First blowout

"tony R" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

Quite scary. Near the bottom of a hill with c. 50 kg. of trailer and kids behind me when the front
tyre went with a bang. No further damage thankfully. So now I need a recommendation for a good
solid commuting

tyre.

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Weight is not an issue and although it's a cheap bike I'm quite happy to splash out on decent
reliable tyres. The rim is a Weinmann Zac 2000, size
700c. The old tyre is a WTB Allterrainassaurus size 32/30. The tyre only

had

Quoted message said:

about 1000 miles use and the blowout happened at a point just above where the tyre is seated in
the rim. The hole runs lengthwise round the tyre for about 2 cms. and there are signs of wear for
about 5 cms. on either side

of

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the hole. So I'm wondering if maybe it was just a bad rim/tyre

combination.

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There is very little sign of wear elsewhere on the tyre. I'm fairly good about checking brakes for
rubbing etc. so I don't think that was the

cause.

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I've just noticed the rim is slightly out of true, maybe that contributed? Anyway, a good
commuting tyre please? I've used Conti TT and TT 2000 on my tourer and found them to be complete
[censored] to get on and off its Mavic rims. It now has Schwalbe Marathons which are showing
sidewall cracks

after

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c. 3000 miles. However none of these blew out or indeed punctured over

much

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so if they're the panels recommendations then fine. Thanks for the help, Tony R.

Blimey, bad luck! At least no serious damage caused, can't help with a tyre recommendation though as
I''m still getting through some Contis and you are right about the fit on rims!

tony R said:

snip]. The tyre only had about 1000 miles use and the blowout happened at a point just above where
the tyre is seated in the rim. The hole runs lengthwise round the tyre for about 2 cms. and there
are signs of wear for about 5 cms. on either side of the hole. [snip]

Bad break block alignment and a slightly off rim?

Phil

Andy Koppe said:

Still sounds like the brake rubbed through the tyre, especially as the load on the front tyre is
comparatively small.

That's well possible but some sidewalls fail on their own through normal use and poor
design/manufacture. We can't always blame the owner.

Sorry I can't recommend a suitable tyre with particularly good sidewalls Tony - as I'm not familiar
enough with wide 700c tyres.

~PB

"Pete Biggs" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Andy Koppe said:

Still sounds like the brake rubbed through the tyre, especially as the load on the front tyre is
comparatively small.

That's well possible but some sidewalls fail on their own through normal use and poor
design/manufacture. We can't always blame the owner.

Sorry I can't recommend a suitable tyre with particularly good sidewalls Tony - as I'm not
familiar enough with wide 700c tyres.

Thanks for all the replies. Yes it is a Rigida rim (but has Weinmann on the sticky label). As this
is the child towing, school run bike the brakes (including alighnment) are checked weekly - I'm as
sure as I can be that that wasn't the problem. However, closer inspection has revealed that the line
of wear gradually fades out in an arc with the highest point being where the blowout occured and the
lowest being at each side at the line where the tyre would normally be seated in the rim. I
therefore think that the tyre must have been badly seated in the rim with the rim putting pressure
on the wrong part of sidewall along this arc. I have to admit that although I try to be careful I
never thought to check for this sort of problem before (I will now though!). The tyre was as
supplied with the bike (no punctures up 'till yesterday) and to be honest I never looked at it
closely enough to spot this problem. Is this a feasible explanation? The LBS made my choice of tyre
for me - it only had one 700c x 32 tyre in stock a Schwalbe Marathon which I do like anyway - thanks
for the reassurance Andy.

tony R.

"tony R" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

It now has Schwalbe Marathons which are showing sidewall cracks after

Quoted message said:

c. 3000 miles. However none of these blew out or indeed punctured over

much

Quoted message said:

so if they're the panels recommendations then fine. Thanks for the help, Tony R.

I just got my first slow puncture after 6 months (not due to the sidewall cracks) in my rear
Marathon and today I've fitted the new Marathon Plus which looks like one solidly built tyre.
wiggle.co.ukv2 product detail.aspOpen ↗

Front tyre is Continental Contact which is still unpunctured (with no cracks) after 6months.

wiggle.co.ukv2 product detail.aspOpen ↗

Simon

tony R said:

The rim is a Weinmann Zac 2000, size 700c.

Nothing to do with your problem, but is that the same as a Rigida Zac 2000?

Quoted message said:

The old tyre is a WTB Allterrainassaurus size 32/30. The tyre only had about 1000 miles use and
the blowout happened at a point just above where the tyre is seated in the rim. The hole runs
lengthwise round the tyre for about 2 cms. and there are signs of wear for about 5
cms. on either side of the hole. So I'm wondering if maybe it was just a bad rim/tyre combination.
There is very little sign of wear elsewhere on the tyre. I'm fairly good about checking
brakes for rubbing etc. so I don't think that was the cause. I've just noticed the rim is
slightly out of true, maybe that contributed?

Still sounds like the brake rubbed through the tyre, especially as the load on the front tyre is
comparatively small.

The rim being out of true would explain why there were only 5 cms of wear. You wouldn't have noticed
anything unless you regularly inspected by turning the wheel with the brake applied.

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Anyway, a good commuting tyre please?

Schwalbe Marathon. Never had to change one before wearing it out.

Quoted message said:

It now has Schwalbe Marathons which are showing sidewall cracks after c. 3000 miles.

You can quite safely ignore those. The rubber coating on the sidewalls has no structural
significance, it's mainly there to protect the fabric underneath. As the rubber gets older, it tends
to crack. In how far that actually reduces its protective function I don't know, but anyway, you
only need to worry if the fabric itself shows any damage. But even then, in my experience, the tyre
still gives you a bit of a grace period.

Andy