Starting to strip my engine down today, when I took the barrel off I noticed oil on the flyweights. 

 

Now, I thought the gear case and crank were separate, so oil must be leaking into it somewhere. I'm splitting the case so a new gasket will be fitted but I think I've found the culprit.

 

There's no way, even twin seals will stop oil passing with pitting like this.
I'm now coming to the conclusion my engine has probably been sitting somewhere for years, before being brought back to life, quickly freshened up, and sold to me!

 

you can also see rust on the flywheels, hence, suspect being stored without oil etc.

 

A chance to do it justice and really do it right!

I'd consider rebuilding that crank.  Rod bearing won't last long at all if it got rusty at some point. 

Definitely sending the crank off then, just still waiting to hear from the machine shop, to see if my head is toast  .

The build is on!

Finallly got my barrel back after it had to be re-sleeved, my shop took along time but two stroke restoration has gone ballistic here in the UK, they were telling me currently they are refusing any more new jobs, they just can't keep up! Luckily I got in just in time.



      

I don't see the ports being chamfered? You'll possibly break a ring if you run it like that. I don't have a lot of engine building experience but hopefully more experienced guys will look closely at the ports. The first motor I did a few years ago the machine shop was sure to point out how they chamfered the ports. Since then I note that on all my builds and even notice it on used cylinders. Someone will chime in. Your port edges look too sharp to me. Might just be me though!

Can see a little chamfer--i think. Looks like a realy nice sleeving job. Did they make one from a blank or was it an LA Sleeve --sleeve. or Wiseco sleeve. Looks expensive but VERY nice.

Very fortunate the cylinder was able to be saved. Was it bored, or sleeved?

That drive gear can be replaced, and I would if I were you. Should be able to find a new one, even, maybe? 

Agree with MarkT that the crank should very definitely be seriously looked at before putting back in service. Especially after putting the effort and expense into the cylinder work.

I am sure it was a very disappointing experience for you to have that failure on an early ride, anticipating a nice easy ride-about and all. I have been there too. 

yes, it’s has been chamfered, the shop has completed everything, including a wash. Apparently the sleeve material came from the EU, hence the long wait but I’m very pleased with the work.