My son and I are trying to finish a mini bike build, and we are struggling with the 212 Predator. Here’s what we’ve done.
We removed the Predator fuel tank, air box, and exhaust, and replaced them with a custom made fuel tank, stage 1 intake and KN style air cleaner, and a header with a screw on muffler. I also installed the smaller jet and emulsion tube that came in the stage 1 kit. We did not install the beefy valve springs or offset flywheel key.
We did not run the engine in factory form. When we tried to fire it up, it would not start. I verified we are getting spark, it’s a very light spark, but it was sparking. We finally got it to start by squirting some starting fluid into the carb. Once it started it was smoking and running poorly. It would not idle smooth, and the engine would speed up and then slow down to the point of almost stopping running unless I bumped the throttle. Also, when any throttle above just a crack, it would cut out like it was running out of fluid. I suspected our gas tank was the issue, because the cap was not vented. I added a vent to the cap with no change to the poor idle or cutting out.
Then I assumed the jet and emulsion tube was the culprit, so I swapped the stock jet and emulsion tube in, and it ran the same. Then I started to think it was a vacuum leak, so while the engine was running (poorly) I sprayed some starting fluid between the carb and plastic plate it mates up to, to see if the engine would speed up, but no change. I also made sure I had the thick steel and rubber gaskets on both sides of the carb.
I have another Predator I plan to put on another bike, so I unboxed it and pulled the stock carb off of it. I installed the carb from the fresh from the box engine, and it will start without starting fluid, but runs the same (poor idle and cuts out with any throttle applied).
I’m out of ideas. I assume it’s something simple, but I have no idea how to fix it.
Should I install that offset key? Is that my problem? Surely the stock valve springs are not the issue, but I’m not ruling anything out at this point. Anyone have an idea what my problem is with this engine???
We removed the Predator fuel tank, air box, and exhaust, and replaced them with a custom made fuel tank, stage 1 intake and KN style air cleaner, and a header with a screw on muffler. I also installed the smaller jet and emulsion tube that came in the stage 1 kit. We did not install the beefy valve springs or offset flywheel key.
We did not run the engine in factory form. When we tried to fire it up, it would not start. I verified we are getting spark, it’s a very light spark, but it was sparking. We finally got it to start by squirting some starting fluid into the carb. Once it started it was smoking and running poorly. It would not idle smooth, and the engine would speed up and then slow down to the point of almost stopping running unless I bumped the throttle. Also, when any throttle above just a crack, it would cut out like it was running out of fluid. I suspected our gas tank was the issue, because the cap was not vented. I added a vent to the cap with no change to the poor idle or cutting out.
Then I assumed the jet and emulsion tube was the culprit, so I swapped the stock jet and emulsion tube in, and it ran the same. Then I started to think it was a vacuum leak, so while the engine was running (poorly) I sprayed some starting fluid between the carb and plastic plate it mates up to, to see if the engine would speed up, but no change. I also made sure I had the thick steel and rubber gaskets on both sides of the carb.
I have another Predator I plan to put on another bike, so I unboxed it and pulled the stock carb off of it. I installed the carb from the fresh from the box engine, and it will start without starting fluid, but runs the same (poor idle and cuts out with any throttle applied).
I’m out of ideas. I assume it’s something simple, but I have no idea how to fix it.
Should I install that offset key? Is that my problem? Surely the stock valve springs are not the issue, but I’m not ruling anything out at this point. Anyone have an idea what my problem is with this engine???