Originally Posted by
estamm
A few of you mentioned "changing to a nova carb" is this a known issue?? can someone show me the link if this has already been covered. It would appear that this engine can run well with a variety of plugs as long as they are on the hot side, so I can rule that out. Also the engine I am refering to is the newer version of the B7pro. Do the problems I described during break-in sound familiar to anybody?? I am wondering if I should send it back as defective or keep going and see if it starts to run better. In my experience I have never seen an engine run this poorly during break-in, Im wondering if I got a lemon.
All the things you describe sound fairly normal in my experience. The pinch is very soft on most of the engines I've seen, it doesn't seem to effect compression too much though. Most of the guys saying "it's still got heaps of pinch" probably still have the plug in....
The carbs are a bit hit and miss on them, one thing I found they are quite prone to is stretching or even breaking the main needle holder that holds the fuel banjo on. I had one do all sorts of screwy things trying to run it in and I traced it down a split needle holder. Be very gentle doing them up!!
Good luck...