Mafia_zs
Member
Hi can someone please give ne some baseline jetting the bike has a z40 cam other than that its bone stock.
Cheers
Alex
Cheers
Alex
Baseline jetting oko 26mm Yx140
- Thread starter Mafia_zs
- Start date
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my67xr
Miniriders Legend and Master Spanner Spinning Mode
I reckon the standard jetting should be spot on for the 140 / OKO 26, 36 Pilot 100 Main
try it out, if there is any hesitation when you blip rev it, then go for a #38 Pilot.
try it out, if there is any hesitation when you blip rev it, then go for a #38 Pilot.
Mafia_zs
Member
Ok thanks very much mate
I have just put an OKO 26 on a lifan 150
But the issues I am having is on start up without touching the throttle it almost hits the limiter then backs down to idle
Idle is still rough can't find a really nice spot for it at all
When riding it surges
Can only hold it about 1/4 throttle to keep a semi consistent rev range any higher and it will die then go then die again
Backfires all the way through every rev range
Any thoughts?
I was wondering if it's possible the floats are set to high and it's holding way to much fuel
The float almost bottoms out before sealing up completely I have looked at other floats and the all have a little bit of a spring back if you push them right to the top this one doesn't
Thoughts please
But the issues I am having is on start up without touching the throttle it almost hits the limiter then backs down to idle
Idle is still rough can't find a really nice spot for it at all
When riding it surges
Can only hold it about 1/4 throttle to keep a semi consistent rev range any higher and it will die then go then die again
Backfires all the way through every rev range
Any thoughts?
I was wondering if it's possible the floats are set to high and it's holding way to much fuel
The float almost bottoms out before sealing up completely I have looked at other floats and the all have a little bit of a spring back if you push them right to the top this one doesn't
Thoughts please
my67xr
Miniriders Legend and Master Spanner Spinning Mode
What jetting is in it?
And how many turn's out is your mixture screw ?
Revving high from first start, and then slowly dropping back down is too lean, surging when riding is too lean as well.
Have you checked for air leak's ?
And how many turn's out is your mixture screw ?
Revving high from first start, and then slowly dropping back down is too lean, surging when riding is too lean as well.
Have you checked for air leak's ?
my67xr
Miniriders Legend and Master Spanner Spinning Mode
You didn't mention the jet size's in your post ?
With the float being able to go up higher, that sound's normal with OKO carby's.
The needle and seat has a pin and spring inside it, once the tab on the float arm touch's the pin, the needle is starting to close then.
By the time the pin is compressed 2mm into the needle the seat is closed, but the float is still able to move up a bit more from there
If you want to check your float level, hold the carby like this pic show's
The bottom of the float should be 19mm off the base of the carby with the float just touching the pin on the needle.
Are you running a decent and oiled foam filter on it ?
Not just the oil what the come with, you'll need to buy some air filter oil and spray or squeeze it through the filter to catch any dirt/dust etc
If you haven't oiled the air filter then that will make the bike run lean, especially at higher rpms.
To check the carby/manifold etc for vacuum leak's,
start the bike and let it run for a minute, then while it's still running spray some wd40/degreaser etc onto the join where the adapter meet's the intake manifold, and manifold to head joint.
If the idle speed, or the idle change's in any way then there is your leak.
When you bolted the OKOs' rubber adapter to the intake manifold, if it was done up too tight it might have warped the mounting face of the adapter, it's only 5mm thick aluminium inside the adapter.
That would let it suck air (vacuum leak) past the rubber o'ring into the air/fuel mix coming from the carby and make it quite lean.
You might be able to square up the mounting face by rubbing it across a flat sanding block with some 180 grit sandpaper on it if it has warped.
Also remove the rubber o'ring and make up a new thick paper gasket (1mm - 1.5mm) to the same size as the manifold face.
That also help's lessen the chance of the manifold warping.
With the float being able to go up higher, that sound's normal with OKO carby's.
The needle and seat has a pin and spring inside it, once the tab on the float arm touch's the pin, the needle is starting to close then.
By the time the pin is compressed 2mm into the needle the seat is closed, but the float is still able to move up a bit more from there
If you want to check your float level, hold the carby like this pic show's
The bottom of the float should be 19mm off the base of the carby with the float just touching the pin on the needle.
Are you running a decent and oiled foam filter on it ?
Not just the oil what the come with, you'll need to buy some air filter oil and spray or squeeze it through the filter to catch any dirt/dust etc
If you haven't oiled the air filter then that will make the bike run lean, especially at higher rpms.
To check the carby/manifold etc for vacuum leak's,
start the bike and let it run for a minute, then while it's still running spray some wd40/degreaser etc onto the join where the adapter meet's the intake manifold, and manifold to head joint.
If the idle speed, or the idle change's in any way then there is your leak.
When you bolted the OKOs' rubber adapter to the intake manifold, if it was done up too tight it might have warped the mounting face of the adapter, it's only 5mm thick aluminium inside the adapter.
That would let it suck air (vacuum leak) past the rubber o'ring into the air/fuel mix coming from the carby and make it quite lean.
You might be able to square up the mounting face by rubbing it across a flat sanding block with some 180 grit sandpaper on it if it has warped.
Also remove the rubber o'ring and make up a new thick paper gasket (1mm - 1.5mm) to the same size as the manifold face.
That also help's lessen the chance of the manifold warping.
Sorry haven't had time to check it out again yet was going to on the weekend but ended up being a big one lol
With the jetting I mean same as the other guys 36pilot and 100 main
I will deff check the float though cos I think when held like that it is almost sitting on the carby when it touches the pin
With the jetting I mean same as the other guys 36pilot and 100 main
I will deff check the float though cos I think when held like that it is almost sitting on the carby when it touches the pin
