Front Rotors... Does size really matter?

ST Gui

240Robert
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My 750-K4 came with a single disc and caliper in the front. There was no perceptible change in handling when I added the second disc and caliper. I also revered the mounting so the calipers were behind the fork legs. The discs were drilled as well. Looked very trick in its day. But there was never any twerk factor to consider.
 

JimSTer

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Thanks to all! I believe we have found the answer. Occam's Rotor! Have spent time pondering anti dive linkage/travel, caliper, etc All along it was simply the wrong rotor. Can anyone recommend a domestic source for the correct rotor? Here in Columbus I might be able to get one from Iron Pony, currently priced at $225. Since the right rotor is still 4.95mm thick, there seems to be plenty of life left. Would it be bad form to just replace the incorrectly sized rotor or does one always replace both? Thanks again!!
I have a front left non ABS rotor that is certainly useable. I bought a set (used) several years ago and replaced the right rotor as it was warped. I believe the left rotor was not replaced and it is still hanging on my work bench.
If you want to try it, just pay the shipping and I'll send it to you.
 

Uncle Phil

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My 750-K4 came with a single disc and caliper in the front. There was no perceptible change in handling when I added the second disc and caliper. I also revered the mounting so the calipers were behind the fork legs. The discs were drilled as well. Looked very trick in its day. But there was never any twerk factor to consider.
I wouldn't have expected it to as it was designed that way and adding another caliper shouldn't helped. I guess somebody could yank one of their rotors off and try to stop and what happens. ;-) I just happened to install a pad on the wrong side of the disc (my poor eyesight and poor lighting during installation) and I can tell you from that experience there was some noticeable pull to one side, hence my comment. ;-) I'm also surprised that the caliper pistons on short rotor side didn't push way out or the brake pads come loose. But then I'm surprised pretty easily .... :D
 

ST Gui

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I'm also surprised that the caliper pistons on short rotor side didn't push way out or the brake pads come loose. But then I'm surprised pretty easily ....
LOL! Given the strength of the brake pad backing plate and that at least half of it was still on the disc I'm not surprised that the pistons stayed put. I would think they'd have to be significantly above the edge of the rotor and that the pad material would have to be worn enough to allow the pads to be canted within the caliper before the pistons were a problem. But I'm just guessing.
 
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