I would assume that it is in the same place for the PH1 as it is for the PH2.
This is where it is on PH2, so look in the same place (its the same engine, just cable throttle on PH1 and fly by wire throttle on PH2.
Remove the airbox, then look in the space, its on the left, just above the gearbox. See the thread below for pictures. I've had the same thing, I did what this thread suggested, cleaned it up, its had a couple of little 'hiccups' since, but much better overall. You don't need to be too mechanically minded to do it also.
http://www.cliosport.net/forum/showt...&highlight=tdc