i just recieved my very first e-bike yesterday, a cyclotricity stealth 500w its great but i cant work out how to use it on power alone,there dosnt seem to be a switch or button anywhere?,it didnt come with the thumb throttle that apparently is extra but the guy at e-bikes said he will send one for free,anyone know how to fit it,if i have to remove the handlebar grip how do i do that? you might have guest i am a complete novice at this to say the least!