Hard Luggage Stability Issues

[Biker Mike]

From experience, the bike will typically give steering wobble on deceleration below 40mph if the top box is fitted and loaded.
It can also go into a more significant tank slapper at speeds above 100mph if you're heavily loaded (say, over 50kg in panniers and top box).
This may be less noticeable if you're riding two-up, but I can only speculate as I only ride solo.
Leaning forward over the tank will bring the bike back under control.

[alan sh]

It will also do that if the rear suspension rebound damping is too light.

[Rev Ken]

FULLY loaded, top box and panniers, plus tank bag; 120mph German Autobahn, cross wind,  entirely stable! (PR4s).

[twotractors]

had my mk 1 fully loaded on trip to scotland,going up the brilliant last few miles to jog couldn't help but "give it some"no problems at all and thats a very open bit of road with a side wind usually

[Ardi]

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