Originally Posted by H5487
But I'm not 100% sold on the Cox just yet. The practical side of me reminds me that I've already got three potential candidates bought and paid for.
Which NORVEL do you have? Is the cylinder silver or slightly gold colored with notches for the cylinder screws or is it black with holes to access the cylinder screws.. Does your carb have retainer screws to hold it in the crankcase? There is a NORVEL faq sitckied at the top of this forum with pictures to help you identify your engine. NORVELs are not necessarily a beginners engine and can be difficult to start initially. They also take quite a bit of time to breakin. I do not support the later model recommendation to cold flip the engine until the top end pinch is relieved. I believe that this approach just causes premature wear. I generally use heat (monokote gun) to preheat the cylinder for initial starting. When your engine does start, get it up to running temp quickly --- these engines are not set up to run sloppy rich and cool, but rather run it at a rich two cycle during the breakin period.
My ranking would be the NORVEL first --- it's light, a horse and well made. The TT07 is heavier, is ranked somewhere between a good .049 and a highend NORVEL .061, but most of the .07's are well behaved, have good throttling and are fairly consistant runners.
The AP's are Chinese knockoffs of the early model NORVELs without the fit. Most have a reputation of being short lived. Some can be made to run; some are junk.