Who makes aluminum ISO 540 rims? I've been googling like crazy for "wheelchair rims" (which are 540) and getting premade wheels only.

Any leads to rim manufacturers that make 540's would be greatly appriciated!

There are some OEM suppliers in China, but that probably won't help you.

The best place to start might be on a wheelchair racing forum, or by looking at some wheelchairs and seeing if you can find a rim with a decal on it.
It's also possible that a few aluminum makers offer them, but don't list with the bicycle products. Try your luck with Sun Metal, and maybe one of their people can give you a lead.

Over the years, I've found all sorts of good connections, by calling companies in relate areas, getting someone in sales or purchasing, and working leads from one to another until I found someone who could help. BTW- in most industries are small worlds, where everybody knows each other to some degree so once you have one name, it'll open doors to others, as in "I was speaking to XXX and he said you might be able to help".

Sun CR-18 rims are available in 540mm ERD:

https://store.qbike.com/rim-sun-24x1-...ck-36-540.html

+1 on the Sun CR-18s from QBike.

I just built a set. They only come in 36 hole. Ben's Cycles also has a set of 28h Fiamme rims for cheap! But 28h lightweight rims. . . Depends on the end use.

What ya gonna put these on?

You may get more search results by trying the nominal size, 24 x 1 3/8

Tried that and got no forwarder.

..what are these going on? is there easy tire availability?



both hard to find suggests it's change time

As noted above, Sun offers the CR18 with a 540 BSD (aka 24 x 1 3/8). Be careful about sourcing, because they also offer it with a 507 BSD (aka 24 x 1.50).
https://sun-ringle.com/wp-content/upl...chart_2012.pdf

Amazon has some ISO540 tires.

Old kid's road bikes. Don't have a good alternative for sizing. I could call Sun (again). Last time they said they didn't have any.

have you given your LBS a shot at it?

Flow path is Manufacturer> distribjutor> retailer ,
and it usually works better to have the retailer ask their distributor.

the one out here has several they have accounts with..


dug out my Sutherlands their listing has a French 600A, at 541..

and the 540 in a British and Italian column .. [pg 12-25 3rd edition]

They're having problems too. Either would work (600A or 540's)

The next issue is who makes tires and tubes in 540 mm, are they good for your purpose, and will they be at the LBS that you limp to on the next ride. In my experience, at least, there are only a few choices and they are only available mail/online.

The one bike I restored that had 540 mm rims (actually French 600A which is 541 mm), I replaced with narrow 559 mm (26"/MTB) rims for which there is a good selection of tires and tubes, and a decent chance of finding one at a LBS. Also easier to find said rims used, and in the correct drilling (# spokes) for your hubs.

Check your brake caliper reach and frame clearance, to see if this is an easy swap.

A friend with 2 sons, bought 2 of these ..https://www.feltbicycles.com/Internat...-Bike/f24.aspx

For kids bikes, Kenda makes a reasonable road tire. Many wheel chair racers run 540 size wheels & tires.

The link for the Qbikes source should still have stock of these rims. As noted above, I bought a set to build only a couple weeks ago.

So much revolves around the frame you have to work with. It is really nice to have wheels that are the right size.

I built mine on fine Campy Record hubs, too.