I use stuff called Bumper Care made by Autoglym, possibly not available in the US.
I suspect almost anything manufactured by reputable companies for plastic bumpers on cars will be fine.
One just needs to be a bit careful to rub it 'in' thoroughly because it can make surfaces a bit slippery/slick.
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Mike - Riding on the right - riding for pleasure!
'09 Silverwing 600 - 'The Winged Express' - Delta Blue, ABS, Heated Grips, Givi Airflow Screen, Utopia rider's backrest, Givi pillion backrest & E52 Topbox, Cortech Super Mini Tank Bag as a tunnel-bag, Starcom Digital Comms System.
www.x9ownersclub.co.uk - for all Maxi-Riders who want to RIDE!
"All that is necessary for the triumph of evil is that good men do nothing."
Edmund Burke