Wheel sizing

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531colin
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Location: North Yorkshire

Re: Wheel sizing

Post by 531colin »

Pebble wrote: 12 Apr 2021, 11:44am
531colin wrote: 11 Apr 2021, 3:13pm 700 x 30 or 700 x 47 TYRES won't fit under a dual pivot sidepull brake....... the (E bay?) vendor doesn't want to keep getting wheels back from people who have bought the wrong wheel, and the easiest way he can think of doing this is to say they are not suitable for drop bar bikes.....because a lot of drop bar bikes have dual pivot sidepull brakes. (The vendor isn't necessarily an expert in bike mechanics, or a native English speaker, or selling exclusively to native English speakers or expert bike mechanics)
I don't see anywhere in the advert saying what the rim width is? The 28inch in the advert is the diameter.
.(622 -18 would be bead seat diameter and internal width, but I can't see it in the advert ?)
So the seller is of the opinion that the rim width is suitable for 30 or 47mm wide tyres....NOT 25 or 28mm wide tyres which will fit under dual pivot brakes.
there was many different adverts from many different sources, you're wildly jumping to conclusions by assuming I was only refering to one. - which also casts doubt on the rest of your post, just wild speculation.
Perhaps it might help if you wrote something which made sense in the first place.
Be that as it may, I shall try to remember to avoid wasting your precious time in future. Please ignore anything I do write.
Pebble
Posts: 1934
Joined: 7 Jun 2020, 11:59pm

Re: Wheel sizing

Post by Pebble »

531colin wrote: 12 Apr 2021, 1:29pm
Pebble wrote: 12 Apr 2021, 11:44am
531colin wrote: 11 Apr 2021, 3:13pm 700 x 30 or 700 x 47 TYRES won't fit under a dual pivot sidepull brake....... the (E bay?) vendor doesn't want to keep getting wheels back from people who have bought the wrong wheel, and the easiest way he can think of doing this is to say they are not suitable for drop bar bikes.....because a lot of drop bar bikes have dual pivot sidepull brakes. (The vendor isn't necessarily an expert in bike mechanics, or a native English speaker, or selling exclusively to native English speakers or expert bike mechanics)
I don't see anywhere in the advert saying what the rim width is? The 28inch in the advert is the diameter.
.(622 -18 would be bead seat diameter and internal width, but I can't see it in the advert ?)
So the seller is of the opinion that the rim width is suitable for 30 or 47mm wide tyres....NOT 25 or 28mm wide tyres which will fit under dual pivot brakes.
there was many different adverts from many different sources, you're wildly jumping to conclusions by assuming I was only refering to one. - which also casts doubt on the rest of your post, just wild speculation.
Perhaps it might help if you wrote something which made sense in the first place.
Be that as it may, I shall try to remember to avoid wasting your precious time in future. Please ignore anything I do write.
I'm curious, which bit has not made sense to you? I did get some sensible answers to my OP that helped clarify the various measurements around tyres and rims. So my post must have made sense to some.

I am still curious as to why you were suggesting I try and ride the bike without the tyre fitted?
Vorpal
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Re: Wheel sizing

Post by Vorpal »

531colin & Pebble, please try to explain things calmly and *nicely*. Things like 'wildly jumping to conclusions' and ' it might help if you wrote something which made sense' don't advance the discussion, and only irritate each other.

If I may, Pebble: 531colin was obviously referring to the picture with text in that you posted in your OP to being the discussion. I think that referring to that picture was not wildly jumping to conclusions.

The link to Sheldon Brown's tie sizing systems page that jdsk included has a nice little table at the bottom of the page (scroll down) that shows what tyres fit in what rims. It is on the conservative side, but a pretty good guide, especially if you are buying a new wheel.

700c 28 will mean 28 mm width, not 28 inches, so those are approximate circumference and width of the fitted tyre.

531colin has given a good explanation, but I will add that another reason that adverts like that will say 'not suitable for road bikes' is that there is limited fork crown clearance. Most road bikes will only take a 25 or 28 mm tyre, independent of the type of rim brakes because of that. Either way, you need a rim that is suitable for 28 mm or less. If you find 622 - 13 to be too narrow, then it's fine to select something bigger, but 622-19 is absolutely the biggest you can expect to put on a road bike, and it would be too big for some road bikes.

Also, you have to keep in mind that not all 28 mm tyres are the same. Most manufacturers run on the low end of ETRTO tolerance, not just because it save them a little money in materials, but also because tyres tend to increase in size over time and under pressure. it's generally only a mm or 2, but often brings them closer to nominal. That said, it is conceivable that allowable variations in rims & tyres would allow one combination of 622-19 rim and 700c X 28 tyre to fit a road bike, and another combination that have the same theoretical sizing to not fit.

622-13 rims definitely take up to a 25 mm wide tyre. That is wide enough for most uses. 28 mm wide tyres should be okay on most 622-13 rims, even if it is above recommended width (you can check what the manufacturer of yours says?) but in general, I would expect that if you can fit them, they'd be okay. Have you checked your rim for imperfections or loose/shifted rim tape that might cause your problem? Or tried 25 mm tyres, instead?
“In some ways, it is easier to be a dissident, for then one is without responsibility.”
― Nelson Mandela, Long Walk to Freedom
Jdsk
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Joined: 5 Mar 2019, 5:42pm

Re: Wheel sizing

Post by Jdsk »

Vorpal wrote: 12 Apr 2021, 3:01pm531colin has given a good explanation, but I will add that another reason that adverts like that will say 'not suitable for road bikes' is that there is limited fork crown clearance. Most road bikes will only take a 25 or 28 mm tyre, independent of the type of rim brakes because of that. Either way, you need a rim that is suitable for 28 mm or less. If you find 622 - 13 to be too narrow, then it's fine to select something bigger, but 622-19 is absolutely the biggest you can expect to put on a road bike, and it would be too big for some road bikes.
Thank you for the explanation.

Jonathan
Steve
Posts: 388
Joined: 2 Apr 2007, 1:42pm

Re: Wheel sizing

Post by Steve »

Pebble wrote: 11 Apr 2021, 11:47am When you get a measurement for a wheel such as 700-28 (622-18c) would the 18 be the likely internal width of the rim ?

nd what do you think the following means, I have seen simillat on a few descriptions
Image
Not suitable for dropped handlebars !
It's very common in Germany, and perhaps other European countries, to refer to 700c wheels as 28" wheels.
This must be what is meant in the advert clip at the top of the thread.
Vorpal
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Re: Wheel sizing

Post by Vorpal »

Steve wrote: 12 Apr 2021, 4:00pm
Pebble wrote: 11 Apr 2021, 11:47am When you get a measurement for a wheel such as 700-28 (622-18c) would the 18 be the likely internal width of the rim ?

nd what do you think the following means, I have seen simillat on a few descriptions
Image
Not suitable for dropped handlebars !
It's very common in Germany, and perhaps other European countries, to refer to 700c wheels as 28" wheels.
This must be what is meant in the advert clip at the top of the thread.
I did not connect that that's what they were talking about with the 700c 28. Good thing someone did! :)
“In some ways, it is easier to be a dissident, for then one is without responsibility.”
― Nelson Mandela, Long Walk to Freedom
cycle tramp
Posts: 3532
Joined: 5 Aug 2009, 7:22pm

Re: Wheel sizing

Post by cycle tramp »

..anecdotally, I changed my tyres from 26 x 1.75, to 26 x 2 Whilst i had considered the tyre width, I hadn't considered the increase in tyre (wall) height. The slightly wider tyre had effectively changed my 26 inch wheels to 27.5 inch wheels, simply because of the increase in tyre height.
...whilst I didn't have to change the mudguards I had I did have to remount them, just to keep the tyre clearance the same.
Having seen how little tyre clearance there is on a modern carbon fork I can understand why the vendor has typed 'unsuitable for dropped bar cycles'.. however given the fact that many flat barred bikes now share similar forks I think if I was the vendor I would have gone with simply staying the clearance required.
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Jdsk
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Joined: 5 Mar 2019, 5:42pm

Re: Wheel sizing

Post by Jdsk »

cycle tramp wrote: 12 Apr 2021, 9:06pm...whilst I didn't have to change the mudguards I had I did have to recount them...
I think that I know what you mean!

: - )

Jonathan
mattsccm
Posts: 5101
Joined: 28 Nov 2009, 9:44pm

Re: Wheel sizing

Post by mattsccm »

I have to recount my wheels fairly often. :lol: :lol: :lol:
Too many, not enough matching pairs and always swapping them onto too many bikes.
Thought a touch of thread drift might lighten the mood :D
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