Need some help advising my mechanic 81 KDX

Hey all, trying to revive an 81 175 I bought awhile back, to make a long story short-when I got the bike the kick idler gear
and the gear on the kick shaft had teeth broken off and the clutch cover was cracked on top of the hole for the kick shaft. We replaced the parts and tried to kick it over, bam broke another clutch cover (Im on the fourth one now and rapidly depleting the world supply of these things). The kick shaft has some play in it, and when the bike is kicked over it almost feels like it is hydro locking, we get a popping sound and the lever pushes back. Mechanic says he talkeed to some fellow experts and concluded that the shaft can have a little play in it, not sure where to go from here. He said compression is high at 200? Would having fuel in the pipe from a flooding issue cause this? I was hoping some of you may have been through these symptoms before. My mechanic is very experienced and builds race engines for all kinds of teams, Im stumped as to why he is stumped.

This old bike thing is getting frustrating! Man it has comsumed so much time, all the while my 08 KTM is a flawless joy and helps me win races. Anyway, Ive got about 550 into bike and parts and now almost 400 in labor and still have a pos that doesnt run, this mechanic is a well respected race shop who should have no prob with an old air cooled 2t. He mentioned that maybe the cases need to be split to check bearing around the shaft to the tune of another 400, (we would of course replace all the other bearings and seals). The question is should I give up due to cost? Theres so many perfectly clean old bikes out there for under 1000 freshly rebuilt that run great (IT 250, 82 CR 125, 81 CR 125, cool bikes) that I could buy, I hate to give up after almost 1k. I just want an old Kawi to ride!