my kiddo's LTA50 ran hot from the second I picked it up used, Just figured poor piston to cylinder heat transfer from a worn top end was the problem. Got a fresh top end (properly bored with wisco piston) installed and its now running hotter! Iv never seen a air cooled 2 smoke run so hot! I shut it down after it starts making bad noises- Any ideas? see video:

 

How much clearance was the piston set at?
Piston in backwards?
I'd prolly pull the head and look in the cylinder.

 

When I got it back from the bore shop I just eyeballed the ring end gap looked ok, piston had good room too- stuck my thumbs on the skirts halfway up the bore and it clinked back and forth well. I had some trouble with the rings wandering off those locks on the piston, would I be able to get the cylinder on if the rings were over one of those position pins?

 

I'd say no. Unless you hammered the cylinder on.

 

the old piston got hot too, that's why I rebuilt it- maybe plugged exhaust ? I'm running 32:1 premix btw so oil isn't a issue

 

How about a comp reading?

 

comp guage is at my other shop, will pick it up asap

 

Textbook reasons for overheating are wrong plug or weak air fuel mixture. Blocked exhausts usually lower the max revs you can get, but you never know, some strange exhaust resonance could be the problem, so I would clean it out if you can.

 

What's the plug color?

 

I'm wondering if 318 is too hot.
Experts??