Crank is just fine.
 

Well 2 new valves and lapped them in, new head gasket, smoothed up the sticky timing chain tensioner and bought a new spring for it and a new head gasket.
Set the timing on the loose side of spec .010 intake and .012 exh thinking the valve may wear in pretty quickly the first hour or so (my guess anyway) Threw a couple tubes in the cracked rear tires and went for a ride. Some oil smoke at first but seems to have cleared up after a short ride.
If the cam timing was slipping, I think the chain was jumping. I have run it a hour since I re did the tensioner and it has not jumped. So the crank is fine.
The rest of the bike seems to work without any serious troubles. Next big fix is the stripped shifter pedal and some new rear time.
It runs nice but is touchy to re start warm. Choke on and off, sometimes still a lot of cranking to get it to run.
Runs great once its going. So better check my valves again, or perhaps a comp test, see if I can talk my buddy out of his tester for the pesky little spark plug.
Further I know ther are no other major issues, so I think I'm in the clear.
Ken

Nice bro! Long live the moto4

Well it has been a long time coming but just a update. The Moto 4 is doing well. But continued hard start, especially when cold. I was thinking the rings where still seating for awhile.
I rebuilt the carb, new spark plugs. Rechecked my valve lash etc. But after After 12 months of wearing out the starter or push starting it cold to get it to run. (starts good warm) I finally dug into the ignition. Wire and grounds looked good.

I always had spark, but a spark gap tester confirmed it was weak. ($6 well spent)
I also bought a proper compresion tester to fit that damn mini plug, and it was 156 lbs.

Comparing the spark on the tester to my Honda XR70 dirt bike confirmed it was weak.The honda spark was much fatter and the engine would not miss fire at a idle until I increased the gap on the tester to @ 5/8"

Testing the external coil showed the incorrect ohm reading, so I replaced it first, being that was easier. No help though.
The internal flywheel coils were off on the ohm reading too. So I splurged another $40 for both new ones. Before the spark would barely jump 1/8 gap on the tester. Now it will jump over a 1/2" gap through the tester on the starter or running at a idle.
Best of all the old moto 4 fires off right away. It don't even need choke now. Crank and it fires up, blip the throttle a couple times until the heat builds a bit and it will sit and idle all day.

My advice if you are fixing a 20 year old bike and having start problems, check the ohm readings on your coil and stator coils against a manual. If they are out of spec. Change them out.
$55 on ebay for coils and this thing starts like new, like it was fuel injected.
Best of all my kids can start it, and I'm not wearing out the starter for nothing.
Ken