Author Topic: Front Brake Caliper piston size -78' CB550k  (Read 914 times)

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Offline redrider736

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Front Brake Caliper piston size -78' CB550k
« on: November 08, 2013, 08:40:26 pm »
My front brakes are in need of some TLC. Planning to re-build the OEM, add on SS lines and add a new master cylinder unit.. I don't understand what they mean when looking at different styles of master cylinders units ("for 5/8 or 1/2 or 14mm piston) ??

Do I need to match up the size of the "caliper piston" size in my Caliper to the new master cylinder that I choose ??
http://www.dimecitycycles.com/vintage-caferacer-cafe-racer-bobber-brat-chopper-custom-motorcycle-brake-parts-black-aluminum-nissin-hydraulic-front-shorty-brake-master-cylinder-perch-lever-kit-17-653b.html
« Last Edit: November 08, 2013, 08:50:11 pm by redrider736 »
78' CB550k (Not Run'n / Basket Case Project)
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Offline bryanj

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Re: Front Brake Caliper piston size -78' CB550k
« Reply #1 on: November 08, 2013, 11:14:42 pm »
You can't change the caliper piston size without changing the caliper, which means a new mount which probably wont fit your forks!

All the single caliper masters were 14mm if you want twin discs go 18mm(same as gold wing)
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 redrider736

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Re: Front Brake Caliper piston size -78' CB550k
« Reply #2 on: November 09, 2013, 04:41:28 am »
Sorry, I just want to know what is the size of the stock OEM caliper piston on my CB550k ? Not changing the the Rotor or Caliper.
 I am just not understanding what they mean when looking at new master cylinder units like the link above from dimecity that one is for a "1/2 inch piston"
« Last Edit: November 09, 2013, 04:47:13 am by redrider736 »
78' CB550k (Not Run'n / Basket Case Project)
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Offline wowbagger

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Re: Front Brake Caliper piston size -78' CB550k
« Reply #3 on: November 09, 2013, 05:08:54 am »
The piston is 14mm across. If yours is pitted and can't be polished smooth check out David Silver Spares or 4into1.com for a replacement poston

Offline becken

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Re: Front Brake Caliper piston size -78' CB550k
« Reply #4 on: November 09, 2013, 05:29:40 am »
1976 CB550F bought new
1981 CM400A wife bought new
2004 GL1800

Offline bryanj

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Re: Front Brake Caliper piston size -78' CB550k
« Reply #5 on: November 09, 2013, 08:20:32 am »
The CALIPER piston size bears no relation to the standard MASTERCYLINDER size whic is 14mm
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 redrider736

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« Last Edit: November 09, 2013, 12:47:57 pm by redrider736 »
78' CB550k (Not Run'n / Basket Case Project)
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Offline steakCB550K

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Re: Front Brake Caliper piston size -78' CB550k
« Reply #7 on: November 09, 2013, 04:02:47 pm »
Just a heads up, sohc4.net user Godffery in WI sells replacement caliper pistons.  Good dude.
Check it out.
http://www.vinmoto.org/gallery/v/VinMoto-Garage/album03/Godfferys-Garage-123/95/PHENOLIC+Replacement+brake+Caliper+piston/
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Offline scottly

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Re: Front Brake Caliper piston size -78' CB550k
« Reply #8 on: November 09, 2013, 05:23:53 pm »
Sorry, I just want to know what is the size of the stock OEM caliper piston on my CB550k ?
The stock 550 caliper piston is 38mm in diameter.
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