[Closed] Rim width

Different but not always better.

Narrower rim means a more rounded profile but a wider rims means you can quite often run lower pressures. You pays you money you takes your chance.

Really? i thought the idea was to get a square-er profile as possible?

Yes I too think he is confused.

Back in the day narrow rims were best cos you got less pinch flats. But you were running 50psi. This had to be balanced against how easily brake pads would cut through your tyres

I'm running Bonty XR4 2.35 on narrow rims Less than 19mm I think. They specify 28mm rims.

If I run lowish pressure the tyre moves side to side on corners, which I don't like. If I pump them up a bit the wallowing stops and they're still nice and dont ping me about because they're huge.

Sheldon Brown reckons all mountain bikers run rims that are too narrow
[url= http://sheldonbrown.com/tire-sizing.html ]See the tyre sizing bit - click[/url]

Sheldon B is the one you listen to - as opposed to any other Sheldons you may come across 😉

Yea - way to narrow according to Sheldon!

Well anyone tried a 2.1/2.2 tyre on a wide wide rim?

i use maxxis crossmarks on mavic ex823 rims for strength, i'm a big heavy fella an i don't want to keep breaking stuff so i go for strength above weight.

Depends what you want - I quite like the rounded profile that you get from running tyres on narrower rims, I also find the tyre protects the rim more from rock strikes etc cos it's a lot wider than the rim.

I was testing the American Classic wheels reviewed in the current issue of ST and while they're great rims, nice and light, very stiff etc, they're also VERY wide - 27mm which is up there alongside some DH rims (eg Mavic DeeMax are 28mm). As a result they simply wouldn't cope with anything less than 2.2" tyres and even those had a very square edged profile, there was a definite 'transition' point as you leant the bike into a corner whereas with my usual narrower rims the tyre was much more predictable when leant over.
2.3" tyres worked better.

Yes I too think he is confused.

What it unture about what I've said?

You can run lower pressures on wider rims and you do get a rounder profile on narrower rim. Both have there advantages.

TheBrick said:
What it unture about what I've said?

Is cynic-al referring to me or you? I'm confused.

Wider rims always felt more stable to me, probably because they do give a squarer profile for a given tyre size.

In general, wide rims work better with narrow tyres than vice versa.

Don't trials riders use big wide rims so they can run super low pressures without pinch flatting and also so they can use big wide stable tyres?

I was referring to thebrick.

In one sense you can run lower pressures on wider rims but you are more vulnerable to pinch flats on wider rims, all other things being equal.

729 rims here with 2.35 Verticals. Solid performance.

32 -38 psi's

729 rims here with 2.35 Verticals. Solid performance

From looking at the mavic site, 29mm internal / 36mm external. Verticals are known to come up slightly small.

I'm convinced. Thanks all

In one sense you can run lower pressures on wider rims but you are more vulnerable to pinch flats on wider rims, all other things being equal.

Why? I've not thought through the mechanics of it yet, but on the face of it I'd say neither were more or less likely to pinchflat - pinches occur when the object pins the tube (in the tyre) between the rim and he object. I don't see either preventing/reducing that (pressures kept the same). Why do you think wider=more flats?

*whoosh*

narrower rim = more of tyre to compress before ground hits rim.

simples.

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