Topic: Rear Brake Shoe Plate Stress Cracking

[Blackhorse]

I spent the weekend cleaning, sanding and polishing the rear Brake Shoe Plate from my '75 CB550 and noticed some stress cracking around the pin bosses and and the cam boss. They are .125 to .250 in length and less than a 1/16 wide. Is this normal for a 35 year old bike or did this thing see some major braking trauma. I'd take pictures, but I don't think the cracks will show up very well. They don't look serious enough to concern my self with failure and I use my front mostly anyway. I just thought it was interesting.

[steam-powered man]

these pins are steel while the plate is aluminum.  possibly some serious overheating of the brake unit led to cracks at the interface of the components due to the differential in coefficient of expansion between materials?  or maybe a PO was using a bfh and drift to remove shoes.   

[bucky katt]

to keep the cracks from going any farther drill holes at either end of the cracks, no need for giant holes, maybe 1/16th or so