Tyre sizes

[stuarttunstall]

Hi

Now I know this is a VERY stupid question .... My Scott Sub Cross 10 is fitted with Schwalbe Smart Sam / 700x42C / 50 TPI tyres.... Can someone explain tyre sizes? I have done a search and it seems that 700x42C is an odd size... I can seem to find other 700x4x tyres...

When the time comes for tyres what would I actually look for, would it be 700x42C

Stuart

 

[Jenkins]

You don't have to stick with the exact same width when it comes to replacement or upgrade, only the diameter (the 700 part). Depending on the clearance, you could go up a bit for comfort or perhaps down a bit if you fancy something a little narrower. Not knowing the rim width of the wheels or the clearance on the frame, you could have the option of looking at tyres on a range between 700 x 32 up to 700 x 48.

 

[Spiderweb]

They are 700c x 42. 700c refers to tyre size, 42 refers to 42mm the tyre width.

 

[stuarttunstall]

Thanks for the replies... I would say I could get wider tyres in the frame, maybe 45's... The only reason for my question is when looking at tyres 700 x 42 seems unusual, most do 40 or 45 ... I can see the odd 42 not not many... unless I am looking wrong which is most probable lol

 

[vickster]

Thanks for the replies... I would say I could get wider tyres in the frame, maybe 45's... The only reason for my question is when looking at tyres 700 x 42 seems unusual, most do 40 or 45 ... I can see the odd 42 not not many... unless I am looking wrong which is most probable lol

They look like very chunky tyres, is the bike mainly for riding off road? If on road, you'll roll better on slicker narrower tyres and you'll want the suspension locked

 

[stuarttunstall]

They look like very chunky tyres, is the bike mainly for riding off road? If on road, you'll roll better on slicker narrower tyres and you'll want the suspension locked

The bike is a hybrid so for both really although I will only use on-road...

 

[vickster]

The bike is a hybrid so for both really although I will only use on-road...

Right, definitely look at different tyres. Says it has a lock out so you'll want that on or it'll be very hard work on the roads

 

[stuarttunstall]

I was going to ask that, I presume you mean the lock out on the front forks? If so yes it does I will try locking that tomorrow morning and see how it goes .

 

[vickster]

I was going to ask that, I presume you mean the lock out on the front forks? If so yes it does I will try locking that tomorrow morning and see how it goes .

Yep otherwise you'll just bounce along especially with those big fat tyres!

 

[stuarttunstall]

Thank you, will give that a try

 

[Pale Rider]

The 50 TPI marking on your tyres is interesting for the tyre anoraks among us,

TPI is threads per inch and refers to the density of the carcass.

The interesting bit is all Schwalbe tyres sold as retail are 67 TPI - a more dense carcass and something Schwalbe push in their marketing.

Your tyres are a slightly cheaper original equipment version of Smart Sam.

Does this matter?

No, not really, although they will have a bit less puncture resistance.

As a comparison, some cheap and nasty tyres from other makers will be under 40 TPI.

 

[stuarttunstall]

That is interesting... thank you..

 

[Pale Rider]

Interesting?

There's more.

You are correct that your size is not common, but it does appear on Schwalbe's website, albeit marked a bit differently.

As said, 700 is the diameter, just to confuse matters the same size is also 29er or 28" - some tyres are marked with both.

The 42 width is the width in mm, which converts to 1.65".

Lo and behold, there is a 28" X 1.65" Smart Sam on the website.

But it's not quite the same tyre because it has the thicker carcass.

If you click on the spec link you will see 67 EPI - that's 'ends per inch' which is the same as 'threads per inch'.

https://www.schwalbe.com/en-GB/offroad-reader/smart-sam.html

 

[stuarttunstall]

Thank you... I will check when I go outside but I think the wheels say "29" on them

I was doing some research on tyres and noticed that you had what they call "french" which is the "700xXX" size and then the imperial... very confusing for a novice lol...

I suppose when the time comes for tyres I need better one's and I will be asking for advice when the time comes

I expect it is like everything OEM, they are just cheaper versions, like software etc and when you buy a "retail" version you pay more and in the case of tyre get a little better quality build....

 

[Heltor Chasca]

I really rate Smart Sams. I have 27.5 x 2.35 on a MTB and at the moment 26 x 2.1 on my tourer (in off road mode)