You have to do it a bit, if you've got time to blip the throttle you're not trying hard enough. Mechanical sympathy after my Brands practice seize saw me being careful in (what remained of) practice. But on race day when the red light went out and Leigh made those 10 extra horses count on the drag to the first corner, forget it!

Most clips you see of on track 2 stroke action have some lack of concern for the life of the engine, all these guys are just letting it spin on the downchange;
http://www.youtube.com/watch?v=Ed-GaGcMp2U
http://www.youtube.com/watch?v=HIpDy2B_pvg
http://www.youtube.com/watch?v=SrKpgAczN8c

And somebody hellishly quick round Mugello
http://www.youtube.com/watch?v=SyYbWQuxNyo
that's within a couple of seconds of Lorenzo's outright 250 lap record, he's not got time to blink, let alone worry about crank life!
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