It can't hurt and was recommended by Mama Yama for the Gen1 bikes. I use the little bottles that Yamaha sells, as Dufus Me can figure out the ratio if it is one bottle to one tank.
Be careful, I used the stuff costco sells, the Chevron stuff in a 2008 Jeep, and it caused 4 injectors out of the 6 to fail whithin about 1000 miles. I'm happy to not use now, and no problems. Sometimes better leaving things alone.
I use a very mild dose of Silkolene Pro-Boost with every tank fill-up. I've been doing this for years on every bike. It helps keeping the system clean.
I routinely use a mild additive. Lucas or MMO, mainly for the upper lubrication qualities, then mild detergents.
Tend to stay away from the harsh ones.
I had an '07 FJR that had an off idle stumble for years and attributed it to the lean tuning. Later I had another throttle issue and threw tons of additives at bike including a high concentration "shock treatment". As part of that troubleshooting effort I sent the injectors to be ultrasonic cleaned and they showed mild blockage (at only 25k miles). Turns out the throttle issues were due to ECU/battery problem but my take-away was the fuel additives don't do much for injector cleaning. Save your $$$ and have the injectors professionally cleaned.
I use Gumout Multi-system tune up or Redline SL-1 for fuel system cleaning and K100MG for light cleaning and winter fuel stabilization. The K100 really does seem to make the engine run better but it is a little too pricey for me run all year around.