Do rotoflex couplings deteriorate in storage

[pimkeirle]

I have a pair of "new old stock" rotoflex couplings in a box in my garage, they've been there at least 5 years, but they look OK to my un-tutored eye. Has anyone any experience of using old (but still with the original metal band and unused) couplings? The couplings on my Plus 2 have been on there for 8 years now and the rubber in them is definitely showing signs of perishing, hence my intention to replace them, but new ones are c.£120 each, so if my stored ones are OK it's obviously tempting to use them.

[USA64]

I've asked this previously and gotten no reply. Also recently about the oil filters (paper element, rubber gasket). An additional problem is the "new" ones, not being dated; may be years old themselves. Tires are 8-10, I have been offered eight year old tires as new.

[StressCraxx]

They should be usable as long as they have not been exposed to UV or ozone for long periods (higher voltage electrical equipment with corona discharge).

How do your old ones look? If they are not fractured when you rotate them at full droop, they should be ok. Do check the bolts are still tight. Loose bolts will fail from fatigue and then the donut fails.

[Billmack]

I have seen rotoflex fall apart in storage

[Andy8421]

Rubber does deteriorate with age:

https://www.walker-rubber.co.uk/knowledge-hub/the-ageing-of-rubber-366

Modern rubber seems worse. I don't know the cause - perhaps the additives used these days are limited because of 'elf and safety.

I have a low mileage mini with tyres that received an advisory on its MOT test for cracking on tyre sidewalls - the tyres are less than 8 years old. I have a tyre in the garage that is a spare for my Standard that is at least 50 years old that looks as good as new.

[Donels]

If you have 8 year old ones that are perishing surely the 5 year old unused ones are good for at least 3 years!

I would fit them and inspect annually.

[UAB807F]

I would also fit them but inspect them on a regular basis - 1st or 2nd run, couple of weeks, monthly ? Nothing after a couple of months and I'd expect them to last as long as any ever did.

The link posted is a good description of how rubber deteriorates and you can see that the big problems are sunlight and temperature. Inside a box in your garage will avoid sunlight and most probably temperatures high enough to cause deterioration. The failure mechanism will be from the surface inwards, so if they look ok, they are worth trying.

If there is any damage it's likely to be obvious with surface cracking after fitting/being driven so regular inspection will pick that up long before it gets to a critical stage where the bulk of the rubber is failing.

Brian