Former Star player Weir, who has represented the club in the Argyll Select as a player, and who took the reins as team manager in 2018, cited the demands of the role in stepping aside just a week before the team prepares to venture into its first season in the newly formed Scottish Premier AFA.
Star will play in the new league's top tier - with the prospect of two mouth-watering derby games against Argyll rivals Oban Saints - after Weir guided his talented young Star squad to second place in the 2022-23 Scottish AFL, missing out on the league by a single point, and reaching its league cup final, the Jimmy Marshall Cup.
Speaking on Monday evening, Colin explained: "I have decided to step down as manager of the team.
"I know that the timing isn't great with the start of the season this week (Saturday August 5) but I felt I needed a break from the role to recharge given the demands of it for the past several years.
"It has been a huge commitment, and perhaps in future seasons it will be a possibility again, but I wish the club every success on the pitch and in finding someone to take the team forward for the new season."
A club spokesperson said: "Lochgilphead Red Star would like to place on record a massive thank-you to Colin and [Colin's brother] Andy Weir who both took up the reins in 2018 and have had to endure some testing times during their tenure, with a total rebuild of the squad and team.
"They have produced an excellent young dynamic team during the past few years, who have excelled beyond their years, and came so close last season to a league and cup double.
"Colin has been instrumental in keeping the club moving forward, and will be a massive loss not only to the club, but to the players he worked with week in, week out.
"We would like to wish him all the very best for the future."
Red Star open their league campaign tomorrow (Saturday) with a home game to Castlemilk, kick off 2pm at the Joint Campus.
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