Gs550 jetting issue

[rslade274]

Hello, I've recently bought a 1982 Suzuki gs 550l
without knowing how problematic it would be, I ditched the air box and bought pods, also cut a stock exhaust system's baffle/mufflers and welded shortys on.
So here is my question:
With running pods and shorty mufflers with stock headers, where should I start with jet sizes, float bowl heights, misc. info, etc etc?? I already understand it may not run 100% even when tuned properly with this set-up.

The bike originally came with old rusty 4-1 aftermarket exhaust I threw away and the stock airbox. size #100 jets, and it ran okay but wouldn't go above 5000 rpm, fyi. I expect the bike was jetted by the PO for the 4-1 exhaust.

What jet sizes should I try, or drill bit sizes to drill out the stock ones?
Any info would be awesome, thanks

[Steve]

What jet sizes should I try, or drill bit sizes to drill out the stock ones?
Any info would be awesome, thanks

The only information that I can safely offer you is to NOT drill out your jets.

After drilling out your jets, you will be left with brass pieces of unknown quality and size.
You will have NO idea how they compare with known jet sizes.
You will still be in the dark as to how to jet your carbs.

Stick to known jet sizes from Mikuni.

.

[BassCliff]

Greetings and Salutations!!

Hi Mr. rslade274,

It's always best to start with a baseline (stock), get that running well, and then modify from there. But I guess we're past that now. With your setup you will have to do some plug chops to verify the jetting and re-jet if necessary. Any intake or exhaust modification will require re-jetting. Usually the easiest route is to purchase a Dynojet Stage 3 kit. Or you could buy bigger mains (4 sizes up, or more?), maybe go up one size on the pilot jet (maybe not), and shim the needles yourself to richen up the mid-range. (Note: The DJ kit has slotted needles.) Then you will have to read your plugs to ensure you have the proper air/fuel ratio for each carb circuit/throttle opening. You'll find info and links on my little website. Here's your "mega-welcome".

If you are here you probably have a 30 year old motorcycle that needs about 20 years worth of maintenance. In the links below you'll find maintenance lists, documentation, wiring diagrams, "how to" guides, vendor links, tips, tricks, and a whole lot of GS goodness. This is your "mega-welcome". Let's get started.

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!

More links to helpful threads in the forum:
Help! Your Bike Won't Start
DON'T DO THESE THINGS
Help! Your Bike Won't Run Well
Oh God! Pods!


Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[rslade274]

okay thanks a lot!!! I will start with a #104 jet and go from there. I already shaved the plastic spacer to effectively "shim" the needles because they do not have multiple slots for the clips. This raised them up slightly.
Also, what does chopping the plugs mean?
Thanks again for your help!!

[tkent02]

Plug chops, almost as good as pork chops......