Trials Tire PSI - Page 2

 Depends a little bit on the tire, the IRC brand you could run less than you
would a Michelin tire.  Michelins for me would a little more because I swear
the sidewalls are slightly softer.  I run Dunlop, rear is tubeless, I weigh
over 240 I run 5lbs in rear, I like 5.5 in front.  the really great riders,
ride with less, !!! and they weigh less than I do.  if you weigh in under
200 probably 4lbs in Dunlop/IRC 4.5 with Michelin.  when it is wet and
slippery I let more air out!  I have ridden with 4lbs in a sloppy trials.
The thing is, if you goto 4 lbs like some do, then you just don't race down
the trails between sections banging off the rocks, you are more careful in
your path selection.  If you run tubes, then you might run a .5 lbs higher
pressure just to keep from pinching tubes!

Here is an observation from 30 years on the trials scene, and training new
riders.  right off the bat, flatter tires feel funny. so you start with no
more than 6lbs to ride.  This means your not going to race down rocky roads!
after you get just a tiny bit used to it, low pressure will feel right and
high pressure feels goofy likea beach ball.  in winter the bike (even not
going 10 mph all day) will need to let air out after the 1st loop!  air
expands tires will generate heat when riding even when weather is barely
35-50 deg... lol who da thunk it?

 
Great.  Thanks for the replys.  My next question is what size rim are
you using?  I am having a problem maintaining the tire bead on a
Dunlop D803 when under 12 PSI.  I am using a 1.85 excel rim.

 As far as my rims, Goto gasgasusa.com look for specs, I cant I'm at work,
anything fun related is blocked..

I've been on the 300 pros, since 02.  I currently have in the stable, 2 06's
and one 09 raga prototype pro.  course that 09 one has a nicer rim on it,
like montessa's been using.

Chris, did you see the earlier thread, are you dealing with a new tire?
if old/ used tires then Hmmmm...   im thinking how old?  if old, someone
might have mangled it off the rim.  Yes you can ruin the beads...

FWIW, they are a beyotch, just like cars to unseat and seat the beads on
newer tubeless rim/bikes.  if you are using tubeless tires on older 'tube
type' rims, make sure you have a FAT tube.  the tube is 19 x X.XX in specs
19 means rear diameter of rim, (wont say cause brain doesn't know what the
x's are) but you need tubes that are like 3.50 or 4.50 that is like fatness
or cross sectional diameter or ratios of the tubes...  and 3.50 mightbe
bicycle sizes stuck in my head for 20 inch BMX bikes.  so check, but they
are the common tube even for motocross tires, so on second thought, hmmm  I
don't know.

the tires, I've placed them right now, on 2 Honda TLR's (1974 models) and 3
RL Suzuki's also 70's models with stock rims (tube type), they fit fine with
5lbs of air...  I'm thinking something is not right with your setup, or
tire...





Great.  Thanks for the replys.  My next question is what size rim are
you using?  I am having a problem maintaining the tire bead on a
Dunlop D803 when under 12 PSI.  I am using a 1.85 excel rim.