I'm building my Habanero Titanium Team Issue frame to be my summer commuter. It has no braze-ons that I can use. So, I'm looking at p-clamps and perhaps a seatpost clamp with rack mounts. I'll be mounting a Tubus Carry Titanium rack. It appears that the two attachment rods for the rack will need to be bent at a fairly steep angle to reach the seatpost clamp rack mounts. So, here's my question - am I reducing the load (weight) I can carry with such a setup? Since I often stop to do some food and beverage shopping on my commute home, I want to make sure I'm still able to carry about 30 lbs. Oh, the reason I'm considering this at all is because of the very tight clearance I'd have with p-clamps at the top. I've got SKS RaceBlade Longs on it. And, there's not a whole lot of room. Thoughts....

I rode for several years with a rear rack mounted on a seatpost mount like this on an aluminum cannondale. Never had any problems commuting and carrying regularly 10-20 lbs. Sometimes more.

Eventually, after taking the rack off a few times, I wrecked the threads on the seatpost clamp.