Hi guys, I recently restored this long neglected 1979 Univega Sportour into a quite rideable and fun cross bike. so far I've only ridden it on unpaved canal paths in the city. It's got 27 inch rims so I put some great 27in x 35mm Cross-Terra tires on and converted the old 5 speed downtubes into a 7-speed indexed brifter setup (thank goodness for the new Shimano Tourney line bringing ancient bikes into modern times!). I'm what I'd consider a serious road cyclist for many years, but I got the gravel bug and have some concerns about the brakes and questions about gearing.
How do rim brakes hold up on extended gravel travels? I'm well aware of the diminished stopping power of rim brakes in wet/muddy conditions. While dirt roads here in southern Arizona are dry most of the year, there is always the off chance of getting into some mud in the monsoon season; the tight clearances of rim brakes also concern me when it comes to getting rocks and dirt clods gunked up into the wheel. Am I just imagining these concerns or are rim brakes adequate for gravel grinding and light duty gravel touring?
2nd, I'm thinking about switching out the old 52x42 road chainrings for something more appropriate in the cross range of 46x34. Because the old Campy crank uses an outdated 18mm BCD. I can't just go out and buy new chainrings so the whole thing has to be replaced. It seems like cranks specifically marketed to cross bikes are rather expensive, $150+ and I don't want to spend so much to upgrade a very old bike. What is the possibility of taking a shimano mtb triple and converting it to a double? If I have a shimano double road shifter/derailleur right now, will it work as is to take the granny ring off a mtb triple and just set the limit stop at the middle ring - or will there be an issue with mismatched indexing and/or inadequate derailleur throw? Thanks!
univega sportour cross conversion - front shifter.jpgunivega sportour cross conversion - crank-frontder.jpgunivega sportour cross conversion.jpg