Bike Tyre - Max Weight & PSI

Mark1889
Mark1889 Posts: 19
edited May 2017 in The workshop
Me again!

Thanks for all the help on the various threads (inc ones where I didn't post, but the thread answered a related question!)

I use 700x33c tyres on my Cyclocross (ultimately I may soon change these, particularly over summer).

The bike was second hand and came with tyres saying max load 75kg (I'm 85kg so I'm assuming this is per tyre - although the rear may exceed this esp with saddle bag, me and rucksack.

Also it says max PSI 75...

I've had three punctures in three 20mile rides... do I need new tyres?!

Comments

  • Yep, the bigger the tyre the less PSI required. And yep, 75kg per tyre. Are you getting pinch flats or from foreign bodies? Is there anything on or in the rim itself that could be causing the flats? What's tread wear like?
  • Mark1889
    Mark1889 Posts: 19
    Thanks!!

    It seems to be from foreign bodies (and I'm always checking the tyre when replacing the inner tube for loose thorns/glass/whatever it may be!

    Tread is great although just noticed that I've just put my tyre on the wrong way (I mean literally just now) is that a big deal? Guessing it must be as they tell you which way it's meant to rotate for a reason!!

    So yeah, me blowing it up yo 80psi may have been the issue
  • cougie
    cougie Posts: 22,512
    Same tyre or different ones ?
    Three flats in three rides would have me ordering new tyres.

    Schwalbe make some tough marathon plus tyres. They aren't the fastest tyres but you'll not be stuck at the side of the road either.
  • roger_merriman
    roger_merriman Posts: 6,165
    Mark1889 wrote:
    Thanks!!

    It seems to be from foreign bodies (and I'm always checking the tyre when replacing the inner tube for loose thorns/glass/whatever it may be!

    Tread is great although just noticed that I've just put my tyre on the wrong way (I mean literally just now) is that a big deal? Guessing it must be as they tell you which way it's meant to rotate for a reason!!

    So yeah, me blowing it up yo 80psi may have been the issue

    A tyre will generally rupture if over pressure, and not to be useable after!

    CX tyres do tend to be fast light, and fairly puncture prone, which tyres do you have?
  • Mark1889
    Mark1889 Posts: 19
    cougie wrote:
    Same tyre or different ones ?
    Three flats in three rides would have me ordering new tyres.

    Schwalbe make some tough marathon plus tyres. They aren't the fastest tyres but you'll not be stuck at the side of the road either.

    Hey - thanks!

    It was two on the back and one on the front, but yes I have not replaced the tyres.

    Ultimately I do think that changing tyres sooner that later is a good shout. I never race..! :)

    Thanks for the tip, appreciated

    Mark
    A tyre will generally rupture if over pressure, and not to be useable after!

    CX tyres do tend to be fast light, and fairly puncture prone, which tyres do you have?

    Hey Roger - thanks for the comment!

    Here is a link to the tyres that I have: http://www.velobikes.co.uk/4458/product ... oCjZDw_wcB

    Here is a link to my bike: http://www.tredz.co.uk/.Giant-TCX-SLR-2 ... _84055.htm

    As I say, I am mainly a commuter with a few leisure cycles - 20 mile round trip for a pub dinner in the evening w/the Mrs or a 35 - 60 miles cycle on a Sunday/Bank Holiday morning.

    I was on my road bike this morning but this week I will try my newly installed (tread going the right way) inner tubes and see what happens..!

    Mark

    More generally - Do you you how I find out what the maximum and minimum widths are suitable for my rim? I can't see any text anywhere apart from 960x20 on the rim tape... I tried (and failed) to google what that meant.
  • kajjal
    kajjal Posts: 3,380
    To give you a comparison my bike currently has 33mm tracer pro tyres on as I do a lot of off road riding in the drier months. This is mainly for the grip from the knobbles and the comfort from the bigger air volume. They are rated from 45 to 90psi. I weight 100kg.

    A few days ago I accidently went out with 40psi in each tyre. They help up fine off road and I set some PB's. I normally have them at 60-65psi , higher pressure in the back wheel and have no problems with punctures etc.

    In the winter when on road I ride 25mm roubaix pro's at about 90 PSI and so far no punctures at all. This is probably pure luck
  • Mark1889
    Mark1889 Posts: 19
    Kajjal wrote:
    To give you a comparison my bike currently has 33mm tracer pro tyres on as I do a lot of off road riding in the drier months. This is mainly for the grip from the knobbles and the comfort from the bigger air volume. They are rated from 45 to 90psi. I weight 100kg.

    A few days ago I accidently went out with 40psi in each tyre. They help up fine off road and I set some PB's. I normally have them at 60-65psi , higher pressure in the back wheel and have no problems with punctures etc.

    In the winter when on road I ride 25mm roubaix pro's at about 90 PSI and so far no punctures at all. This is probably pure luck

    Thanks! That's helpful :)