Xceleroin... Am i just being stupid?

[Losi_110]

hi, after having a few problems with my new speedo i thought it was ok, but after trying it out again the motor gets really hot and kinda stalls rather than spinning, i thought i'd stripped a spur to start off with. I didn't know if it could be the gearing, although i ran my lrp with a 6.5 on the same gearing and it's the gearing a guy at the club user on his 5.5 lrp. Have i geared it too low or do the losi motors need hearing lower? Just trying to rule everything out before i send it back to have it checked out. I even got another losi 6.5 yesterday but i haven't had a chance to try it out yet.