Needed a replacement 700C front wheel for my commuter bike after the old aluminum rim exploded like a looney tunes cannon. It’s hard enough to find the right size when there are 3 competing tire/rim sizing systems currently in use, it doesn’t help when the people selling the wheels have no idea what the numbers mean either! All of these examples are from separate storefronts at the big online store. Ended up buying the wheel identical to mine from my local bicycle shop at the same price as online and with no shipping fee or delivery time.
The 3 systems in use are the American customary inch fraction notation like 26x1+3⁄4 (which is NOT interchangeable with American customary inch decimal notation like 26x1.75), the French metric notation like 650x45C, and the ISO 5775 metric notation like 47-571. I found the wikipedia conversion tables and Sheldon Brown’s tire size chart invaluable.
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700cm
I wanted to go with this, but had to go even bigger. The largest mine truck according to the wiki is BelAZ 75710 (as seen in the picture) which has “59/80R63” tires that are merely 402.7cm big.
You know there’s only one thing to do now, right? You have to make a 7-meter-tire tall bike.
(Don’t blame me; I don’t make the rules.)
The fact that everything from heroin to cocaine was found in everyday products in the Victorian era is the only explanation I can come up with for the penny-farthing bicycle to not have been a one-off idea that everyone dismissed as ridiculous.
I see the problem, it looks like Amazon. Stop shopping there
Boom, problem solved.
Competing standards and clueless sellers are bad, and then the tire marketing makes things even worse.
Marketed for road? That’s 700c.
Marketed for mountain? That’s 29".
Marketed for ebikes? That’s 28".But all three tires fit on the same 622mm diameter rim.
This is a great gotcha! I just recently learned that 700C, the “29er”, and (some) “28 inch” are all the same wheel.
If anyone finds themselves in this position, you should ignore everything else and just look at the ERTO size, which should be on the tyre itself. This is a standard way of measuring tyres and wheels, and is much better than the old ways
I’d love to use ISO sizes, but even if I know that I need a 40-622 wheel, there is no way to search for it on the storefront if every single seller made gross mistakes in labeling their product! I have to ignore the specs shown entirely and make educated guesses based on title alone. For example “WHEEL AL 700 FRONT ALEX AP18 QR Silver UCP” in the picture is almost certainly a 700C wheel and NOT an 18-inch wheel. The “18” in the title probably stands for 18mm rim width, which means that this wheel will fit my bike and tire, but is a bit more narrow than ideal 23mm. The sellers must be copying the title verbatim from the manufacturer, and then haphazardly filling out the specifications without knowing or understanding the actual numbers. The ISO size is not mentioned at all.
90% of listings on aliexpress or amazon are made by dropshippers who don’t actually have any knowledge of the products they’re selling. They scrape the datasets for all of the manufacturers they source from, autopopulate any required fields and blast out a thousand listings. I’d wager the majority aren’t even human reviewed, let alone human written.
Try purchasing wires or electronic components from Amazon. Same shit, only worse.
Not to mention that Amazon search is happy to ignore most of the words in your search. So you end up sorting through pages of results that don’t match. Absolutely infuriating and one of the reasons that Amazon is my last choice now. Someone decided that it was unacceptable to show “no matching results” and lost my business.
Part of the problem is that some seller cram loads of words into the article that have no real connection to the article as such.
For components and wires that are made to a spec, I feel far more comfortable buying from CPC or Mouser.
Amazon sellers just feel like a coin flip if the guy is going to ship you CCA 24 AWG instead of OFC 23, in the hope you don’t notice or bother complaining.
and this is why i basically ignore online shopping except for a few things, it’s utter nonsense and almost certainly completely automated with chatgpt at this point, you might as well donate to the church and pray that god puts your desired item in the mail before sunday.
I’ve had Amazon listings where the title, description, specs on the box, specs on the product, and the reviews ALL had different information.
Who creates these listings? AI?
That said, I strongly encourage anyone who shops on Amazon to complain about issues in your reviews, and contact the seller if ANYTHING is wrong with your product. I have a 99% success rate of getting replacements or a full refund while doing this (resulting in basically a free product), even if the issue is cosmetic or a personal dislike. Just be honest.
What I do is take a capture of the page, then if they haggle on the refund I can clearly show that the product is not the one I ordered.
Absolutely!
And I’ve had companies offer me a discount on product, rather than a full refund or replacement. I always refuse and state how disappointed I am. They pretty much always follow up with a full refund or new product.
Hell, I even ordered an indoor spin bike, complained that it used non-standard crank arms, and they refunded me $100 to replace the crank arms and pedals! Just for stating that I was unhappy with one aspect of an otherwise great purchase.
700C is dang hot, are you building a rocket or something?
To be fair, when I was little I too was guessing that “C” stands for centimeters or something metric. Now I know that “C” in “700C”, the most popular road/hybrid wheel size, stands for the third size in the French “ABCD” notation, where sizes “700A”, “700B”, and “700D” are obsolete and are no longer manufactured.
I’ve experienced this sort of thing with my car. it’s a old 50s car that had a engine swap and a few mods before I got it. so one one hand everything is universal but on the other hand I don’t know what is stock. I only know what sizes are currently under the hood. which wouldn’t be a problem if the guys at AutoZone or O’Reilly’s knew what the different sizes ment. Before I finally figured out what car my engine came from. id just measure the part I need. come in and tell them the part I need, and they would just sit confused until they just asked me what car is this part going into. sometimes the part happens to be stock bel air size, but sometimes they weren’t and the guy would have to bring the used part to the back. until they found something the right size. Hell even when I ordered online id have to wonder if I’m going to be fighting the “guarantee to fit your car thing.” because I don’t know if stock will work. Here at least you can navigate if you managed to find a conversation calculator. My measurement standards don’t matter no matter what unit I use.
