Initial float level setting GS850

[bobgroger]

Hi, I am rebuilding my carbs after the bike sat for 18 years. The motor was mildly stuck but after PB Blaster in the spark plug holes it freed up in a couple days and has compression in all cylinders. The carbs are squeaky clean and I am reassembling everything with new orings and gaskets, a clean tank, and rebuilt petcock. I could not get one pilot adjust screw out, hopefully that will be OK until I can deal with it by finding a spare carb or attempting drilling and easy-out. My question is if the static float measurement in the manual is correct? It shows 22.4 mm from the gasket seating area to the first step on the float. Mine were all set to 22.4mm to the topmost part of the float, and getting them to the specs as shown in the manual requires some pretty serious bending of the tang. I am trying to fab up a level measuring tool to screw in the drain plug hole, but I am curious if following the specs in the manual will get me close....

Bob Groger
1980 GS850GT

 

[Nessism]

I suggest you don't proceed until you get the pilot screw out. Cut a slot in the screw, and carb tower, with a dremmel cut off disc as needed to make a new slot. Use PB Blaster and heat until you get the screw out and the passage cleaned.

Are the float needles weak, allowing the spring to compress due to the weight of the float alone? If so, I'd replace the needles. Something sounds off somewhere. Check my signature for a carb rebuild tutorial in case you haven't seen it yet.

 

[Steve]

Cut a slot in the screw, and carb tower, with a dremmel cut off disc as needed to make a new slot.

It will look like this when you are done.

.

 

[bobgroger]

Thank you both for the replies. I was very anxious to see if this ran well enough to put more money into it, so I built the float level tool from a short length of 3/16 brass tubing which I soldered to a drilled out drain plug, and a length of clear tubing. This put the level at ~4-5mm below the gasket surface, and no leaky needles. Put it back together and with a shot of starting fluid and full choke, a huge cloud of blue smoke enveloped the neighborhood. The cloud dissipated after a few minutes, and it seems to run reasonably well for not being synced and the rings have not yet re-seated. I need to get the brakes bled, then will take a short test ride and see how it does...... I can fine tune later if needed, removing the carbs is not a big deal. Getting them back in to those 33 year old hard rubber boots proved to be a challenge, but leverage and a 2x4 worked fine....
This is a 15k mile bike I bought from the original owner's estate, and it is pretty pristine for its age.

 

[Steve]

After that first ride pastes a permanent grin on your face, be prepared to dismantle the carbs for a full "strip and dip" rebuild.
You should also do a valve adjustment to make it run that much better.

While you are at it, get ready to spend a few bucks on new intake boots. They are about $28 each, but worth EVERY penny.

.

 

[BassCliff]

Greetings and Salutations!!

Greetings and Salutations!!

Hi Mr. bobgroger,

You will find lots of GS850G lovin' on my little website, along with lots of information on how to perform proper maintenance on your 30 year old motorcycle. Here's your "mega-welcome". :dancing:

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

 

[bwringer]

Floats on these carbs should be measured at the step, exactly as shown in the manual.

It's depressingly common to find that some doof has set float heights at the top of the floats.

It's even more depressingly common to find that someone has installed low-quality dangerous imitation parts from a rebuild kit.

If the spring-loaded nubbin in the float needle won't hold the float up when the carb is upside-down, they're imitation parts. Even if you can get these float needles to work, they wear quickly and create a very dangerous gas leak.

You will also want to check the needles and jets to see if they're OEM genuine Mikuni parts. With the possible exception of the bowl gasket, none of the parts found in rebuild kits are usable.