Originally Posted by Daily Commute
There are some things that reasonable people can disagree about, but I don't think this is one of them. Put it on the rear.
If you put it on the front only, breaking would be dangerous--it would encourage your rear wheel to flip over the front. Very bad.
On the back, the panniers weigh down the rear wheel, which increases stopping efficiency.
Edited to correct type-o.
I'll be one of those reasonable people who will disagree with you on this. A loaded front fork is no more dangerous than an unloaded front wheel with respect to braking. Adding even 30+ pounds to the front wheel is not a problem. The bulk of the weight of the bike is on the rear wheel in all normal situations anyway (the rider mass is closer to the rear wheel). Although I haven't (and won't
) do the math, I don't think any amount of weight added to the front wheel using a low-rider rack could contribute to pitch over using any brake system you might want to suggest. There is no moment of angular momentum that could be imparted to the pannier load because the pannier sits over the pivot point.
I have used lowriders and panniers on the front of many bikes without loads other than myself on the rear wheel and pitch over is just not a problem. In fact, the steering is dampened and control of the bike is enhanced using front bags only.