Done 350ish bales of barley without a problem then it started to trip randomly, maybe every 10 bales. Sometimes seems to trip correctly but then trip again straight away..... managed to catch it as the computer has registered the fault so not damaged any billhooks. Guessing electrics are ok as it's registering the fault and measuring bale length correct as it's baling. I'm happy the electric motor side of the trip arm as I put a new spring on the cam and a new nylon plate as the spring had gone very poor and started to fail in the last field last year. Can't see any other problem except May be I greased the cam the other end a bit much and dust stuck to it so just cleaned it off now as shown in pictures, any suggestions before I try again next dry day?