Tubes, How hard?

[JABS]

I am sure this has been covered before, but I can't find a thread!

The question is, how hard should my tubes be? They are black and are very susceptible to heating in the sun. I find they are really hard in the heat of the day, but quite floppy in the early morning.

Should I pump up when it is cold and relieve the pressure when it is sunny?

We went back to Cowes late at night recently and they were so floppy I was concerned about damage?

Would appreciate input, please.

Thanks!

Tony

[Limey Linda]

Yup, have same problem " allways floppy in the morning"

[Red Fox]

I have a pressure guage that came with my Zodiac. I use a footpump to inflate and when it is difficult to push down, that is usually the right pressure according to the guage. The tubes feel hard. In the heat they do get firmer and in the cold they go softer but i recon on the water they are in contact with 15-18C so they should be fine even on a hot day. I have heard of pressure relief valves but dont use them so cant comment on their effectiveness. i wonder at what pressure they release air? in the UK that will not happen that often! Still raining in Scotland and not so ruddy warm!

[JABS]

Originally Posted by Red Fox

I have a pressure guage that came with my Zodiac. I use a footpump to inflate and when it is difficult to push down, that is usually the right pressure according to the guage.

Do you have any idea what pressure that is??

Thanks

[codprawn]

Originally Posted by Red Fox

I have a pressure guage that came with my Zodiac. I use a footpump to inflate and when it is difficult to push down, that is usually the right pressure according to the guage. The tubes feel hard. In the heat they do get firmer and in the cold they go softer but i recon on the water they are in contact with 15-18C so they should be fine even on a hot day. I have heard of pressure relief valves but dont use them so cant comment on their effectiveness. i wonder at what pressure they release air? in the UK that will not happen that often! Still raining in Scotland and not so ruddy warm!

My RIB has pressure relief valves and you would be suprised how much air they vent off. I have seen RIBs without them pop the seams.

Personally I believe tubes should be as soft as you can get away with without them flopping all over the place - it's much easier to burst a balloon blown up as hard as you can than one that's only 1/2 inflated!!!

[Neil Harvey]

Tony,

I think I read somewhere about 2-3PSI is about right, but can't remember where, sure it was on here.

Do you have pressure relief valves? I find that after a hot day, sometimes in the evenings etc my tubes are soft, as the relief valcves have let air out. Hence need topping up for a late run back or early in the mornings. I ran with softish tubes once, too soft, ride changes and sure not good for boat if you keep doing it.

KR

Neil

[Red Fox]

Originally Posted by JABS

Do you have any idea what pressure that is??

Thanks

sorry no, it just has +/- and a green zone for correct. So how do the pressure relief valves vent? Do you set them to go off at a certain pressure? If so what is it?

[jyasaki]

My Polaris (hypalon) has a pressure of 2.5 psi max.

My buddy's Avon (hypalon) uses closer to 4 (I think; that's what they told me.)

My other buddy's Zodiac (PVC) runs around 3.5, as I recall.

YMMV.

jky



My old Achilles SIB (also hypalon) ran 4 to 4.5 psi.

[walruz]

My Searider still has Avons original plate which recomends 2-3 PSI.

Ian

[limeydal]

well indirectly!
My XS-Rib was fitted with pressure relief valves, as it get toasty quite often over here in Sunny California.
Only problem is, they do their job and vent off excess,but then when it cools down at night ,the tubes tend to get the "floppies".
So its usually a little top up next morning before it heats up,just so its not flopping around on the trailer.
3.5psi seems good
Luckily had an old low pressure /high volume spray unit that puts out about 10 psi. So I made up an angled inflator adapter from some PVC , to go on the end of the spray hose , which is great for quickly topping up the tubes before leaving home.
cheers Dal