Author Topic: CB750 drum brake woes  (Read 3097 times)

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Offline hondaface75

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CB750 drum brake woes
« on: May 09, 2010, 08:52:03 AM »
Ive got a 75cb750k with a entirely stock rear drum brake setup, with new shoes, bearings and a henryabe wheel for the bike. All works fairly well until I am on a hill using my rear brake. Itll roll back a bit and then catch. I'm assuming this is because of the single leading shoe design? When off on my way again, Ill go to use the rear brake in the opposite direction (forward) and itll not do anything until what seems like the whole system shifts back the other way. Pretty audible noise from that and a strong feeling in the brake pedal from the engagement. Is this normal? Or is something sticking that shouldnt be?

Offline mystic_1

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Re: CB750 drum brake woes
« Reply #1 on: May 09, 2010, 09:23:24 AM »
Check the rear brake torque arm, the flat brace that connects the rear brake panel to the front of the swingarm and keeps it from rotating.

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Offline BobbyR

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Re: CB750 drum brake woes
« Reply #2 on: May 09, 2010, 09:51:06 AM »
+1 on that. You should not feel what you are. The mechanism in the drum is so simple, there is nothing to really go wrong.
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Offline 754

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Re: CB750 drum brake woes
« Reply #3 on: May 09, 2010, 10:15:22 AM »
Put the proper SHOULDER BOLTS, in both ends of the torque arm...
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Offline hondaface75

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Re: CB750 drum brake woes
« Reply #4 on: May 09, 2010, 10:34:00 AM »
K, ill check the bolts holding the arm on and see if there is any play. Shoulder bolts, these are the ones with a thicker shaft in the middle without threads yes?

Offline 754

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Re: CB750 drum brake woes
« Reply #5 on: May 09, 2010, 10:38:24 AM »
Correct, there are maybe 2 steps, then a thread smaller than that with a hole for a cotter.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Bodi

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Re: CB750 drum brake woes
« Reply #6 on: May 09, 2010, 01:17:27 PM »
I've seen a few torque arms where the holes have stretched out to oval and even with the correct bolt there's slack. The slack does just what you describe - after braking in reverse you have a problem next time you use it going forward. The braking suddenly gets a lot stronger with a loudish CLUNK.