This article is from the Mountain Biking FAQ, by Vincent Cheng.
-Pop a front wheelie and land so that your front tire clears the log.
-Quickly level the pedals and shift your weight forward.
-Your back wheel should roll right over the log.
Rik Allen [richard@prl.research.philips.com]
Or, when riding fast with toe clips, just hop the whole thing, bike
level. Works at speed, up to about 1' depending on ability. Make sure
you have space to comtrol the speed after the jump. Get it wrong and
your wheels might be history though.
When racing, if the log is too big to cross with 2H, you might be better
off getting off the bike. A good cyclocross rider will unclip before the
obstacle, swing one leg over behind the other, then when you get to the
obstacle, one or two strides will get you over it. Then a controlled
lunge back into the saddle (practise this _slowly_ first) and you are
off again, never having dropped below 15mph.
(author's note:read teh disclaimer again before doing any of this, I'm not
responsible for your injuries or damage to your equipment)
 
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