I have Longboards and Tektro Silver (not sure what "R" number those equate to)
brakes on my orange Ram, and it works great with 28m Paselas. I've also put on
32mm Schwalbe Marathons for a trip on the C&O Towpath, which worked fine too.
The Schwalbes seemed a little tight, but I had no problems
Ryan
Some have installed longboards, or SKS fenders on their Ram but there are
also many who were successful in installing metal fenders.
There are a couple things one can do to improve the clearance for fenders.
What brakes do you have? The stock Shimano brakes are nice at stopping but
the Tekt