Is there is side to side play in the crankshaft itself then it sounds like the main bearings are bad. If you already have it turn down take a close look at the crank and inspect it fir damage and wear where it rides on the main bearings. Also have a close look at the bearings themselves. I would plan on a complete rebuild. How long has this bike been sitting? Was it running before you tore it down?Scottie J
I don't know about the Clipper, but the Bullet takes up the crank end-play when you tighten up the alternator nut. Until you do that, the crank moves side to side about an eighth of an inch. When you tighten the alternator nut, it pulls it all out to one side, and then the crank is centered and doesn't move side to side.As for the main bearings, yes, I always change main bearings when I have the cases split, regardless.
That radiused fillet you point out is not a problem. It is done like that to keep the crank from cracking there.The area of concern is the inboard segment of the crank where the rollers run, and there are two black bands on there that look like burnt oil. That area must be completely smooth and round, and the proper diameter for the rollers to run on it properly. If it is not, then a new timing side shaft is called for, or a proper metal surface repair and heat treat for rollers should be done to that shaft you have. The clearance for the rollers is quite precise, and the surface needs to be quite hard, and it all needs to be perfectly round, and smooth and even.Get a figure from a service manual, or from Hitchcock, on the proper diameter of that shaft in the bearing area. Then you know how close you are to being good, or how far out it is.Regarding the big end, if it passes the no up/down play test, it is probably okay. However, we don't know how long it will stay that way. It is unknown for future lifetime.
If you don't already have it, here is a link to Hitchcock's in the UK.http://www.hitchcocksmotorcycles.com/news/22616/Additional_Online_Parts_BooksThey show parts for the 250cc Clipper and the Crusader and just studying the drawings can help you understand what goes where.Although it's a PITA paying the shipping costs, their about the only good source for parts for many of the RE models like yours.
In my manual it says the engine shaft diameter is 1.0000/.9997 I don't know why there is a slash and then another number though. should I use steel wool or something to get the oil off and then measure it? One problem is my caliper only goes to 3 decimal places and these numbers go out to 4 places