First of all I would like to say I am a firm believer in synthetic lubricants. Have used them for years in both cars and motorcycles. The bike I have now is FI 1500cc Kawasaki V-twin and after the first 500 miles has seen nothing but synthetic both in the motor and rear end. I have used Amsoil 20W-50, Shell Rotella 5W-40, Mobil 1 15W-50 (redcap) and Mobil 1 T&SUV 5W-40. The Amsoil 20W-50 and Mobil 1 15W-50 gave me smooth shifts for the 3000 mile OCI's. The Rotella didn't shift as well as the 20-50 or 15-50 oils but other then that it was fine. When Mobil quit making the 15W-50 red cap I switched to the Mobil 1 T&SUV 5W-40, after about 1500 miles my transmission started shifting cluncky and it got worse so at 2500 miles I dumped the T&SUV, after reading some good things about Delo 400 I decided to try it even if it's not synthetic, I was only concerned about the moly in the Delo and my clutch. It was 103 degrees today and I rode about 75 miles and never noticed any clutch slippage, my bike has 34,000 miles on it so if the moly is going to make the clutch slip I would think it will not take to long.