Presuming it's a std roadbike make sure;
The frame is straight.
The forks are straight and in decent nick.
If you want a nice road bike, make sure all the bodywork is o.e. Honda.

As mentioned make sure the RC valves work, take it for a test ride, even resticted they run well in the first 3 gears. It's pull OK till around 8000 rpm or so, then may splutter a bit if it's not been used much or pootled through town too much as it comes onto the pipe but should then pull briskly and smoothly round to 11000 or so, If not it could just be setup, or it could be the RC servo.

Std and restricted it'll feel a world away from a std UK RGV, smooth (to say it's got no balance shaft), quiet and TBF a lovely roadbike.
All the girls who buy CBR400's as they're small should buy MC21's as they just as small and 40kg lighter.

Yes they're all restricted, a hole saw and a soldering iron are all you need to sort it out though. Andy can do them the dark.

21r, 1990? hard to call really without seeing it, under £1500 probably and it's the wrong time to year to sell...maybe a grand??
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