Questions about my 1996 DS80

[my67xr]

Sound's like either there's something stuck in the needle and seat, and that's not letting it close properly, or the centre tab on the brass float arm might be bent?
Have you replaced the fuel hose ?
Old hose can get brittle and a small piece may have come off and be stuck in the carbys' needle and seat.

If the needle and seat is clean, then the tang on the float arm may be bent
Take the carby off then the fuel bowl off,
Hold the carby upright and check that when the float is lifted so the float arm centre tab is just touching the pin in the bottom of the needle, the bottom of the float should be about 25mm off the fuel bowl mounting face (bottom of carby)

You can even connect up the fuel hose and turn the tap on, check that when you lift the float that the float arm is parrallel to the base of the carby and the fuel should stop running out the bottom of the needle and seat.
If the float need's to be raised more to shut off the fuel then the centre tab need's to be carefully bent up a little


Your carby is a Mikuni VM22, the dimension are down below in the pic

Standard jetting is a #25 Pilot jet, and #87.5 main jet
Suzuki Motorcycle Parts 1996 DS80 CARBURETOR Diagram

 

[velociraptor]

Ok so i was off lol #25 i figured i was wrong my issue with the vm22 is be careful ordering jets there is like two types offered for them at least here there is

 

[cb750mike]

I think I fixed the leaking issue. I bent the tab a little more cause I realized at the angle the carb sits at the float doesn't fully close the valve. Now it doesn't leak so I'll run it around the neighborhood and let it idle and see what it does.

 

[my67xr]

The carby float bowl should sit pretty much be parrallel to the ground.
Lowering and raising the float height more than needed can make the bike run lean or rich too, so try and keep it close on factory setting's

 

[velociraptor]

What he said lol on the ds 80 the higher stock tolerance will leak a lil on the kickstand and at least for the american model it sits with a little angle and if you dont match the tab on the end of the carb with the slot on the rubber intake boot it can leak as well

 

[cb750mike]

It pretty much is parallel. I didn't bend the tab much just a tiny bit to where I noticed it closes the valve more now. I have the tab in the slot and also I have the bike straight up. It was just pouring out of the main jet. Hopefully this will help it run better too. It seems a bit off.

 

[my67xr]

The main problem i've found with the DS80 carby's is the pilot jet port at the bottom of the thread's in the carby base is blocked up, or semi blocked. (bottom hole in first pic below)
Poke a thin strand of copper wire through the hole and take note if any gum/varnish come's out.
And check that the emulsion tube has all the hole's across it open too. (bottom pic)
Also check that the hole where the slide needle slip's into is round, if it's worn oval shape then you'll need to replace it as it'll run too rich

 

[velociraptor]

Xr is the man on this stuff . dont forget to check the needle for wear marks too as this will cause issues in the various stages of throttle and a rich condition you wont be able to fix with adjustments.

 

[cb750mike]

So I started it today and it runs fine on choke but won't idle off choke no matter how high I try to put the idle. Could this be cause I have the float too low now? When I'm coming off (idle) or trying to keep it alive and give it throttle. At first it spits fuel out the inlet and then revs up normally. I tried adjusting the pilot screw and still won't idle and spits fuel out. I'm lost now. But there's some excellent info above thank you for that xr! I gotta get a set of jet files so I can clean everything.

 

[my67xr]

When you are trying to start the bike, is the air filter box on, filter fitted and cover screwed on?
If it's not then it'll make the mixture's too lean, and won't be helping the situation.
After cleaning the air filter element, make sure you spray some foam filter oil onto it so that it can stop any dirt getting though into the carby and causing more problems.
It's only cheap, and available in an aerosol can from any automotive part's place.
If it doesn't have a filter at all, then you should be able to pick up a cheap pit bike type pod foam air filter and some filter oil for it for under $20
I ran my DS80 with a pod filter for 2 year's, but it needed a bigger pilot jet(#35) to get the mixture's right as the pod filter let's it run quite lean compared to the original filter box etc



Do you have any old automotive wiring laying around ?
If so, strip back some of the plastic insulation and cut off a couple of strand's of copper wire and use that to poke through the hole's.
I would take the carby off the bike to do it.
Make sure the hole's i told you about are all open, double check the pilot jet too as that's the one that let's the fuel/air through for the idle circuit.
Also while the jet's are out, remove the mixture screw and spring
Now use some carby/throttle body cleaner and spray it directly into the hole at the bottom of the intake side of the carby.
some spray should come out the mixture screw hole when you do it.
blow some compressed air through the hole too.
Next refit the mixture screw and spring and tighten it till it nip's up.
Then turn the screw back out 1.5 full turn's, this will be a good base setting to get the bike started when it's back together.
Spray some more cleaner into the same hole on the intake side, and check that it come's out the pilot jet hole in the base of the carby (where the pilot jet screw's into)
Blow the carby out well with compressed air again.
Now refit the pilot jet and do it up till it just nip's up tight.









I mentioned removing and checking/cleaning the emulsion tube before.
But didn't say how to take it out.
With the top of the carby off and the cap and slide removed if you look down into the carby you'll see the top of the needle jet/emulsion tube
To remove it you need to take the main jet out and the washer off the end of the tube
You should be able to gently push the emulsion tube out through the top of the carby
Sometime's they get stuck from sitting unused for year's, you can screw the main jet back in without the washer and gently using the plastic handle of a screwdriver give it a few tap's in, this should be enough to break the bond between the gum/varnish that's holding the emulsion tube in
Don't be to rough doing this as you may damage the tube or jet.
If it's stuck in there good you might need to soak the carby in Yamaha Carby soak overnight to dissolve the gum
Try some WD40 too, let it soak in for a while before tapping it.

Measure the float height again, check that it's about 25mm away from the fuel bowl mounting face on the bottom of the carby when the float arm touches the pin in the end of the needle (needle and seat).
If it's too low then it will make the carby run too lean, it'll pop and backfire through the carby and will be quite hard to start.






And check the hole's through and across the pilot jet are open

After doing a thorough clean out you'll need to adjust the mixture screw when it's back together to make it run best.

Start the bike and let it idle and warm up.
Once it's warm you can adjust the mixture, turn the idle speed screw in about 1/2 a turn to raise the idle speed
Now adjust the mixture screw in or out 1/2 turn at a time, let it settle for 10 second's and listen to the way it run's.
You want to find the highest/smoothest point , so it may take a couple of tire's to get it right.
Once you think it's close to the best smooth idle,
then you can turn the idle speed screw back out about 1/2 turn or so till the idle is a normal speed again.

Give the throttle a few blip rev's to check it's not backfiring etc.
If it's ok then try the bike out and see how it goes.

if you need to adjust the mixtures to tweak it now, just turn the mixture screw in or out a little (1/8- 1/16 of a turn) at a time to find the best setting
it won't be too far from where it was adjusted to, and remember to let it settle after each adjustment by leaving it idling for 10 second's or so after adjusting it.

 

[velociraptor]

The jet files?? Just get a set of mig welding tip cleaners exact same thing just about just the sizes are usually standard not metric so ud have to go undersize a lil on some

 

[velociraptor]

Spitting fuel out where i need to ask? Exhaust or filter area? On a two stroker you will get a small amount on the filter usually with the ds 80 its only induction reed valves so there is still alot more back pressure it kindof helps keep the filter oiled if u ever work with a leaf blower ect notice they do the same even when brand new. If thats not it and its coming out the exhaust id go with what xr is saying as per setting the mix it takes patience as rushing it heeds poor results usually. If the mix dont fix it check everything from ur plug type and gap to compression every bit of info helps

 

[my67xr]

A mig tip cleaner's will be a bit too big to clean the pilot jet.
Most tip cleaning set's i've seen start off at .38mm and go up to 1.6mm, the smallest .38mm cleaner tip is close on a #38 pilot jet, and will be too big unless the engine is on it's second oversize, or is running an aftermarket exhaust or pod filter etc
They also stuff up jet's easily due to being a file.
If you are slightly off square when running the tip cleaner through the jet it'll oval the bore and it won't flow correctly.
The copper strand's of wire are the best to use as it won't scratch/enlarge the bore of the jet as easily

I'm not sure how you are noticing it spitting fuel if it's out the carby ?

Spooge out the exhaust i can understand.

 

[velociraptor]

Is the filter off?

 

[cb750mike]

Right now I'm having issues with the tube from the airbox to the inlet of the carb. So after it came off I just kept it off since it's a pain in the arse and doesn't fit properly and that's how I'm seeing the fuel spitting out the inlet of the carb when I go from low rpm to full throttle. But now reading I see that it could be adding to my issues. I bought a new filter element after I got it. But I may need to make sure the jet holes are clear and the floats are at the proper height.

 

[my67xr]

Yeah they are a painful thing to try and fit back on.
I had to reshape mine with a heat gun, if you try it don't get it too hot
I guess that the air box snorkel wouldn't be too expensive new too, Jr80 snorkel's probably fit too
Nice looking second hand one-
Suzuki DS80 DS 80 JR AIR BOX Airbox Boot Intake Hose Carb Rubber 96 1996 | eBay

 

[cb750mike]

It seems too short too. I don't understand why cause the air filter box is mounted correctly and the carb is too. But here's another curve ball that I'm not sure if it would be adding to my problems. My cylinder walls were scarred up pretty bad so I had to go 1mm bigger in piston size. Would this be an issue as well?

 

[my67xr]

It might have been bored and had an oversize piston fitted before you got it?
Did you hone it before fitting the new piston, ring's and gudgeon bearing so the ring's will bed in properly ?

 

[cb750mike]

Yea the shop I took it too bored it out and then honed it for me so it was ready to go. I've noticed a lot of fluid coming out of the exhaust. Why is there so much?

 

[my67xr]

Black spooge coming out the exhaust ?
So you are still running premix ?
What ratio ? eg how many ml's oil to how many litre's of petrol ?