GS550ES - Carb Issues

[Jet-Lee]

I'm only a noob to these bikes, not bikes in general. This is a 1986 GS550ES (the DMV says that according to VIN, it's an ESG, I dunno what the G is) with stock airbox (stock-looking filter), Yoshimura 4-1 header and can.

So I got it to start last night, it fired right up, but I've uncovered some more issues.

Obviously I need to rebuild these carbs, not an issue. However, what's a good resource for any new seals/jets that may be needed? I'll want o-rings at the minimum. What are the stock jet sizes and what's recommended for the Yoshimura? I want to get it running right, as it sits now, before considering any other modifications.

I didn't have any information on the idle mix screw setting, so I went with my CV-40 knowledge and set 2,3 and 4 at 2.5 turns out from bottom. I've since read that 1.5 turns is the magic number.

Now cylinder 1...the idle mix screw is jammed in there. I was thinking of using a bolt extractor to get it out since the flathead has been stripped. Other ideas? Source for new screw?

The PO pulled off the boot for the chokes and attached wires directly to the plunger itself. This makes it a pain in the ass to work with since it's a huge vacuum leak at this point. What am I looking for, for a choke cable? I fear I will also need new plungers. In the meantime, would it be unreasonable to bottom out the plungers and seal off the passage with sealant, effectively removing the choke all together for now, until I can get the correct parts?

Thank you in advance!

-EDIT-

Stumbled across a reference to Z1 Enterprises...currently looking there for anything I [may] need.

-EDIT-

What Mikuni model carbs are these?? BSW30SS?
Everything I'm finding is referencing 4 individual carbs, mine has the two doubles.

-EDIT-
I'm confusing myself now. This thread says 3.5 turns out for the idle mix. Hmm...thinking I do need to seal off that choke and just play with it.

[spyug]

Ok for O-rings Robert Barr on here is your man. He runs www.cycleorings.com and is a hell of a human being don't forget to get the big O-rings for the carb intake boots. Air infiltration here is often a problem when rings dry out and shrink or split and you can drive yourself bonkers trying to figure why you lovely clean and newly rebuilt carbs don't run right.

Now for air mixture screws 2.5 out always worked best for me. Start there.

As far as the choke situation I think you will have issues. The GSs (pretty near all of them) are cold blooded even in summer and an enricher circuit (choke) is usually needed. Its going to be difficult to start and run right if things are not in their correct position.

You could try bottoming out the plungers and blocking the passage but I think that will create more problems for you. Best solution would be to get some new choke cables with the plungers and passage caps. Now there are quite a few guys on here that have these bikes so someone must have them. Put an add in the parts wanted section. They should also still be available from Suzuki but likely will be costly.

I had a parts bike which I traded along with my pristine 550. I will see if I can approach the guy and see if he still has the parts.

As far as jetting don't worry about that until you have the carbs sorted, synched, starting and idling right.

PS I just check an online parts fische and the plungers, caps, springs and O-rings are all sold individually so if your cables are good just get the bits you need. I couldn't get prices from the fische so trot off to your locally Suzuki shop and check.

[Jet-Lee]

Thanks!

Sealing the choke would not be a permanent solution by any means, just so I can move on to the next step until I get the correct choke parts ordered and delivered.

One of my Buell's is cold blooded, ran it for a year without choke, that was fun in the mornings. I'm not new to it, don't want to do it, but I hate sitting around waiting for stuff as well. I want to be productive.

Ideas on the idle mix screw for cyl 1?

[spyug]

I understand. Do what you have to do.

As far as the stuck screw, that is a biotch. I have never had any luck getting them out myself.

The only thing I can think of would be to try an "easy out" or left hand drill bit if you can get one small enough. On some carbs you can cut away the tunnel in the carb body to expose the head of the screw. Once you reach the head, you can then cut a new slot with a dremel tool. I can't envisage the setup on these carbs so I can't recall if that would work.

If you can get an easy out or drill into the head but some heat and penetrating fluid to it before trying the extraction. Hopefully that would break it free.

Once you do get it out and replace it I would recommend a dab of antiseize on the threads as you put the screws back in.

Sorry I can't offer anymore help and good luck with it.

[Jet-Lee]

I didn't think about cutting the tube down to dremel the screw. It's completely do-able on these carbs.

I'm not finding any seals specific to these dang BSW30SS carbs...

[spyug]

I'm not finding any seals

Clarify please. What seals exactly?

[Jet-Lee]

Clarify please. What seals exactly?

Unless those in your link also work for the BSW dual-throat carbs ... all.

With something this old, if it comes apart, it gets a new o-ring/gasket/seal when it gets put back together.

[spyug]

You mean O-rings? Robert's standard o-ring set will work fine for those carbs. Nothing special required. Don't forget the carb intake boot O-rings as I mentioned before.

[Jet-Lee]

You mean O-rings? Robert's standard o-ring set will work fine for those carbs. Nothing special required. Don't forget the carb intake boot O-rings as I mentioned before.

Oki Doki. Ordered the whole shebang. Thanks!

Will post more when I get more work done. I'm on an every-other-day schedule right now.

[Jet-Lee]

While waiting for everything to get here, I pulled the carbs and cleaned everything. The slides were stuck up top, all of them. The idle speed was bottomed out. It was just dirty and bad.

Well I got everything sprayed through with lots of carb cleaner very nicely. It's all shiny now. The problem is...it doesn't even start now.

So, I read that someone else had similar issues and the ultimate result was valves being out of adjustment. So...looking for a how-to for that while I wait for new o-rings and choke cables to come in for the carbs.

If anyone has any other ideas, let me know.

I set the idle mix screws at 2.5 turns from bottom. I couldn't read the jets to know size they are. I may just pull the carbs again and let them soak in some dip for a few hours. Also going to drain the fuel and use new, should've done that from the beginning, but it looked and smelled fine. How do I get this damn airbox out of here???

[GSX1000E]

To answer your question, remove the exhaust, remove the engine mounts and move the engine forward and have at it. It is actually even easier if you remove the engine.

[Jet-Lee]

Oh joy, so it's not one of those in-the-frame jobs. *sigh* I was afraid of that.

Specs for gap? I've read some people saying max of .1mm and Google said .003" (.075mm) max.

To buy shim kit before or after? Would be a waste of money if the valves are fine...hmm...

[spyug]

No need to pull the engine it definitely can be done in the frame. The valves are not shim and bucket either so no shims to be bought. Pull up the manual on Cliff's site and have a look at the procedure. It's not difficult. Sorry but I don't recall the clearances but it is in the manual.

As far as the carbs, there is no way to get them properly clean unless they are dipped in carb cleaner. A shot of spray just will not do it. You are just frustrating yourself.

The GSs are notorious for having difficult to deal with airboxes and all you can really do is move the battery box out and push the airbox as far back as it will go. There really is no other way.

Getting back to the carbs, I would wait until your O-rings turn up. Give the carbs a good 24 hour dip, rebuild and try again.

[gustovh]

Thanks!

Sealing the choke would not be a permanent solution by any means, just so I can move on to the next step until I get the correct choke parts ordered and delivered.

One of my Buell's is cold blooded, ran it for a year without choke, that was fun in the mornings. I'm not new to it, don't want to do it, but I hate sitting around waiting for stuff as well. I want to be productive.

Ideas on the idle mix screw for cyl 1?

Use heat on the carb body, I used a small propane rosebud, put pressure to turn the screw out as you are heating the carb body and stop with the heat when the screw releases. Should not take more than 60 seconds.\
V

[Jet-Lee]

Thanks guys!

I forgot that I downloaded the manual. Geez...I always refer Buell guys to the well-written manuals, then here I am not using this one. facepalm