Author Topic: CB500 master cylinder fluid return hole problem  (Read 18823 times)

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Offline jvandyke

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Re: CB500 master cylinder fluid return hole problem
« Reply #25 on: May 17, 2011, 09:30:18 AM »
SohRon: WOW what camera and setting was it on.
                           Thanks Ken
+1!!
I just wonder what the orientation of the reservoir is, I read the small is closer to the fluid outlet so I'll I'm guessing I'll find the little hole there somewhere.  Anyone else guilty of 'virtual wrenching" while at work and wasting time trying to figure stuff out in absentia from the bike whereas 1 minute with the machine in front of you would answer the question?  I am guilty of this.  Sorry.
1972 CB500, 7500 miles, in family since '73

Offline Viktor.J

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Re: CB500 master cylinder fluid return hole problem
« Reply #26 on: July 19, 2013, 10:59:37 AM »
Is this doable while The MC is mounted on the bike with brakefluid ? "just" clean the hole with a guitar string or thin needle from the underside ?
I would hate to change the brakefluid and bleed the brakes again (did it a few month ago).

Please ! Take a look and give me feedback in my project thread, its much needed :)
http://forums.sohc4.net/index.php?topic=112745.0

Honda CB750 K2

Offline crazypj

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Re: CB500 master cylinder fluid return hole problem
« Reply #27 on: July 19, 2013, 11:09:21 AM »
IIRC the hole is about 0.015", I use a pin vice and 0.4mm drill to clean them
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Offline LesterPiglet

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Re: CB500 master cylinder fluid return hole problem
« Reply #28 on: July 19, 2013, 11:11:00 AM »
Speaking as a native of the Northern bit of UK (NOT Scotland)

There's Nowt wrong with clogs lad, usefull for dancin' an' ankle tappin!!
I wouldn't like one in the hole though.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Draw and drawer. Could care less/couldn't care less. Bought/brought FFS.


Les Ross.            Certified by a Professional

Offline LesterPiglet

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Re: CB500 master cylinder fluid return hole problem
« Reply #29 on: July 19, 2013, 11:17:17 AM »
Easily done with the MC installed. But if the hole is full of crap you're going to need to change the fluid anyhoo. Clean/poke from inside the MC.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Draw and drawer. Could care less/couldn't care less. Bought/brought FFS.


Les Ross.            Certified by a Professional

Offline Viktor.J

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Re: CB500 master cylinder fluid return hole problem
« Reply #30 on: July 29, 2013, 10:19:24 AM »
I seem to have a similar problem.. Is this the same on a CB750 K2 ?

My pistons aren't retracting. I removed the passive side and the brakepads and when I moved the lever the piston moved out as it should. But when I removed it It's impossible to push the piston back in, this is the same for both calipers (dual discs) and they where cleaned and new seals this winter. Ill try to aply a pressure then loosen the banjobolt and se if it retracts, by what I have read, that would indicate that the MC needs a overlook hence not releasing the preassure.

but where the f*ck are these small holes ? I look and look but can't find them anywhere. So if someone could provide a picture of the location of them that would be great.
« Last Edit: July 29, 2013, 10:26:58 AM by Viktor.J »
Please ! Take a look and give me feedback in my project thread, its much needed :)
http://forums.sohc4.net/index.php?topic=112745.0

Honda CB750 K2

Offline LesterPiglet

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Re: CB500 master cylinder fluid return hole problem
« Reply #31 on: July 29, 2013, 11:19:37 AM »
That picture previously posted is as if you are sitting on the bike, so the holes are towards the front of the MC.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Draw and drawer. Could care less/couldn't care less. Bought/brought FFS.


Les Ross.            Certified by a Professional

Offline SohRon

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Re: CB500 master cylinder fluid return hole problem
« Reply #32 on: July 29, 2013, 11:38:27 AM »
Here's a larger pic detailing the holes; might help you orient yourself a bit better...




Camera is a Canon SX110IS, BTW.
« Last Edit: July 29, 2013, 11:42:22 AM by SohRon »
"He slipped back down the alley with some roly-poly little bat-faced girl..."

Assembling my '74 CB550: http://forums.sohc4.net/index.php?topic=86697.0
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Offline Viktor.J

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Re: CB500 master cylinder fluid return hole problem
« Reply #33 on: July 29, 2013, 11:58:36 AM »
Ok, now I see, I read somewhere "at the banjo" hence I now see why I didn't find them :)

Actually I removed everything as mentioned, everyting moved fine. Re-torqued the disc (it was not 100% tightened at some places) and installed everything again. Now it works like a clock :) No sound at all, and Im able to look the front wheel cause a screaming tire instead of breakes :D
Please ! Take a look and give me feedback in my project thread, its much needed :)
http://forums.sohc4.net/index.php?topic=112745.0

Honda CB750 K2