Originally Posted by
HillRider
Funny but I had just the opposite experience with the Avid SD7 V-brakes on my Cross Check. The OEM holders with both the OEM pads and with Kool Stop Salmon replacement pads squealed like mad. I toed them in, I toed them out, I set them flat, I scrubbed the rims, I sanded the pads, I greased the mounting posts, I tightened the mounting bolts beyond tight,....nothing helped.
Squeal is a complex phenomenon which depends on the friction property of the pad and the rigidity of the system along with some other variables. New KoolStop shoes are some what more prone to squeal than many others because of the raised rear corner. If that's filed (or worn) off they squeal much less.
Even when everything is good, the exact friction properties can change. My commuter's brakes are very weather sensitive. They don't normally squeal when dry or wet. But the day after a rain, or if the humidity is fairly high they'll squeal like crazy for a while until things settle back to normal.
In any case, I was more concerned about the height of the shoes. If you look at the OPs photos, you'll see that the arms are already inboard of top dead center, so the shoes are already arcing down as they close. There's a limit to how much of that is OK (almost all brakes do it to an extent) before the brake's performance suffers significantly.