About 10 years ago...I bought this 2003 "Yamaha flat black Matte Vmax.
Lemon pledge or S-100 engine brightner was used on the bodywork & motor for many years with no ill effects.
Compared to other 03's that were only washed & left be...my bike seemed preserved from fading, weathering, & also looked better in the long run. I'd wash, blowdry, mist pledge or s100, lightly wipe, & the bike had a detailed look for hundreds of Miles.
Your call on 2013 gray matter tenere, but my 2003 yamaha matter black was fine with lemon pledge sprayed on the motor,paint, frame, fork legs, etc...