Everyone I talk to about their own MTB sizing is so different. I think because there's so many varied ways to "do" mountain biking. Some want all-day endurance fit, some want air-born balance, some want climbing or downhill efficiency.

Some want slightly smaller sizing than the charts, some want slightly larger... and different mountain bike brands have their own take on this too.

If you already know what your doing, I'd say go with what feels right.

Personally I look for frames with low BB heights, short chain stays, a bit longer top tubes so that I can use really short stems which I like the feel of.

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