Author Topic: 550k1 Brake caliper question  (Read 364 times)

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Offline JDrider

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550k1 Brake caliper question
« on: July 13, 2023, 04:54:56 AM »
1975 cb550k1
I got the bike last year and it had an aftermarket front brake caliper installed (M MATI?).
It seems relatively new, but the braking isnt working quite right.
I rebuilt the master cylinder and replaced all brake lines.

My question is, is it better to find and buy an original brake caliper and rebuild it?
or try rebuilding the aftermarket? Or buy another aftermarket?
Thanks,
« Last Edit: July 13, 2023, 04:57:03 AM by JDrider »
JD
1975 CB550K1

Online bryanj

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Re: 550k1 Brake caliper question
« Reply #1 on: July 13, 2023, 05:30:18 AM »
What are you comparing it to, its a 50+ year old design and nowhere near as good as modern, plus what pads are you using
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline JDrider

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Re: 550k1 Brake caliper question
« Reply #2 on: July 13, 2023, 05:36:00 AM »
What are you comparing it to, its a 50+ year old design and nowhere near as good as modern, plus what pads are you using

I trying to figure out if the problem is that i have an aftermarket caliper that isnt as good as the original ones
or if new aftermarket calipers are good and I just need to rebuild it.
I will get new brake pads also.
JD
1975 CB550K1

Online bryanj

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Re: 550k1 Brake caliper question
« Reply #3 on: July 13, 2023, 07:32:36 AM »
Nothing wrong with the M Mati calipers, all a caliper does is push the pads onto the disc.
As long as the master bore is standard, the caliper bore standard, lines not blocked, pivot pin on bracket free and greased with adjuster set right you will get the best you can out of the pads
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline Shtonecb500

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Re: 550k1 Brake caliper question
« Reply #4 on: July 13, 2023, 07:37:54 AM »
if the piston and o ring in the caliper is good then I would look at the the rebuilt MC as the culprit since you've replaced lines. Ive rebuilt many MC with no positive result and just had to replace it.
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Offline JDrider

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Re: 550k1 Brake caliper question
« Reply #5 on: July 13, 2023, 07:58:55 AM »
Nothing wrong with the M Mati calipers, all a caliper does is push the pads onto the disc.
As long as the master bore is standard, the caliper bore standard, lines not blocked, pivot pin on bracket free and greased with adjuster set right you will get the best you can out of the pads

Now you have me wondering about the pivot, I did replace that screw and spring.
JD
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Online bryanj

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Re: 550k1 Brake caliper question
« Reply #6 on: July 13, 2023, 09:28:43 AM »
Unbolt the two caliper bolts and see if the alloy bracketi the middle of the two halves moves easily
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!