Sounds like the OS TZ Speed Spec II I broke-in last year.... it will be hard to start... must use a heat gun for the first few tanks... and MAKE SURE you change out the conrod after you finish your break-in! I've use a hair-dryer... just don't tell the wife!

Also..... you may need to lean the engine to start it initially from the factory settings.... but if you run it a little rich the oil in the fuel will assist in cranking it over for the first few times before it fires... Keep the heat on it and use a flat-head screwdriver to spin the flywheel if it gets stuck...

take your time