[SpudRider]

Thank you, Weld.

Regarding the welding, I must confess I got lazy. I should have posted, "I coaxed my good friend Andy to weld some extensions onto the center stand." I will go back and correct my post. I did a little stick welding back in the 90's, but I need to get that Eastwood welder you recommend.

The board adapter works very well. It provides a nice, wide and stable platform for lowering, and raising the engine into place. I used it to remove the stock engine, and install a Yamaha XT225 engine in my Zongshen Sierra. The adapter worked equally well with the NC250 engine in my RX3.

I have not confirmed any other valves which fit the NC250 engine. Of course, the problem might also reside with the valve seats. So far, the valve clearances are holding. I hope the new valves and cylinder head have solved the problem.

Incidentally, I also installed four, new valve springs during this engine work. The cam chain was in very good condition, and did not exhibit any elongation, as the timing marks aligned perfectly.