Having tried standard screen, standard screen and Touratech spoiler, Puig tall screen and Puig tall screen with Aerotrim spoiler; I concur that adding a spoiler is the more effective solution (for me anyway).

I found that just sticking on a bigger screen, while keeping more wind off you, increases turbulence behind the screen (barn door effect). It's logical really, it deflects more air, but that turbulent air has to displaced somewhere in the form of drag.

I think the fact that a spoiler allows some air to flow behind as well as in front, reduces drag rather than increases it. Adding a spoiler to the top of the (already tall) Puig screen made it perfect in terms of wind protection and clean air, but it impaired forward vision (and got in the way standing).

I've gone back to stock screen and TT spoiler. This I have found to be the best compromise between protection, buffeting and clear vision. Plus, you can quickly remove the spoiler on a hot day to get cooling air (and flies) on your neck and face.

It is worth looking at disturbing the airflow coming up round the forks. My combination of spotlights on GULG brackets and handlebar bag seem to have done enough of a job in this respect.

Best way forward though is to experiment with card, tape, cable ties and old visors (as mentioned). Lash up different permutations of screen height/spoiler angle and see how it goes; then buy whatever setup is closest to your solution (or make something more permanent yourself).

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