Very stupid question.

[Incontinentia Buttocks]

Hello, I'm going to use my mtb every once in a blue moon to cycle to work along the towpath (I normally commute on my road bike everyday but thought this may be fun). It currently has monstrously chunky 26x2.3 tyres and I want to change them to something akin to a road tyre, the only problem is i don't have a clue what size would fit, could some of you good folk enlighten me please?
Many thanks

 

[Yellow Saddle]

26 x 1.5 or perhaps 26 x 1.2 if you can get them. 26 is the wheel size which you can't change, the other dimension is the width, which you can fiddle with within limits.

 

[Incontinentia Buttocks]

Brilliant stuff thank you. Would I be able to shoehorn the existing inner tube in or should I get some new ones?

 

[roadrash]

i can highly reccomend these..
http://www.chainreactioncycles.com/...gclid=COPs-OfJlMUCFSkGwwodK70APw&gclsrc=aw.ds

 

[DCLane]

It's not a stupid question at all;

On my son's MTB (ex-mine) I've Schwalbe Land Cruisers - 26 x 1.75" or 1.9" (can't remember!) on a Felt Q200. Very good on the road and OK off it.

On my retro GT Timberline MTB I've fitted Schwalbe Hurricanes - 26 x 2" - and I'm impressed so far. We used them today on-road and on a gravel / pitted trail and they work well.

 

[CopperCyclist]

Brilliant stuff thank you. Would I be able to shoehorn the existing inner tube in or should I get some new ones?

You would 'probably' be able to use the existing ones. It's easier using larger in smaller, as opposed to stretching them wider than they are meant to go. That said, I put the "probably" in because it's hard to know what size inners you have in already. If they were already at the lower end of their recommendation (which I doubt) then it may be a bit of a squish and risk pinch flats.

In short, I'd do it. If it's going to fail, it'll probably fail quickly!

 

[Incontinentia Buttocks]

You would 'probably' be able to use the existing ones. It's easier using larger in smaller, as opposed to strong them wider than they are meant to go. That said, I put the "probably" in because it's hard to know what size inners you have in already. If they were already at the lower end of their recommendation (which I doubt) then it may be a bit of a squish and risk pinch flats.

In short, I'd do it. If it's going to fail, it'll probably fail quickly!

@CopperCyclist - Is that you Andy? This is Chris.

 

[Pale Rider]

No need to go very narrow for lower rolling resistance.

Wider tyres can roll better - see the first link.

So you could get something like a Schwalbe Big Apple or Big Ben in 2" or just over, which would fit your existing tubes.

http://www.schwalbe.com/gb/rollwiderstand.html

http://www.schwalbe.com/gb/tour.html

 

[Richard A Thackeray]

I used to race MTB on 1.5" tyres, with no issues, so towpaths/bridleways ought not to be a problem

 

[Trembler49]

I used to race MTB on 1.5" tyres, with no issues, so towpaths/bridleways ought not to be a problem

I'm also a big fan of 26 x 1.5, which are better on the road as well. Narrower tubes are easier to fit when you puncture. Otherwise it's like changing a duvet cover.

 

[ufkacbln]

Look at the rim of the wheel (or on the present tyre) for a number that is in the format XX-YYY

XX is the width of the tyre and YYY is the diameter of the wheel

The width can be varied within reason, but the diameter is fixed.

25-559 would be a narrow 1 inch width tyre on a typical mountain bike, and 50-559 a wide 2 inch tyre and would fit the same wheel

It is more accurate that the "26x1.5" format as these are unreliable.

This page from the CTC explains

 

[Incontinentia Buttocks]

Thank you for all the replies, got the 26x1.5 city jets. Rode the towpath and though it was a lot harder work than the road bike it made a great change.

 

[Dave7]

No need to go very narrow for lower rolling resistance.

Wider tyres can roll better - see the first link.

So you could get something like a Schwalbe Big Apple or Big Ben in 2" or just over, which would fit your existing tubes.

http://www.schwalbe.com/gb/rollwiderstand.html

http://www.schwalbe.com/gb/tour.html

That (first) link is facinating............I would never have thought that.

 

[Steady]

I was in a similar position, and I went for these http://www.chainreactioncycles.com/michelin-city-bike-tyre/rp-prod69985 a few years ago, I think I went for 1.4" version (but memory fails me on that), getting rid of the knobbly bits seems more important than width to be honest.

That said, I fitted the above fine with existing standard MTB/cheap inner tubes.

Just be prepared for everyone to tell you that your tyres are knackered, everybody who saw my bike without knobblies told me I should get new tyres.

 

[Butty1972]

http://sheldonbrown.com/tire-sizing.html

This will show you what size tyres will fit what size rims...