> A number of years ago I met riders on the local bike ride. One participant on the trail ride was well above 6 and a half feet. He had a Gunnar road bike. It looked odd. Odd because the head tube was nearly the length of a top tube for small bikes. It did not look like a Gunnar bike. Another friend owns a Gunner bike. He is 5 feet 10. The tall guy's bike was a bike of course. But it just did not look right. The proportions were wrong.
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> On another ride, we met another rider about 20 miles from home. On the trail. He was 6 feet 8 or maybe 6 feet 10. But his bike looked normal. Normal for his size anyway. It was a mountain or hybrid style bike. With 36 inch wheels. Everything about his bike was sized to the 36 inch wheels it used. So everything was the right proportion. He talked to us about getting 36 inch wheels and a bike to fit that size wheels. Given his height, it made sense to start with a much bigger wheel and scale everything to fit that starting point. Rather than to start with little regular sized wheels, 700C. And scale up the bike frame to meet his larger size. So his bike looked like a normal bike. If you saw his bike, you would think normal bike. It was just 150% bigger on everything. But overall, it was a normal looking bike.
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+1
I was puzzled by '29-inch' until we built up a custom XL
Gunnar mountain bike with them for a very tall rider. It
clicked - proportional is exactly the word.
36 inch wheels may bring their own troubles sourcing
replacements at inopportune times, but the principle is right.
I still don't get XS 29-inch bikes for 5'2" women but we do
see those in service here.