We rebuilt the engine because crankshaft bearings went bad! Crunched! Motor went together ok. When I start it the throttle only opens up about half way. HELP. Any ideas?

 

Do you mean the throttle is open half way when you start it, if so adjust the idle screw on the side of the carb, but if you mean when you accelerate, then adjust your throttle restrictor on the throttle box, but if that does not fix it then you have something internal like the throttle box, cable, or the carb spring

 

When I open up the throttle fully the motor only is running at about half.
As I release the throttle the motor slows down. I cannot get it to run on idel no matter what I do with the idle screw. The only way I get it to idle is to keep my finger on the throttle. Could this be a timing issue? It does start ok with my hand on the throttle. I have the air mixture screw out 2 5/8 turns. But I do not see much difference if any there if I try to make adjustments there. Before we rebuilt the motor we did not have this problem. Thanks for you comments. Any comments on this will be listened to.

 

Can you upload a video of what you're talking about, it will help to understand what's going on. I had many troubles with my 230 when I first got it, took over 5 months to get everything right. Also did you recently rebuild the top end, or mess with any of the valves?

 

I had to replace the bearings on the piston arm, and the piston. The piston that was in there was a domed piston. The ring gap closed tight on the rings. Not a good thing. I put in a OEM piston, flat top. New bearings on the crank shaft. I had to have that done by Suzuki as the crank is pressed together. They did a good job. I put the new piston in. I did not at that time do any thing to the valves. Saw no need to. Put the motor together. It started ok. The motor seemed to only go about half speed. My son and I checked the valves. We thought they were a bit on the shallow side so we adjusted them both. We ran the motor and there does not seem to be any improvement. Still at about 1/2 speed. What would happen if the timing was off a tooth or so? Next we are going to look at the throttle components.