Kymco Agility 125 Confusion

[Vision]

Hi guys, great board you have here. I need some help. I purchased a new 2010 Agility 125 last summer. It has 2,700km on in.

1. Yesterday I performed my first oil/gear oil change (not the first service for the bike). I used shell rotella t 15/40 synthetic in the engine and this from royal purple in the gear box.

Royal Purple 01300 Max Gear 75W-90 High Performance Synthetic Automotive Gear Oil.

It has friction modifiers in it, did I make a mistake?

http://www.amazon.com/dp/B0007QGT34/..._M3T1_ST1_dp_3

Max-Gear is an ultra-tough automotive gear oil. It's designed to maximize power and provide unsurpassed protection to heavily loaded gears. It makes gears run smoother, quieter, cooler and longer without overhauls. Max-Gear outperforms other gear oils because it combines the highest quality synthetic oils with Royal Purple's proprietary Synerlec additive technology. Max-Gear is recommended for use in truck, motor home/RV and automotive front or rear differentials, manual transmissions, and lower gear units of marine engines that specify use of an API GL-5 or GL-4 fluid. All viscosities of Max-Gear are formulated with hypoid friction modifiers necessary for use in clutch or cone type differentials. No additional additives are necessary.

2. In the last 500km I've been getting some vibration as I start off. Yesterday I was stopped, I lightly throttled and the bike paused for a second before lightly lurching forward.

Any ideas?