98 recon

i just picked up a recon for a hell of a deal all because the jets where plugged solid. but besides that is runs a little funny it back fires offten and it dosn't like to idle but when it is fully warm it revs really high but when its cold and the same setting it will barely stay running. im thinking it may be a low compression but have not checked it yet ( should i ) and is this thing supposed to have a clutch? or is the left lever only for going into reverse. thanks.