trials_uni said:well theres a big difference between 165 ans 235 and not much of a diff
between 17 and 22. plus ive seen people who are like 170 running
pressures of like 30-40psi..thats why i was wondering.
There is a big difference between the -difference- of the numbers which
is unimportant. The -ratios- of the numbers are quite close. The
contact patch area of the tire should be very close to the same in both
cases.
I weigh in at 195 and keep my trials tire pressure so I just don't
bottom it as I precompress for a big hop. This is about 18 psig for me.
I am bottoming my tire on four foot drops. I don't care. Trials
unicycles are for beating up. I have been riding mine with a broken
spoke the last three times out.
Your idealized contact patch area is just that, an area. The pressure
of your tire is given in units of force per unit area. Your weight is
given in units of force. The quotient of the two yields a number with
units of area. If you weigh 235 pounds and your tire pressure is 22
psig then about 10 square inches of your tire would -ideally- being
making contact with the pavement. Tires are not ideal and are not
perfectly elastic.
Psig stands for pounds per square inch gauge which is the pressure
-above- the local atmospheric pressure. Psia stands for pounds per
square inch absolute which is the pressure compared to vacuum, zero,
free space. Psi is commonly used to indicate psig.
Jump, drop, scrape your trials uni and have a ball. Experiment with
different pressures. I will eventually pinch flat my trials tire. You
will too if you take my advice. Gerblefranklin is an accomplished
trials rider who will disagree with my assessment entirely. He differs
from me. He's talented, I'm not.
--
harper
-Greg Harper
B L U E S H I F T
*jc is the only main man. there can be no other.*
This is still my nth post....*AWESOME!!!*
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