I have a 31cc Ryobi I have converted and the engine runs great except for on thing. The engine seems to vibrate so mush the coke starts to close while I am flying. This causes a big problem. I have a rubber band setup on it to keep the choke open, but I don't like this idea. Are any on you out there having the same problem? I need to figure out how to get the engine to be a smoother running engine or do something with the choke. I am thinking of just taking the choke off for now. What do you conversion wizards suggest? I believe my vibration my be due to an unbalance MAS 18x8 prop?

Thanks

Did you balance the flywheel?

Enjoy,
Jim

Walbro carbs come from the factory with a small spring and ball detent..The ball fits into a depression in the shaft..If both are present the choke can NOT vibrate closed..If the choke shaft was removed and replaced the ball and/or spring might have been lost....
There a a few Walbro carbs, HDA 6A being one, that have a spring loaded link on the end, but I don't think the Ryobi carb is one of these...

Ralph is correct. All of my Walbro choke levers operate such that I can cearly feel a strong "click" when the ball falls onto the detent. I can't imagine an engine vibrate enough to make it jump out and stay off of the groove.

Depending on the orientation you have on the choke lever, you can hook up a pushrod with clevises on both ends. Fix one end to the choke lever, clip the other end onto a fixed point on your fuselage (you can screw a control horn to the side of the fuse for this). Now, you can unhook the clevis off the fuse and work the choke with the pushrod. Then when your engine has warmed up sufficiently, clip it back on the control horn, so it will never come loose in flight. You can even set up another control horn to hold the choke closed.

Jim, if your using the standard plate that slides sideways across the carb like the motor used while it was a trimmer, you might have to bend it a bit so the stamped indent fits into the notches ment for full,half and no choke. It might be possable to have it installed backwards too, just turn it over in that case. piper

Thanks everyone for you suggestions. I do have a balanced flywheel I got off of Peter and weedwacker.com so I know that should not be the problem. I well check my choke lever and plate setup. I know it is not on backwards for I have already checked. I did take this choke off of another engine so I my be missing to spring that was mentioned. I have not balanced my prop so I thought that might be the cause of the problem.

Thanks

Jim:
It's a ball and a spring. Needs both to get the correct length.

My Ryobi carb have a 'wave' washer that provides tension to assist keeping the Ryobi lever in place. Check to make sure it was not misplaced.