1 3/8" - 1 3/4" - etc?

[Road Master]

I've got a Hercules 3 speed I want to rat out some and I've been wondering if a 1 3/4" S-7 size tire will fit on the English Bike rim designed for the 1 3/8" tire? And are there any wider tires that would fit on the English rim? Thanks!

[ratina]

I don't think it will fit

[expjawa]

Definately will not fit. The S-7 has a bead diameter of 571 mm, the British roadster tire is (most likely) 590 mm. No matter how much you try (or curse), you won't be able to force the tire that's 3/4" smaller in diameter over the rim of the bigger wheel. It's like trying to put 14" car tires on a 15" wheel. The 590 size is, however, the same as a 650A tire. You might be able to find something that fits that's wider that way, but I wouldn't hold your breath. You're best bet is to actually change wheel diameters in order to use a wider size.

[DaBigKahuna]

Taking this a step further, is there anyplace that has a reference that compares the different sizes both in rim diameter and overall tire diameter etc?

[expjawa]

I'm not aware of one. Sheldon Brown's site breaks down the size matrix pretty well, but I don't think it has anything that ties it to width and overall size.

Overall diameter is a factor of width. Even though, for example, a 26x2.3, 26x2.125, 26x1.95 and 26x1.75 all fit the same 599 mm rim, their widths are obviously different. Their outside diameter is different too, since the tire is more or less a balloon with a round cross section, generally, and it's height on the rim is roughly equal to how wide it is, within reason. Rim width will influence the outcome; a wider rim will make a wider, but shorter cross section, while a narrower on will lead to a narrower contact patch and taller tire. Just like on a car tire/wheel.

I've got a spread sheet that I created that has a row for each major rim diameter, lets you input a tire width, and in turn gives you the approximate overall diameter. It also calculates speed of that tire for a given crank cadence, with that and gear numbers you input. I'm sure someone could clean it up and make it so you can pull down a rim diameter and it'll calculate the rest and display only the pertanent information, but I like having all the sizes layed out so I can see them. Anyway, if you PM me your email, I can send it to you. The offer's open to anyone that might be interested. This sort of thing out to be posted where people can use it.

[deorman]

Useful chart. http://www.isisconsulting.org/catalog/bike/p2010.htm

[hubgearfreak]

I've got a Hercules 3 speed I want to rat out some

i see schwalbe do a 42mm tyre for a 590 rim.

http://www.sjscycles.co.uk/schwalbe-mar ... prod20561/

is there not a shop in the usa that stocks schwalbe?

[expjawa]

Schwalbe is somewhat less common here, but there are some folks that use them frequently. I haven't come across that size yet, I'll have to keep a lookout for it. It should be good for 1/2 to 5/8" more in the tire diameter.

[Bicycle808]

you can buy schwalbes direct at http://www.schwalbetires.com/ You can sometimes find better prices elsewhere online, and they are sometimes "out" of a particular tire in a particular size, but they are all there.

I've been extremely pleased with every schwalbe I've ever run. (Marathon plus, delta cruiser, fat franks, prolly a few others i cannot recall right now)

-rob