hi guys,
when I close the engine crankcases the piston turns harder, as if the clutch pack is touching against the inner crankcase. But I don't hear any rubbing noise.
So I am wondering if this is normal or not. I'm sure I reassembled the engine correctly.
Any thoughts?

Are you using the correct tools?  Crank shims in place?  Was crankshaft rebuilt and width checked to be in spec?

I confirm

Hmm, does it turn easier iif you release the screws a turn. If you mean the crank is harder to turn i often give the crank a tap each end to unstress it. Just my maybe bad idea but works for me. Once the crank gear nut is tightened then the seal will have slight drag. Could remove the clutch pack to stop the gear internals revolving so you only have the clutch basket & kick idler gear turning. But if you mean the piston is tight to go up & down in the cylinder then it will bind a little with ring pressure & drag. All a bit of a guess sorry. ps, i meant i tap the crank on the gear end when the nut is tightened as if the crank was fitted into the left case & then right case fitted then when the nut is fitted to the gear the nut will try to pull the crank over to the right side bearing. But the left side bearing will be holding it but finaly letting it go--only talking a little bit. But that little bit is under stress until given a tap hard enough to center it. Makes a difference. If you can follow my woffling on. Pretty much a long version of what Mark said above.

if i'm understanding what you're saying here, you are talking about the two crank case halfs.You're turning with no outer case on and saying when your at the stage of  "clutch on,ready for outer cases going on",the crank is hard to turn?
I take it you're also trying to turn it over by hand  with no spark plug in?
If you haven't solved this by now,i would remove the clutch and try turning.
Then the barrel and piston.
No different,then remove the left hand crank case because something isn't right .
Get it where you have the crank in the right hand case and turn it then with the primary gear and collar in place. If that turns easy then you know that bit is free. Check the clearance as im sure that side is shimmed.
Get the parts book out and compare what you have and where it goes and re assemble checking each time you put something in for rotation.
Fit the left case and when its closed up,check everything turns again. If it's good then put the screws in.
Again check for ratation.
It will cost you a bearing and some time.
The rest is solvable without a problem.
Keep us posted .
regards
Shyted.

 

You are so kind.
I solved it. It was the shim of the tachometer (nr.4 in the manual). It was too thick and was causing friction. Replaced it with a thinner one and everything works fine.

Haha well that's one thing i didn't think of, so outer cover was on!!. Wonder where the 'too thick' shim came from. Anyway--good job.

I was thinking the actual crankcase and not clutch cover...  I should have known better because it was said the clutch may be rubbing. 

CT's need to have the factory thickness clutch cover gasket in place or the plastic tach drive will bind up...  no gasket will lock it up solid with the original shims.

yeah i was thinking originally maybe something behind the clutch & cover off haha.