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hydroplaning
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some formula like the psi of the tire times 9 = speed knots you have to
travel in order to hydroplane... now i know this formula being based out of
NASA of course would be centered around smoother tires like those on a space
shuttle, not a dirt bike.... so in theory if a spode were to fill his tires
to 10 psi then travel at 90 knots or 103 mph so i would have to be going
100+ mph on a bike to get accross the river without touching bottom... now
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I have seen guys doing water crossings on bikes in some of the jump
videos. They looked to be going about 50 or so. And yes, kwads do way
better on water.
I run my pickup tires at 50-55 PSI, just so I don't have to worry about
suck things.
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if i took a quad with 4 psi tires i'd be traveling 42mph to achive
hydroplane speed... thus a quad river cross might be easier than a bike
crossing yet the notion of the front loosing plane and coming to an abrupt
halt has prevented me from trying this sillyness i do wonder how it would
work out... (where's guido when you need him)
john
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Another important variable would be the contact patch area....and
probably its relationship with the overall weight of the vehicle. Quads
are generally heavier than bikes, but their contact area would likely
more than offset the additional weight.
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Some quads with oversized tires will nearly float. I've seen some where
they put on really big tires or duals all the way around that would
float... that's got to be a big plus if you want to skim a deep body of
water. :)
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Hopefully they don't turn turtle in the middle......
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I imagine that this would be far more important than tire pressure when
comparing different vehicles.
NASA probably considers tire pressure since all other variables
[vehicle weight, contact patch area, landing speed, etc.] would not
vary that much with respect to the shuttle.
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Mmm I think the dynamics will be different for 'shallow' hydroplaning
(like a car or bike or shuttle on a road/runway) and 'deep'
hydroplaning (crossing pond, crick, etc).
Like a plane up in the air a bit, or one using ground-effect.
I've seen some vids about of loonies on bikes crossing a pond, now
where the heck was that?
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Do you not recall my hydroplane adventure across the beaver pond
at the Dam a while back? Scared the bejeezus out of that family!
Me, too, after I realized how deep it was...
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