feature.


- admin - 08-27-2007

Excellent Jim, thanks for taking the time to share this with us and I'm glad that the rebuild made a difference in how your bike runs.

Did you find anything specifically wrong inside the carbs? :?:

- Guest - 08-27-2007

Its my Pleasure.

Yes I did Vic, The emulshion tube in #3 was totaly restricted, It was wedged in or something, 120lbs of air pressure would not even move it.
I finally found a strand of copper wire about the size of 4 hairs, LOL
and used it to dislodge the blockage,
The pros say dont do the wire thing, as it may scar or enlarge the passage.

I used a high power loupe to inspect the tube and it looked great.


- William_86 - 08-27-2007

Okie dokie thanks a lot plz take pics of everything ;p

- billzamp - 10-01-2007

Hi Jim - It's been a while since I asked you to post the GL1200 carb rebuild pics. I was away for a period but I am back and I really appreciate your documented efforts. Great stuff!

I have been pumping Carb Cleaner through the fuel in my 86 Goldwing Aspy and letting it sit in the float bowls, hoping to clean up any bad fuel clogging the jets and then I started to pump Techron concentrate through the fuel to clean up any carbon build-up and valve fouling. I drove the bike a fair amount at highway speeds for a few weeks and the carbs have cleared themselves enough to idle roughly with just a little choke applied. The carbs definitely need to be cleaned and rebuilt properly and I will take on the task shortly. I did pull the vacuum slide covers while on the bike and found one slide valve crimped and damaged. I pulled an old one from another carb set I had and it worked fine. Your documented efforts are great and you made some great suggestions on what to watch out for and how to prepare for and avoid pitfalls. I appreciated your words of wisdom on how to approach the rebuild.

I have to admit, I would not have tried the copper wire to clean a carb passage ... too great a potential for irrepairable damage :!: I'm glad it worked out for you! You never mentioned if you used an aftermarket GL1200 carb rebuild kit or just purchased select Honda parts, jets, needle valves, seats, seals and etc., as needed. Any other pearls of wisdom since you have had some time to reflect and think about the process and the positive results?

Thanks for all your efforts. I think many old Goldwing owners will be benefitting from your experience and documentation efforts for some time. Idea Ride on ... Bill

- Guest - 10-01-2007

Thank you Bill for your comments.
I still have much more to post in this thread before it is finished.

As far as the Copper wire goes, it was either do that or replace the tube.
So I elected to ram it out.

Copper wire the size of 4 hairs, in a hardened brass tube, not much chance for damage,
The gaskets and seals are genuine Honda, but the kits from Sirius in Kitchner are great.

As far as the hard parts inside the carbs, I in all my years of mechanicing have never changed any of them out unless they are damaged or corroded, they can be cleaned and restored to like new in most every case.

I will finish the thread as soon as I can....


- William_86 - 11-20-2007

Hi there Jim, hows it going have you finished ur project??? i'd love to see this post finished Smile

GL1200A Carb Rebuild. - billzamp - 12-10-2007

Hi Jim - I am finally getting around to rebuild my carbs on my 86 Aspy GL1200. I checked your posting to see if you have been able to complete your documented GL1200 carb rebuild process but it looks like you have been busy with other things.

Randakk has finally completed his GL1200 carb rebuild kits - they are now available on Ebay for $99.95 for the four carb set and it looks like a quality kit. I am considering getting these soon.

Seems both you and Randakk suggest that the needle valves and seats are usually cleanable and do not necessarily need to be replaced. He suggests that it is worth getting the OEM Honda parts if they need replacement since they will be closer to spec than any typical aftermarket kit.

I have been looking to find new OEM Honda woven-covered fuel hose but I haven't located it yet. The dimension on typical automotive fuel hose seems too large and it doesn't fit tightly. I am planning to start this project right after Christmas. If you have the opportunity to complete your documented carb rebuild I would really appreciate it. I know it is a busy time of year so I will understand if it isn't possible now. Thanks, Bill

- William_86 - 12-10-2007

please Jim we all are waiting for this :lol: :lol: :lol:

now with Randak's Kit i bet many will be doing the carbs Tongue

carb rebuild - redwing1984 - 12-11-2007

I'm doing my carbs in March or April, and the service tech, told me while I have the carbs out, I should also replace the O-rings for the cooling system, since taking the carbs out the O-rings more then likely will crack or brake from deterioration.
Did you do that, and if not were the O-rings still in good shape?

- Guest - 12-11-2007

I replaced the manifold o rings, but not the cooling system o rings.

- William_86 - 12-12-2007

on the 1200 is not needed to remove any part of the cooling system right?

- Guest - 12-12-2007

Not at all.