Tony
I have a foot in both the XTZ660 & XT600 camps on this one:
660 Engine (I had an SZR660 for 4 years) - this was an annoying & regular problem, with draining the float bowl (or turning over for ever) being the only way to start the thing - especially in cold weather.
XT600 (4PT version) - Had for 6 months & fires up within a couple of spins every time.
I even put on a second set of carbs onto the 660 to try & eliminate the problem but to no avail.
Perhaps the likes of Klaus or DL may have a suggestion.
Cheers
Bish
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