Idle problems on predator 212
- Thread starter Predator212cc24
- Start date
- Tags 212 idle predator
I would double check the carb mounting gaskets and make sure they are on correctly, especially the two on each side of the insulator. Possible vacuum leak ...or the low side jet is clogged or low side circuit is clogged up. Low side jet is the black piece under the big black idle screw.
If you take out the low side jet check the two tiny o'rings on it and make sure they are OK. Oil the O'rings when you reinstall the jet.
If you take out the low side jet check the two tiny o'rings on it and make sure they are OK. Oil the O'rings when you reinstall the jet.
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Well It sounds like it's running too lean. Having to have the choke on to get it to barely run is setting up the exact opposite.
Too lean, hard to start, bog on acceleration, no power. You add the choke to somewhat compensate, by cutting off airflow.
Now you have an engine with little air and more fuel at idle. Open the throttle up and you dump more gas in it, with the choke on, so it starves for air and fouls the plug. Once fouled, I toss the plug. Too many times I've seen folks chase a problem all caused by a fouled plug.
I've seen fouled plugs spark like crazy when pulled from the engine. Yet when installed, the engine won't start, and the plug comes back out gas soaked like it wasn't firing.
If you increased the airflow via one of the bigger breathing air filters, and with a header that flows easier, then the fuel system needs to be adjusted to compensate. These motors tend to run on the lean side stock, and if the fuel system isn't up to the job making it flow more air is just going to make the problem worse.
One other thing. Load on the engine. Chain too tight, weak clutch springs, these put a load on the engine that shouldn't be there. Can cause the engine to start/run poorly at idle. So it won't run unless you richen up the mixture, by adding choke. Now you got a loaded up plug just to get the engine to idle. You give it throttle, dumping more fuel in an already over rich system, and the motor dies, as the plug fouls out.
My Predator ran like doo doo when I added a header and A/M airfilter. Like yours it wouldn't idle right, surged, and left alone would just die. Unless you had the choke part way on it would die if you tried to throttle up.
Installed a 36 Main jet, and new tube and it became a different beast. Now it will fire on the first crank, sit there and idle like a baby Harley, and crack the throttle and it's ready to rip the bike out from under you. More then enough for me, still has the governor on it.
Too lean, hard to start, bog on acceleration, no power. You add the choke to somewhat compensate, by cutting off airflow.
Now you have an engine with little air and more fuel at idle. Open the throttle up and you dump more gas in it, with the choke on, so it starves for air and fouls the plug. Once fouled, I toss the plug. Too many times I've seen folks chase a problem all caused by a fouled plug.
I've seen fouled plugs spark like crazy when pulled from the engine. Yet when installed, the engine won't start, and the plug comes back out gas soaked like it wasn't firing.
If you increased the airflow via one of the bigger breathing air filters, and with a header that flows easier, then the fuel system needs to be adjusted to compensate. These motors tend to run on the lean side stock, and if the fuel system isn't up to the job making it flow more air is just going to make the problem worse.
One other thing. Load on the engine. Chain too tight, weak clutch springs, these put a load on the engine that shouldn't be there. Can cause the engine to start/run poorly at idle. So it won't run unless you richen up the mixture, by adding choke. Now you got a loaded up plug just to get the engine to idle. You give it throttle, dumping more fuel in an already over rich system, and the motor dies, as the plug fouls out.
My Predator ran like doo doo when I added a header and A/M airfilter. Like yours it wouldn't idle right, surged, and left alone would just die. Unless you had the choke part way on it would die if you tried to throttle up.
Installed a 36 Main jet, and new tube and it became a different beast. Now it will fire on the first crank, sit there and idle like a baby Harley, and crack the throttle and it's ready to rip the bike out from under you. More then enough for me, still has the governor on it.
Whoops just thought of something. If this thing is running really rich, due to having the choke on to get it to run. Check the oil.
If this thing has been running like this for a while the oil could have some gas mixed in with it. If the plug isn't burning it, it has to go somewhere. Some out the exhaust, some gets mixed with the oil. So you could have oil that is adding more fuel to the fire so to say.
What I mean is with a perfect set up, fuel fouled oil can cause it to run richer. Mix that with running it in a lean condition, where you are compensating by cutting off the airflow is just making the situation worse, in the opposite way. Too rich and cause it to idle poorly and bog out or just die.
If it was me, I'd pull the carb off, see what main jet and tube you have, check the idle jet too. While the carb is off, toss the plug and get a new one. Change the oil, and crank the engine over a couple of times to help clear the combustion chamber of any left over fuel.
With your mods, the carb should have a 36 or 37 main jet and 140 emulsion tube at least. And check to make sure something isn't hanging up causing a load on the engine that shouldn't be there.
If this thing has been running like this for a while the oil could have some gas mixed in with it. If the plug isn't burning it, it has to go somewhere. Some out the exhaust, some gets mixed with the oil. So you could have oil that is adding more fuel to the fire so to say.
What I mean is with a perfect set up, fuel fouled oil can cause it to run richer. Mix that with running it in a lean condition, where you are compensating by cutting off the airflow is just making the situation worse, in the opposite way. Too rich and cause it to idle poorly and bog out or just die.
If it was me, I'd pull the carb off, see what main jet and tube you have, check the idle jet too. While the carb is off, toss the plug and get a new one. Change the oil, and crank the engine over a couple of times to help clear the combustion chamber of any left over fuel.
With your mods, the carb should have a 36 or 37 main jet and 140 emulsion tube at least. And check to make sure something isn't hanging up causing a load on the engine that shouldn't be there.
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I have no load on the motor currently as I have taken the clutch off the crank for now. Sometimes when I go to yank the pull start in jerks back i have checked the valves and they open and close correctly this have a stage 2 high performance kit on it from OldMiniBikes warehouse and I have a 6625 billet flywheel I ahve removed the governor but it is sealed up tight no leaks. Does anyone happen to know the exact specs for this mod as far as the spark plug gap, magneto gap, valve lash gap? Any help would be appreciated
So I'm taking it that you have the non hemi predator engine ?...so the 6625 flywheel should be right. Minimum air gap is .030 between the coil and flywheel...I usually run .040 myself, but some folks run a lot wider gap. Valve lash is .003 or tighter ...and adjust valves on compression stroke piston all the way up... plus a tad bit past tdc. Have you tried a new spark plug yet ? If not try a new plug gapped from .030 to .040. Kick back is a sign of something out of time or the valves are to loose.