What is the widest tyre you can add on a 23mm rim and why?

[Ajax Bay]

I had a bicycle with a 700c x 37c wheel with a 23mm wide rim and I always felt the [London] roads were quite rough. At the moment I am using a rental bike with a 700c x 47c wheels and the roads are a lot more comfortable. I was wondering if I end up buying the same bike I had before that comes with 700c x 37c wheels with a 23mm rim, what would be the widest tire I could possibly add to it?

The OP's rim is 23mm wide (outer) so internal width with be max 18mm. Sheldon recommends the maximum multiplyer is 2.0 so 36mm tyre. The 37s the OP has on are already max recommended.
I agree with all the sentiment expressed in the comments above: don't over-inflate the 37s and get your backside used to the comfort of 37s and reduce your expectations, or buy a bike (probably 26" wheeled) with wider rims. and run 1.95" tyres (slicks).

 

[Alex321]

Well, I always pump it to the maximum so it rolls well

You shoudn't. It will certainly be less comfortable, and unless you are on extremely smooth tarmac, will also be slower than having it softer. If the tyre is pumped up too hard, then it can't absorb the bumps, it bounces instead, which is less efficient.

nooooooo. 37c is still pretty slim. As I said on the rental one is 47c and it feels a lot better

37c is exceptionally wide for a road bike. 47c will only normally be found on mountain bikes.

Most road bikes will have tyres between 25c and 30c. Not many can take even as much as 35c (frame clearance).

 

[MontyVeda]

I've got Big Apples (just measured at 55mm*) on my Snyper 23mm rims. Been on for years. No issues. (PS. it's an MTB)

*which means i've got the skinny 2.15 version and not the 2.35 as I'd always assumed

another edit...

...what would be the widest tire I could possibly add to it?

Surely that's defined by the frame... the width between the forks/seatstays??

 

[Sittingduck]

37c is exceptionally wide for a road bike. 47c will only normally be found on mountain bikes.

Most road bikes will have tyres between 25c and 30c. Not many can take even as much as 35c (frame clearance).

I think the world has moved on these days. I am comfortable running anything from 28-38 on various 'road' bikes.

 

[Alex321]

I think the world has moved on these days. I am comfortable running anything from 28-38 on various 'road' bikes.

When I was looking middle of last year, most disc brake models were listed as a maximum of 30 or 32, with a few going to 35.

Almost anything that would take more was listed as a "gravel" bike. My Cube Attain says a max of 30 (without mudguards), and came with 28.

 

[Ming the Merciless]

keep saying that to my boss but he refuses to retire

Maybe he could retube

 

[Ming the Merciless]

When I was looking middle of last year, most disc brake models were listed as a maximum of 30 or 32, with a few going to 35.

Almost anything that would take more was listed as a "gravel" bike. My Cube Attain says a max of 30 (without mudguards), and came with 28.

28s is so last decade with road bikes

 

[Dogtrousers]

As always, Sheldon has the answer:
https://sheldonbrown.com/tire-sizing.html#width

 

[Alex321]

28s is so last decade with road bikes

There are an awful lot of last decade bikes around being sold as 2021/2022 models then

I just had a look to see if it has changed much in the last 8 moths since I bought mine. Looking at mid-range road bikes (around £1500-£2500), there are more sold with 28mm than any other size. A few 25 or 26, a few 30 or 32, but more 28 than all of the others put together. That was looking at several websites, and bikes from about a dozen manufacturers, 2-3 models from each.

 

[Ming the Merciless]

There are an awful lot of last decade bikes around being sold as 2021/2022 models then

I just had a look to see if it has changed much in the last 8 moths since I bought mine. Looking at mid-range road bikes (around £1500-£2500), there are more sold with 28mm than any other size. A few 25 or 26, a few 30 or 32, but more 28 than all of the others put together. That was looking at several websites, and bikes from about a dozen manufacturers, 2-3 models from each.

Well if people want to be suckered into what was being sold in 2010…

 

[Ming the Merciless]

In the 1980s my road bike, or racing bike as they were called then, came with 32mm tyres. It really is back to the future with road tyre widths.

 

[MontyVeda]

As always, Sheldon has the answer:
https://sheldonbrown.com/tire-sizing.html#width

"This chart may err a bit on the side of caution. Many cyclists use slightly wider tires with no problem."

I've been using significantly wider with no problem; 55mm on a 17.5mm internal

 

[Dogtrousers]

"This chart may err a bit on the side of caution. Many cyclists use slightly wider tires with no problem."

I've been using significantly wider with no problem; 55mm on a 17.5mm internal

Yeah I've used some pretty odd combos too, and did not die. Not as extreme as yours though.

 

[CanucksTraveller]

I had 20mm tyres on my bike in the early 90s, they were 110psi bone shakers!
I'm on 35s now, actually the same model tyres come in a 40 as well so if the frame clearances worked out you could even go bigger. Super skinny is a last century look.

 

[MontyVeda]

Yeah I've used some pretty odd combos too, and did not die. Not as extreme as yours though.

It never even crossed my mind that it was an extreme combo.
I ordered a new set of tyres yesterday... 2.35" (60mm) so even more extreme!