Tire/Wheel Width and Relationship (article)
 

A good read I came across when doing a little digging about the relationship between tire size and wheel width. A chart towards the end provides a guide for matching tire size and rim width.

THE RIGHT TYRE WIDTH ON THE RIGHT RIM WIDTH - Engineerstalk : Engineerstalk

Good topic...I have video about this but still i couldnt record the english one :) Basically multiplying rim width with 1.4 gives narrow limit, 1.8 optimized limit, in older rims 2.2 but for now 3 gives the wider limit of tyre that can suitable for the rim

Good rules of thumb. Do those rules apply to all hooked bead rims?

I was digging around because my new ride came with rims that measure 18mm inside, and I was wondering if I could mount 700 x 28 tires on them. Fortunately, they're a good match. I'll ride the stock Turbo Pros for a while, and then make the change.

Over analysis for 99.9% of people who ride bikes.

+1 Sheldon does it much more simply (scroll down to Width Considerations)

Possibly.

I ran across this years ago when I bought a Trek MultiTrack for touring, only to discover someone had fitted it with skinny Matrix rims that wouldn't even accommodate 700x32 tires. Even with Sheldon's looser guidelines. Same thing happened this summer when a friend scored a very nice Specialized Expedition that had been upgraded(!?) with Mavic open-pros. Even 700x28s were just outside the recommended range. Poor choice of rim for a very capable touring machine.

But as I was learning about this I asked at some shops and they were universally clueless on the topic, which tells me that people get away all kinds of mismatches without problems.

But back to the OP, this article certainly jives with Mavic's decision to widen the new Ksyrium rims. I'm going to save it for future reference.

I have trouble fathoming a rim that would be too narrow to accommodate a 32mm tire given my long experience with using narrow rims and very wide tires. I regularly use 17mm internal diameter rims with 55mm (2.12") tires on mountain bikes without issues. People look at the charts that are around and think they are gospel when they are only poor guidelines that seem to be based on nothing other than what someone thinks should be a limit. Even Sheldon Brown acknowledged that the recommendations in the chart he posted were conservative.

What do you think will happen if you exceed those recommendations in his chart? In my experience, nothing will happen. The bike won't stop working. The tires won't blow off the rim. The tires won't be prone to pinch flats which are due to inflation and impact and have nothing to do with tire width.

When I consider a rim, the only thing I consider is weight and that is only with an eye to how light weight I can get the rim. There's no need to use an overly heavy rim or an overly wide one. Heavy wheels negate any rolling resistance advantage you might gain by using a tire with a flatter profile.

I didn't see anyone has got anyproblem with this method since 1990 :) I told it here in my channel but in Turkish :( In my new channel i will take a new video in English...

I'd just like to know who makes this stuff up...

"Example of reading: a 23mm tyre can be safely mounted on traditional rims of 13mm to 16mm (internal width). On any rim wider than 16mm, it is not possible to use a 23mm tyre safely.

On the other hand, a rim that is 21mm wide internally, can only accept tyres from 35mm and above."

I've been running 28mm wide tires on 23mm internal width rims for like 2 years. And I've read on this very forum of guys running 700x23 on 21 and 23 wide wheels. And look at that, none of us are dead.

When some one speaks in absolutes many assume they know what they speak of, as in they're an expert. We see this frequently in other arenas (like national politics).


Whenever I read a post here and see words like "always", "never", I question the experience or the goals of the poster. Truly experienced and open minded people usually know that they can be wrong at least once. Andy.

+ 100000

I have used up to 2.35" (59mm) wide tires on 17mm internal width rims for an approximate tire/rim width ratio of 3.5, way outside of any recommended ratio. If running low pressure you can feel a bit of squirm, but otherwise totally fine. My road bike currently has 14mm internal width front rim (I had a wider rim but the axle broke in the front hub so I swapped in a narrow one I had on hand) with 33mm tires, and it has no problems whatsoever. There is a tiny bit more aerodynamic resistance with an obvious 'omega' shaped tire casing compared to a tire mounted on a rim of similar width, but I don't think I can actually feel a difference.
Before my current tires I had 19mm wide rims with 38mm tires, and that was also no problem. The idea that you can't run a 28mm tire on a standard road rim is laughable, and not based in any real-world results from running such a setup.

These are not absolute, this method is an advise or to give an idea especially for beginners...If u could understand my language you would here that on the video... By the way i am really surprised that some guys on this forum that used 700x23 on 23 internal width wheels... It seems like to wear a bikini to a bear :D why do they need to use it? :D Why a cyclist wants narrow tyres? Of couse for speed for more performance to take from bicycle... 23 internal width rims are so heavy for it...

well, like I said, people get away with all kinds of mismatches without problems. That in itself is not proof it is safe. It is anecdotal and has some value, especially with you very experienced riders, but I'm not ready to completely disregard guidelines by people in the tire and/or wheel industry with a lot more knowledge than me: Mavic, biketiresdirect (who has a good compatibility chart), Sheldon, etc.

and btw, my mtn bike was shipped with very skinny rims and fat tires, and I haven't had a problem either. But that's a low (tire) pressure situation, and at relatively low speeds. I don't want to be thinking about my road tires on a 40+ mph descent.


Now, can somebody give me some tire pressure guidelines for old French steel/chrome wheels. I've got some alloy wheels on an old Peugeot that seem to be beyond adjustments (the back hub and the front rim are shot) so I went to swap in the original steel wheels and noticed the rims are not hooked. I just acquired a new set of Kenda 27" (cheap) tires on another bike that I can use. What's the max pressure for this situation? Seems like the tires would blow right off the rims with too much pressure (and someone mentioned as much on this forum).

It's a guide, written by some folks who know more about the subject than you or I. Why not read it and learn something?

The who was Trek, factory original.

Personally, I like wider rims because I find them easier to mount and dismount tires with thick thorn resistant tubes.

The seller told me the bike shop built up the frame this way. I think this frame was more commonly setup as a hybrid, but don't really know the history of those Multi-tracks, so that guess is based on what few I've seen.

more on tire/wheel width:

http://https://intheknowcycling.com/...s-wheel-sizes/

Mavic did not offer wide rims at the time the original iteration of that article was written.

Mavic has been understandably biased toward their own relatively narrow rims.



-Tim-

I did not say that the guide was useless or that it contained bad data or that people should not read it and learn from it. I said it was too much analysis for most riders, that's all.

I have read the article, about a dozen times, give or take. This is at least the third thread about that article. It has been discussed at great lengths here on the forums.


-Tim-

Now see, that puts me at ease, because I'm comfortable with manufacturer bias. It's a constant in the universe.

It's not that "people get away with [it]". It's not that much of a problem. It's certainly not as much of a problem as you are making it out to be. Yes, it's somewhat anecdotal but once you've collected enough anecdotes, it becomes data. After 30 years of riding just about every tire/rim combination possible without issue, you can start to see a pattern. That pattern is that it doesn't really matter that much.

Once seated properly, the tire probably isn't going to spontaneously blow off the rim...even at speed well over 40 mph. It's not something that I even think about and it's relatively easy for me to hit 40 mph within 100 to 200 yards from the door of my work.

I have had some blow-off problems with a specific brand of tire but those blow-offs happened on several different wheels over several different years. I no longer use that brand of tire for any riding. Not because I'm afraid of blow-offs at high speed...all of the blow-offs happened at low speed or when the bike was sitting still...but because I don't need the hassle of fixing blow-offs.

Just don't. Life is way too short to ride steel wheels. But, if you must, you should be able to use a reasonable pressure...80 to 100 psi...even on nonhooked rims. No, they probably won't do 130 psi but that's too high a pressure for just about any bicycle wheel.

Some of us have read it (or something like it). The recommendations are way too conservative and are based more on Mavic doing CYA than on anything that I would call "hard" science.

There's a quote I love (which I don't take too seriously), "the plural of anecdote is not data". I tend to apply it to alternative medicine/supplement claims, not bicycles ... whatever. I've got 40+ years of riding all kinds of bikes, but only about 10 or so of serious wrenching/restoring, and I have a very heuristic/seat-of-the-pants approach to that, so articles like the OP's, and the one I posted much later leave me bleary-eyed very quickly. I do learn a lot from hanging out here and asking questions. In fact, I'm sure I asked this forum about tire/wheel widths when I had that Trek some years ago - and I do take people's advice and experience seriously.

https://sites.google.com/site/skepti...te-is-not-data


I would normally avoid steel as well, but this is the original wheelset for a '75 Peugeot mixte I'm selling, and I know the buyer is absolutely a fair weather, slow rider. You know, farmer's market runs and the like. These wheels roll just fine (and will never see rain!). I was surprised when I repacked them. To upgrade, I'd have to find/buy something else and would never get my money out. And btw, I put big ol' Koolstops on the Mafacs.

This is interesting...I am about to build a set of road wheels using Velocity A23 rims, and plan on using 23mm tires. I had read that the narrow tire/wider rim combo yielded a more tubular-like ride.
Now, I gotta wonder........

I wonder if the writers of these kinds of claims ever rode on sew ups much. With a more vertical side wall the vertical compliancy gets harsher. One of the shining aspects of sew ups is the smoother ride as the more supple casing is better able to absorb road shock.


I suspect that the reason some try to compare wide rimed clinchers to sew ups is that when pro racers use a product the rest of us want to also. But the threshold of effort to deal with sew ups is higher then most are able to handle. So we make our little mind games instead to convince ourselves of what we want but won't really get. Andy.

While I agree that anecdotes can be biased and incorrect, don't make the mistake of thinking that they can't be data which is the problem I have with that quote and it's overuse. I'm not even sure that "anecdote" is the correct term in the context of this discussion. I'm not talking about a single incidence nor about a few incidences. More years of observations and "testing" by actually mounting very wide tires on narrow rims than (some) recommendations would suggest. It's never been an issue nor, frankly, something I even think about.

My current touring bike has Velocity Deep V rims on which are mounted 37mm tires. The Deep V, if you aren't familiar with them, are 19mm outside width and a 14mm internal width. Based on the Mavic article and the Sheldon Brown chart, the widest I should use is a 28mm tire at the very most. But the tires have several hundred miles on those rims. The previous rims I wore out had a 18mm width which is at the edge of being suitable for a 37mm tire, however, I never had a problem with them in 10,000 miles of loaded touring.

I also have a cruiser with Velocity Aeroheads on it. The Aeroheads have a 14mm width and I use 2.12" (55mm) tires on them. They are pressurized much higher than my mountain bike tires...60 to 80 psi...but, again, it's not something that I'm concerned about.

My bonafides, by the way, are 40 years of bicycling and 30+ years of bicycle mechanicing. I teach people how to build wheels as well as teaching people to work on their bikes Saturdays at my local co-op.