Hay man nothing to worry about, we all experience this, when you are sexually aroused ar your body is preparing for sed arousal you produce pre ejaculate (precum) this serves several prppouses, lubrication, clearing of urea, cleaning of ducts prior to ejaculation, and lubricating your duct, ive always produced lots of this, presuming its a clear sticky and elastic like material i think its normal, I get this a lot because im very horny and sexual. just thinking of sex or looking at pics does it to me. Nothing to be worried about except added carbon footprint for washing extra jocks.
Hope this helped
bigirishman