I am pretty new to cycling and have recently purchases a Giant TCR which although is in beautiful condition (2nd Hand) the right arm has no thread left in it. The bike was fairly discounted as I need to replace that part but the rest is lovely, recent service, new chain, cables etc.
My question is that the bike has a Shimano Tiagra 4503 triple Crankset as per picture. The rings on my current one are spot on, it really is only the arm. Anyways I ordered a replacement which is on its way, though it comes as a set. both arms, rings etc. Would it be possible to simply take the right arm off via those allen key bolts and replace with other arm and just leave current rings on (So that in month down the line i have a spare set of rings )? I have not tried to take aprt as dont want to incase something goes worng or it should not be done etc,
Any help much appriciated.