finished anotherone yesterday...first time with a grubee...the grubee came with 410 chain instead of 415....unfortunately the kit from gas bike had a 415 chain tensioner...it was very tricky to keep the chain from derailing where i usually put the tensioner about 3 to 4 inches from the rear sprocket...instead i had to place it about 12 inches away...when it was at my normal mounting point i would crank the wheel and watch the chain walk from side to side on the tensioner causing the chain to fall off either side of the gear....does anybody know about a thinner tensioner for the thinner chain???cause i would only build with this thinner chain if there is a correctly sized tensioner...i liked the smaller chain when i rode it it is much easier too peddle and will be less drag on the motor(once i get it broke in) your input is always apreciated thanks