Tyres suddenly deflating?

Spins

I've got Vittorio Rubinos on my wheels. I've always had them pumped up to at least 130psi. Last night I had a club time trial and decided I'd try a higher pressure and pumped them to the max mark 150psi. Everything went ok for tt but last night as i was watching tv, suddenly one of the tyres just sssssssss deflated. Then this morning, the other went. Is this normal at such a high psi or should I just consider new tyres? I don't have racing wheels (yet) so any tyres I'd get would have to be suitable for training and racing.
Thanks!

stuf

Spins wrote: »

I've got Vittorio Rubinos on my wheels. I've always had them pumped up to at least 130psi. Last night I had a club time trial and decided I'd try a higher pressure and pumped them to the max mark 150psi. Everything went ok for tt but last night as i was watching tv, suddenly one of the tyres just sssssssss deflated. Then this morning, the other went. Is this normal at such a high psi or should I just consider new tyres? I don't have racing wheels (yet) so any tyres I'd get would have to be suitable for training and racing.
Thanks!

rim tape probably gave way with the high pressure and you punctured on a spoke nipple

happened to me when I build my first wheel and forgot to put the rim tape on - doh!

niceonetom

150!!!??? we're talking clinchers here right?

not necessary and not safe. Sounds like something just let go under the pressure - no big deal, but hardly surprising.

DirkVoodoo

I have 25mm Rubinos, pumped up to 100-110 PSI. Even on 23mm the most I would pump to is 120 PSI (for clinchers).

Lumen

I've read that rolling resistance does not change much once you're in the ballpark of the recommended pressures, so you're achieving nothing positive anyway.

Spins

Even tho the max mark on the actual tyre is 150 psi???
120-130 psi max ye reckon?

DirkVoodoo

Yes, the maximum is 150, as in the maximum safety limit, as in "your pushing it".

Pick somewhere between max and min, it's nice there.

Lumen

Spins wrote: »

Even tho the max mark on the actual tyre is 150 psi???

Your tyre didn't fail.

rottenhat

DirkVoodoo wrote: »

Yes, the maximum is 150, as in the maximum safety limit, as in "your pushing it".

Not in these legal-minded times - if a tire says max 150, it can almost certainly take 160-170. No sane tire manufacturer would post a max that was "pushing it" - it's a law suit waiting to happen.

That said, 150 sounds pretty high to me - I bet you could play those things like a drum.

rottenhat

Lumen wrote: »

Your tyre didn't fail.

That's a very good point.

niceonetom

1) My rubinos are rates for 145psi. I really wouldn't want to excede this and ride around waiting for them to go bang. I usually keep em at about 110 for general use - i might go a bit higher for speed. Like 120.

2) Rims have a rating too. My open pros are rated up to 140 (I think). It sounds like that's what let go in your case. Have a good look for any sign of cracks, though stuf is probably right about it being a spoke hole. Are they quite shallow rims?

3) Higer pressure =/= lower rolling resistance.

tunney

Lumen wrote: »

I've read that rolling resistance does not change much once you're in the ballpark of the recommended pressures, so you're achieving nothing positive anyway.

Ah but it does....................

But not how you think. In a nut shell on Irish roads anything over 140 has the opposite than expected effect and *increases* rolling resistance. On continental roads you could go higher.
(Obviously this is a generalisation).

I wish someone had told me this before I did my first race on my zipps on manky Limerick roads at 240psi. Talk about knacker-destroying.

Spins

stuf wrote: »

rim tape probably gave way with the high pressure and you punctured on a spoke nipple

Does that mean I need new rim tape too?

Spins

Lumen wrote: »

Your tyre didn't fail.

True. Never thought of that. Thanks.

Chips Lovell

Yes, while tyres may be rated to high pressures, rims and tape may not.

I'd only whack tubs up to that pressure and only in limited circumstances. I've tried 160psi and it feels great on good roads but way too jittery on the bad ones.

stuf

Spins wrote: »

stuf wrote: »

rim tape probably gave way with the high pressure and you punctured on a spoke nipple

Does that mean I need new rim tape too?

probably yes - although you may have had a pinch between tyre and rim which didn't show up until you got to such a high pressure.

take it apart and check the rim tape for loose spots - it's not expensive anyway