Effectively it is;

All NSR gearbox 1st, 2nd and 3rds are the same.
The mc18 is geared lowest (and thus closest) on 4th,5th and 6th.
Then the mc21, then the '28 is geared highest.

But the '28 has a lower final drive (it's only geared for 115mph flat out in 6th) so the '28 as a whole bike has the lowest gears. Add that to what is in the real world a far more flexable motor in stock form than any mc21 or mc18 and you have a bike which gives overall very similar on road performance at legal speeds.
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