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Jul 19, 2011
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Central Indiana
Rating - 100%
2   0   0
Since I've decided to jump into a little road biking, I need help understanding some wheel tech.....

1. What's the difference between 650c & 700c wheels?
2. What does each number represent?
3. There's usually a number like 38mm after the 700 or 650; what does that stand for?
4. Are 700c wheels 26" diameter wheels?
5. I think I know what Deep-V wheels are, but can someone clarify it just in case I'm wrong?

Thanks in advance!
Toeslider said:
It gets confusing, but you can start to figure it out by reading this:

In very broad terms, the 700 refers to the overall diameter of the tire in millimeters, the "C" refers to the general width of the tire, the number after it refers to the inner rim width.

Now that my brain has had a few minutes to relax after locking up........thanks! That helped!
I don't claim to understand it all, and I don't think that article completely clears it up, but it gives you an idea of how the numbers came about. It seems like bike tire and wheel sizes are similar to stereo specs, where "100 watts" could be just about anything. The one that gets me is that, to this day, a 1 3/4 tire and a 1.75 tire are NOT interchangeable! Doesn't seem like that should be possible, but it is.
The wierd logic I've used for tire stuff is if it has a fraction size like 3/8 or something, the same type of tire would replace it. The same goes for something with a decimal size like 1.75.....