I have a Marin Bolinas Ridge 7.1, I am not happy with the front large chain ring size, I mainly ride on the road, and have an extremely limited budget. I would take it to the LBS, however, I believe that would cost at least an hours time just to find out what it is that I have.
More so than anything, I am trying to find out the specs as the ones on their website only list it as forged. I have determined that it is a 110 BCD with a tapered square. An email to the company revealed that they are not sure what is in it, and possibly riveted chain ring(s). (Bolinas Ridge 7.1 ). I also do not have the tools to pull it apart for a better idea of what I should be looking for. If anyone has changed one of these I would like to find out a lot more.
edit- original teeth are 42, i was looking to go either 48 or 50.
p.s.I have since learned that it should be a regular square taper, so I will be getting another crank. At that point, I should be able to figure out the ring.
Thank you for your interest.