Odd RPM Problem

[Seive]

I'm having a small problem with the carbs on my 1983 GS550L. I've taken the carbs off four times now. I've cleaned, and cleaned, and cleaned the jets. The bike runs smooth save one little "feature." When it's on the kickstand the RPMs are much lower. When I life the bike up to riding position, my RPMs will SHOOT through the roof even with the throttle completely closed.

I'm kinda at my wits end. I've adjusted the cable and the idle screw all the way out and this is still happening. I've triple checked my float levels and needles/seats.

Any ideas? I'm thinking it might be my air mixture screws. I think that's what they're called. I've got four of them at the engine side of the carbs on top I can adjust. Do you think they're too far out? I had them out two and then three turns each. I can take pictures if I need to.

[Steve]

You have cleand the jets, have you cleaned the carbs, too?

There are tiny little passages between the jets that need to be cleaned, too. Recommended procedure is to totally dismantle the carbs, soak the bodies in Berryman's Carb Cleaner Dip for several (up to 24) hours, then re-assemble, using new o-rings from cycleorings.com.

While you are at the cycleorings site, be sure to also get the intake boot o-rings and stainless hardware, if your bike uses them.

Also be sure to set your floats to the proper height, as that can affect operation at an angle.

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[JimmyR]

Maybe the throttle cable is catching on something?

[Nessism]

While you are at the cycleorings site, be sure to also get the intake boot o-rings and stainless hardware, if your bike uses them.


.

This........

BTW, please see the carb rebuild tutorial and Newbie mistakes thread linked in my signature. Short cut are long cuts when it comes to motorcycle maintenance...

[Seive]

Money is very tight right now while my wife is looking for a job, but I'm planning on buying a carb rebuild kit very soon as well as dipping them. I understand the importance of doing it right the first time! Right now I'm just trying to get the bike to run halfway right until I can order everything so I can get around. I'll tinker with it when I get off work.

Thanks!

[BassCliff]

Greetings and Salutations!!

Hi Mr. Sieve,

Is the airbox and air filter installed?

Don't waste your money on "carb rebuild kits". They usually don't have all the parts you need and are of inferior quality anyway. Just re-used all the metal parts (jets) after dis-assembly and dipping. Then replace all of the internal O-rings with a kit from cycleorings.com. It's all in the links below, and in the links provided by Mr. Nessism.

Let me dump a TON of information on you and share some GS lovin'.

I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", "Top 15 Tips For GS Happiness", the Carb Cleanup Series, and the Stator Papers. All of these tasks must be addressed in order to have a safe, reliable machine. This is what NOT to do: Top 10 Newbie Mistakes. Now let me roll out the welcome mat for you...



Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[Seive]

I've got it fixed to a point that the bike runs fine save idling. I can keep it running with the throttle barely twisted and my hanging idle has all but disappeared.

The plugs were coming out VERY lean, so I readjusted my floats and sprayed starter fluid around my airbox boots to check for leaks... and found one. The clamp was apparently broke in half but still hanging on and the bottom of the airbox where the boot connects was bent straight up so there was a gap. I took some pliers and straightened that out, and bought a large hose clamp (bent it to the shape of the boot) and clamped that puppy down. No more leak.

I'm going to ride it a bit and check my plugs again JUST to double check and make sure I'm not running too rich or lean. About how long should I do so before checking my plugs again?

Also, I checked the throttle cable and it's not hanging in any way. I tried doing like you suggested and rocking the bike. Since I adjusted my floats to allow in more fuel the bikes not trying to stall anymore when leaning or standing up straight.

I think short of fully disassembling the carbs and dipping them this is probably about the best I'll be able to get it running, so that's the next thing on my list. I'll avoid a rebuild kit like posted and just go with an o-ring set. Also, the idle jets inside the carbs are stripped horribly (partly my doing, mostly from the PO.) as well as half the screws for the float bowl and the diaphragm cover. I was able to get them to tighten back down, but I'd like to replace them. Where can I grab those?

Thanks a ton for all of your help guys. I'm really enjoying the bike so far and hopefully I'll be able to for a long time to come.