Originally Posted by
etherhuffer
Interesting. I am going to measure my bikes, then head to Recycled Cycles and measure a few there too. The consensus so far has been 165mm most common followed by 180mm. Thanks for measuring, more data is always useful.
Do pay attention to the rack's aspect to all this. Many (and the "grandfather" of modern low riders, Blackburn's FL-1) had the distance between the lower/dropout mounting hole a fixed distance from the upper/mid blade mount hole/slot. This fixed distance limits rack alignment WRT the bag hanging down vertically. Look at how the rack sits and thus how/where the bag has to also be. Perhaps bring your own pannier to check.
The other aspect not yet mentioned and not generally a big deal is how high off the road is that upper/midblade mount. Or more to the point, how close to the ground are the pannier bottoms? One of the reasons why I wanted my rack's horizontal rail to be high up the fork is the bike is a 559 ISO w/ 1.5 tires. Everything else the same a 559 VS 622 bike will see the pannier bottoms about 2.4" lower down to the road. Even with the higher location on my bike I have still rubbed the pannier bottoms on the road when the road has a lot of crowning (when u turning) and on really tight/banked switchbacks. This is why before "bikepacking" bags became "the way" off road we used classic above the tire racks. Andy
I should add that the road rub was with by big panniers, Arkel GT-18, which are rather large for a front low mounted bag at 2200ci a pair