Odd punctures - two in one run!

[PaulH]

I took my Elan for a run yesterday; for my mental health and to get some running in miles done. The Elan ran well.
So that was all very lovely until I got a puncture:

I found a safe place to put the spare on, so all good again. About a couple of miles from home the handling felt a bit odd. A quick check found a rear tyre only half inflated so I got home straight away. Only just made it home:

How odd is that. I've checked the tyres for obvious signs of puncture and can't find any. I'm thinking the inner tubes may be the problem. I'll post what I find when I get them repaired. Hopefully I haven't trashed the tyres.

I also had a go with my new GoPro camera. I've had some good advice on Facebook (thank you Colin) about reducing the wind noise, so hopefully I can improve the sound in the future. Here's a link to the video:
https://youtu.be/_RS0ps539fQ
Paul

[bitsobrits]

Wondering why you run tubes?

[69S4]

Is there a secret to running std wheels tubeless? I thought they were designed for tubes?

[bitsobrits]

No secret, just ignorance. Not knowing any better I've run the factory wheels without tubes since my first Elan in '79. I am aware there are no bead safety ridges with the stock wheels. Those ridges help keep the tire seated with a puncture or very low pressure, so I've alway been vigilant about tire pressure. My S4 coupe was my autocross car for a few seasons even. Not saying you should follow my lead here. Only sharing my experience.

[denicholls2]

Not running tubes is likely a lot safer unless you've somehow managed to find modern tires that are "tube safe". Which may explain two flats without tire punctures on one outing...

This side of the pond, every tire I've bought since the Seventies has a disclaimer not to use tubes on the sidewall.

[MarkDa]

This may sound like a silly question but your tyres are tube type aren't they?
A tubeless tyre may well have ridges inside that can wear through tubes and lose air without signs of punctures.
Might also explain why failed at same time if you replaced all together.
You could also have just run over a "spike" with both wheels - just reviewed photos and tyres on opposite sides!
So my money is on tubes in tubeless - which is a less safe option than tubeless alone.
The Michelin XAS was-is a tubed tyre as were some other tyres of the period.

It's your choice of course but I'd be inclined to use a softer faced hammer on the spinners either a heavy hide or nylon face Thor type - or lead as original fit are available.

[USA64]

If I recall correctly the wheels were designed for tubeless. The safety ridge had not been invented yet.

[TBG]

Liked the video - can't wait to see the full power run later on the same roads!!

I think Elan owners are getting older.....................

[oldelanman]

If I recall correctly the wheels were designed for tubeless. The safety ridge had not been invented yet.

You are correct.
The Workshop Manual lists tubeless tyres among the options of the period .... it also warns to fit the appropriate tube with radial tyres
I believe the safety ridge or hump ledge was introduced to prevent the tyre rolling off the rim when flat or under-inflated.

[PaulH]

It's your choice of course but I'd be inclined to use a softer faced hammer on the spinners either a heavy hide or nylon face Thor type - or lead as original fit are available.

I agree, I've just got a softer hammer (hide). I've been using a block of wood to cushion to blows.

Paul

[PaulH]

Liked the video - can't wait to see the full power run later on the same roads!!

I think Elan owners are getting older.....................

I'm looking forwards to more revs

I'm not sure how to take the comment about the age of Elan drivers. Do I look such an old sod

Paul

[ericbushby]

I`m getting older thank goodness, I don`t want the process to stop just yet. !!
Eric in Burnley

[PaulH]

I have the answer why I got two punctures in the same run. There was a foil label on the inside of each tyre. The label has moved between the tyre and inner tube and damaged and eventually punctured the inner tube. Lucky I didn't have four punctures
You can see the remains of one of the labels here:

and the damage on the inner tube matches the size of the label:

Who'd have thought

Paul

[sprintsoft]

Hi Paul,

Thank you for taking the trouble to share the details, from the pic of the inner tube it looks like a defined series of letters etched in the rubber- is that just an illusion?

Thanks
Iain

[MarkDa]

The label was exacerbated by those internal ridges - I'd say those tyres were not designed to be run with tubes.
What do the tyres say? Any tyre that requires a tube will say so on the outside
If you want to use tubes (which are far from necessary) then you must buy tubed tyres.
Using tubes is only safer (as you have found out with two flat tyres in a few minutes) if the tyres are designed for them.
In terms of safety tubed tyres are more susceptible to blow outs because air will leak out around the valve when the tyre-tube is penetrated. A tubeless tyre will seal around a nail for example.

Getting tubed tyres is actually quite hard nowadays.
In period the rim profile was regularly being used on many other cars with tubeless tyres.

See how smooth inside of XAS is
https://images.app.goo.gl/zwEzbM8Dn43Az3gB7

Ditch the tubes I say.