I had my doubts about my ability to salvage the engine from my 550, but I can honestly say I'm pleased with the results so far.
The bike has some work to go - a few electrical gremlins that can be chased down at my leisure, but otherwise it's running quite nicely.
One of my goals was to be able to kick start this beast - and by darned if I did that very thing this afternoon.
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It does kick start easily - far more easily than I would expect. Of course it died as soon as I released the kick start lever, but that's just technique I'm sure.
It runs nicely, and the more I run it the better it runs.
I do want to say thanks for the copious assistance I've gotten from you all.