Yes any high performance engine is more of a pain to break in then what most run a sports engine. Preheating the engine helps a lot. I wish I would have gone with a starter box but got the pull starter and was really a pain. Now after broke in no problem. In order to keep the front wheels on the ground with my TZ most of the time I had to gear it up to 16 CB and 47 spur. If you think it is fast now wait till you get about a gallon on it.
Glade to help anytime.