"The restrictions being...?"

ok...thought they were pretty obvious based on the post.... but....

'Vertical drops'. Only serve to save 1 second in changing your tire. As a tradeoff, the biek is restricted to a drivechain with a chain-tensioning device.


Also,

2. Light frames - to save a few grams, which really only wins close races, you get tight tolerences, which restricts tire size, loose eyelits, which restrict fack/fender mounting, and lighterweight tubing restricts longevity. Lightweight wheels restrict rider weight, and minimal-spoke wheels (when combined with tight tolerences) restirct riding on a wheel with a broken spoke.

3. Threadless headsets. Restrict dynamic handlebar height.

4. Indexing - restricts componentry by forcing compatiblity.

5. Clipless - restricts ones eagerness to use the bike for errands, etc. Restricts the bike from being borrowed by other riders.

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