So I’m cruising down the highway and here’s yet another teeny-tiny car with a great big bike on a rack. I looked at it for a minute, then realized it was weird. Ordinary enough looking bike, but the wheels had 1" deep rims (chrome or stainless) and just a quarter inch of tread or so showing. I’ve never seen anything like it.
Somebody 'splain?
Deep rims might be for weight or aerodynamics purposes, perhaps a combination of both. Dozens of thin wire spokes whipping through the air has a kind of egg beater effect on the air and creates significant drag. A common method for tackling this problem is to use fewer spokes (or give the spokes a teardrop cross section) but another method is to make the rims deeper hence the spokes are shorter. In the extreme, they also make solid wheels, with no spokes at all.
Did the bike you saw have triathlon-style handlebars on it? Aero rims are popular on triathlon bikes.
Time trial or Triathlon bike probably.
It did not look unusual in any way - generic road/mountain bike, full frame, etc. except for the odd rims. I’ve seen aero rims like those in TD’s examples - sometimes almost full-wheel shrouds - but these were different. They seemed to be completely ordinary spoked wheels, normal inside diameter, but instead of a quarter to half inch of rim and inch or two of tire, it was the other way around.
I thought from a distance that the tires had whitewalls - I remember those from old-fart bikes when I was a kid - but nope, shiny metal.
Could have been a fixed wheel with deep rims.
I had a buddy who put some kind of 26" road rims on his mountain bike (he could afford rims and tires, but not a whole new bike) and did the RAGBRAI in Iowa about 15 years ago.
His bike looked a lot like you describe- the tires looked weirdly thin in relation to the rims and the bike.
It’s for a few reasons - and probably there is more to it than what I write here. Deep dish rims can accomplish a few different things. Due to the shape, They can be more aerodynamic. Due to the lower spoke length they can be stronger and much stiffer. The kind of stiffness they offer can work well on a track where the surface is very flat. They can be very light also - unbelievably light due to the advances in carbon fiber. Sometimes the spokes are also made of carbon fiber also.
650c. Roughly the same diameter as 26" but not interchangeable.
Often used on bikes for women as 700c wheels will hit the downtube on small-framed bikes.
Just do a google image search for weird bicycle wheels and you’ll see many.
http://inventorspot.com/files/images/chinese-bicycle.preview.png (From this article.)
And these.
The peak of bicycle engineering was the Schwinn Apple Krate. It’s all been downhill since then.
Bolding mine. No modern bike wheel worthy of being called a wheel is made from chrome or stainless. Steel is far too heavy and chrome rims brake very poorly in the wet. Any decent rim today will be aluminum or carbon.
