Sucks that I missed it the first time.
Good for me that it is working fine.
Lucky the throttle was just under a little tension instead of 'open' like your 250 was. I would have to imagine there would be some kind of damage done somewhere stopping a 500 with that method.
I always check the throttle 'snap back' before firing up but obviously missed that it was 'not quite' all the way closed at rest or at least under a bit of tension.
I remember I was in a hurry to get it started because I 'had to get going' which is always a recipe for a disaster.