Sunday, November 28, 2010
Continuing on with the thoughts on a gravel grinder specific bike from yesterday's post. I laid out the basic geometry of the bike as I see it, now I want to get into some things that are maybe a bit strange, and certainly specific to my wants and desires.
The first thing that needs to be covered is the drop out question. I've seen many a Trans Iowa and Dirty Kanza 200 ride come to a screeching halt due to a rear derailleur getting ripped off, a replaceable drop breaking, or a integral hangar getting twisted beyond repair in the field. This would be less of an issue if one could more easily convert to a single speed set up in the field. This would be a workable solution if track ends, (with a derailleur hangar), or forward facing horizontal drop outs were used. Plus, then I could single speed this rig, if and when I wanted. (And I might want that) The other workable solution here would be to go with a split shell eccentric bottom bracket, but that is somewhat off the radar due to a brake idea Ben Witt and I have.....
Yep! Here is where we go off the beaten path. The Paul Racer Brake is a replica of the old Mafac Racer brake that was in use years ago. As you can see from the photo, it has loads of clearance and it is quite powerful. What we are considering is putting it under the chain stays. Why?
We feel it will allow for an unencumbered seat stay which, since it won't have to resist braking forces, could perhaps be a bit more "flexible" and give a more comfortable ride over the long haul. Not to mention the fact that it will look sleek as all get out.
Yes, there are some technical challenges to fitting all that under there and have the cable work it. This may not happen in the end, at which time we would default to cantilevers, or at least I would. (Or maybe we'd just put the racer brakes on the seat stays after all, who knows!) Anyway, it will be a fun exercise to see if we could possibly pull it all off.
That's all for now. Next weekend there will be a few beers drank and some ideas batted around for this project. I may have some more to report later. Stay tuned....