I see no problem in riding on 84" for racing and some training. My observation was that I don't think it is a sensible gear in the long term, especially if you are riding on undulating terrain or in urban areas, especially if you've had knee trouble previously.
As a general observation, there is a tendency amongst cyclists to ride bigger gears than is necessary which isn't helped by the cycling industry tending to fit 53/39 chainrings as standard to their products. That gearing is sensible if you're racing but for the majority of riders lower gears would be beneficial.
I see no problem in riding on 84" for racing and some training. My observation was that I don't think it is a sensible gear in the long term, especially if you are riding on undulating terrain or in urban areas, especially if you've had knee trouble previously.
As a general observation, there is a tendency amongst cyclists to ride bigger gears than is necessary which isn't helped by the cycling industry tending to fit 53/39 chainrings as standard to their products. That gearing is sensible if you're racing but for the majority of riders lower gears would be beneficial.