Smart car trailer tyre pressures

Discussion in 'Tech/Mech General' started by Wicketter, Jul 1, 2012.

  1. Wicketter

    Wicketter Funster

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    We have a trailer we use for towing our Smart car behind our Bailey Approach 740. The tyres are marked 155/70R 12C, the trailer was from smart-trailers.co.uk. We think they should be around 4.5 bar, can anyone help with this please ?

    Many thanks.
     
  2. Brian and Jo

    Brian and Jo Funster Life Member

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    Hi there the tyre pressures on the 155/70/12 trailer tyres should be between 80 & 90 psi:thumb:
    regards brian jo and josh
     
  3. Wicketter

    Wicketter Funster

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    Tyre Pressures on smart car trailer

    Many thanks for the speedy reply. 90 psi seems really high for a load of 750k ( The Smart Car) we have just got back from a trip and checked the tyres which were 3.5 bar which seems too low ( they looked a bit squashy to me!) Sorry not very technical and I get confused between bars and psi's. 90 psi's would that equate to 6.2 bars ?
     
  4. chesterfield hooligan

    chesterfield hooligan Funster

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    :Smile: a lot of modern tyre's will have the tyre preasure on the tyre loaded and unladen :Smile:
     
  5. Brian and Jo

    Brian and Jo Funster Life Member

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    hi there yes that is correct 90psi is 6.2bar.the tyres on your trailer are hopefully not ordinary car tyres but are proper high pressure J-rated trailer tyres,manufactured to operate at high pressures, if you do not maintain the pressures they will get very hot when in service..also make sure that they have metal high pressure valves fitted to the wheels and not ordinary rubber car valves.
    brian jo and josh:thumb:
     
    Last edited: Jul 1, 2012
  6. Wicketter

    Wicketter Funster

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    Tyre pressures

    Once again many thanks. Really useful info, the tyres are fine but we will have metal tyre valves fitted now and than pump them up!:thumb:. We are off to France in 2 weeks so needed to get it sorted asap.
     
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  7. John & Joan

    John & Joan Funster

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    My Bantam Smart Car Trailer (Tyres 165R30C) has a plate attached which states 65psi.

    John
     
  8. pappajohn

    pappajohn Funster Life Member

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    If anyone should know it's Brian (brianjojosh).

    he's a respected tyre dealer/fitter.
     
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  9. Brian and Jo

    Brian and Jo Funster Life Member

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    Hi john,yes in a 165/13 65psi is correct but a 155/70/12 J rated trailer tyre is designed to run at between 80 & 90psi.it is designed as a semi low profile tyre with a very strongly constructed sidewall,hence needing the high pressure,and can only be fitted to trailers.the tyre on your trailer can also be fitted to some small vans and some caravans:thumb:
    brian
     
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