Tyres again

[thosoneill]

My Abbey owners service handbook states that I should run 185/70/13/86 tyres - my caravan weighs 779 unladen and 985 fully laden - just hoping that the handbook tyre spec is up to the job

 

[otherclive]

My Abbey owners service handbook states that I should run 185/70/13/86 tyres - my caravan weighs 779 unladen and 985 fully laden - just hoping that the handbook tyre spec is up to the job

Well just check it against your tyre load indexes there are lots of charts on the web that give load index numbers and the load carrying spec for the tyre. If any concerns do what others do and go for tyres if a higher load index. My Bailey had tyres that took a combined load of 1420 kg. The vans MTPLM was 1400 kg. So I uorated the tyres.

 

[Woodentop]

To be correct the tyre is 185/70R13 86(letter) where the missing letter is the sperd rating - often H or N on a caravan.
86 is 530Kg so two tyres will take 1060Kg. That is less than 10% overload capacity so if I were changing tyres I would go for a 93 load index; there are only three load indexes in your tyre size - 86, 93, and 106/104.

 

[thosoneill]

To be correct the tyre is 185/70R13 86(letter) where the missing letter is the sperd rating - often H or N on a caravan.
86 is 530Kg so two tyres will take 1060Kg. That is less than 10% overload capacity so if I were changing tyres I would go for a 93 load index; there are only three load indexes in your tyre size - 86, 93, and 106/104.

Thanks for the helpful response - you do wonder why the handbook quotes an 86 load index - 93 seems a better alternative

 

[ProfJohnL]

To be correct the tyre is 185/70R13 86(letter) where the missing letter is the sperd rating - often H or N on a caravan.
86 is 530Kg so two tyres will take 1060Kg. That is less than 10% overload capacity so if I were changing tyres I would go for a 93 load index; there are only three load indexes in your tyre size - 86, 93, and 106/104.

Thanks for the helpful response - you do wonder why the handbook quotes an 86 load index - 93 seems a better alternative

Hang on a minute, Why do you need to go up to the next higher load rated tyre when the one specified is already 10% over the caravans MTPLM????

Let me explain my thinking. First of all there is nothing wrong about using a tyre with a higher load rating, but the question is why choose one when the specified tyre is already more than adequate?

I'm not a tyre expert, but when a tyre is given a load rating, you should be able to expect it to run with that load until it wears out. We also know that when a vehicle is in motion, the road condition and changes to speed and direction create some quite startling dynamic loads which impose greater loads on the tyre than the static load. Tyre manufactures are well aware of this and design and build their tyres to accept the maximum static load, plus the range of operating loads the tyre will encounter.

Consequently I can see no benefit of ignoring the specified tyre and going for one with a greater static load rating.

 

[Hutch]

With the state of the roads in the UK with potholes etc, I think upgrading the tyres to the next load rating might be an advantage just for the safety point of maybe not being able to avoid the potholes.

 

[Thingy]

just for the safety point of maybe not being able to avoid the potholes.

Referring to another current thread. Thats what ATC is for, swerving round them at 60mph. B)

Seriously though, it cant hurt to have a bit of redundancy.