Author Topic: CB550: uneven braking  (Read 825 times)

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Offline Franky

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CB550: uneven braking
« on: February 25, 2014, 11:12:06 AM »
When I use the rear brake, the braking action is not smooth and constant. Instead it alternates in a wobbly kind of way: hard braking, less-hard breaking, hard breaking, etc. the sensation increases the harder I brake. I had a look at the pads and they seem evenly worn.

any ideas?
1974 Honda CB360T Stock
1974 Honda CB550 K0 Stock
1977 Honda CB550 K3 Cafe - never ending build :)
1988 Honda Dax ST50 Cafe
1997 Honda Benly 50S Stock

Check out my "Yamaha R6 fork on a CB550 made easy" thread:
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Offline flybox1

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Re: CB550: uneven braking
« Reply #1 on: February 25, 2014, 11:41:56 AM »
That pulsating sensation would lead me first to cleaning the brake drum or rotor surface.
rub it down with fine emery paper, then clean it really well with spray brake parts cleaner and/or compressed air. 
wear some sort of mask as ingesting the brake dust isn't a good thing.
cross contamination of the brake pads is possible. 
if you reuse contaminated pads, the problem might reappear.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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Offline calj737

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Re: CB550: uneven braking
« Reply #2 on: February 25, 2014, 11:45:17 AM »
Also, do a comprehensive check on your wheel bearings. The braking pressure could easily be causing the wheel to wobble that is otherwise not noticed. Is your wheel also aligned properly left-to-right? Do also check your swing arm bushings and be sure your shocks are fully tightened.

If you've checked your pads and the brake surface, then the problem lies somewhere else as described above.
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'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline LesterPiglet

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Re: CB550: uneven braking
« Reply #3 on: February 25, 2014, 12:16:27 PM »
Liner is susceptible to cracking on 550's. Check it carefully.
'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.


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Offline dave500

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Re: CB550: uneven braking
« Reply #4 on: February 25, 2014, 12:50:03 PM »
gday franky,the brake hub may be out of round,does the pedal pulse up and down a little bit at the same time?

Offline Franky

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Re: CB550: uneven braking
« Reply #5 on: February 26, 2014, 05:40:51 AM »
I'll take apart the (drum) brake and follow your suggestions. I have a new set of bearings I need to fit, so that will rule out the possiblility that they are at fault.

Hi Dave: No, the pedal doesn't seem to move.
1974 Honda CB360T Stock
1974 Honda CB550 K0 Stock
1977 Honda CB550 K3 Cafe - never ending build :)
1988 Honda Dax ST50 Cafe
1997 Honda Benly 50S Stock

Check out my "Yamaha R6 fork on a CB550 made easy" thread:
http://forums.sohc4.net/index.php?topic=118983.0;all

Offline calj737

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Re: CB550: uneven braking
« Reply #6 on: February 26, 2014, 05:46:14 AM »
Since you'll be pulling the wheel, that will provide you an excellent opportunity during re-assembly to make certain all the alignment and fasteners are properly tightened. Do also check your swing arm bushings while the rear is apart.

A last bit: if you have the means, check the rear wheel for "true". Pop the axle onto a make-shift stand, slide wheel over the axle and measure for runout. Who knows, wouldn't hurt to cross that off the list when it's so easy to verify.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Franky

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Re: CB550: uneven braking
« Reply #7 on: February 26, 2014, 09:36:11 AM »
Thanks calj737. I actually have a set of new spokes too. I have recently build a new front wheel (http://forums.sohc4.net/index.php?topic=118983.0;all) , so maybe I should go all the way and get that done too... Just a few too many projects these days :-)
1974 Honda CB360T Stock
1974 Honda CB550 K0 Stock
1977 Honda CB550 K3 Cafe - never ending build :)
1988 Honda Dax ST50 Cafe
1997 Honda Benly 50S Stock

Check out my "Yamaha R6 fork on a CB550 made easy" thread:
http://forums.sohc4.net/index.php?topic=118983.0;all

Offline strynboen

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Re: CB550: uneven braking
« Reply #8 on: February 26, 2014, 10:28:46 AM »
mine hub vas cracket total..aluminium korodes inside and press the cast irom ring to break

there are 2 types of hubs. for the 1978 k3.....(.f type and k type.).i got a vront type home from germany

i have a reserve plan..to drill the brakecast matrial aut...and chrimp a cast iron drum in and turn it aut to spec....and safe it aganst turning vith some brass bolts through the matrial..think a drum brake from a littel car trailer can delevre the parts
« Last Edit: February 26, 2014, 12:38:08 PM by strynboen »
i kan not speak english/but trying!!
http://forums.sohc4.net/index.php?topic=60973.0
http://forums.sohc4.net/index.php?topic=144758.0
i hate all this v-w.... vords

Offline LesterPiglet

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Re: CB550: uneven braking
« Reply #9 on: February 26, 2014, 10:52:21 AM »
A popular substitute in the UK was a drum from a Morris Minor.
'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 strynboen

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Re: CB550: uneven braking
« Reply #10 on: February 26, 2014, 12:35:09 PM »
ha.... ;D a bit hard to find in today"s denmark... ;)..but like to hear the idea has be done before...my other idea vas to make a hub instrt to konverse to disc mounting..but to find a small disc/kaliber mounting..(this 750 sets are massive)..but spoken hveel small disc make the  parts marked small
« Last Edit: February 26, 2014, 12:38:54 PM by strynboen »
i kan not speak english/but trying!!
http://forums.sohc4.net/index.php?topic=60973.0
http://forums.sohc4.net/index.php?topic=144758.0
i hate all this v-w.... vords

Offline LesterPiglet

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Re: CB550: uneven braking
« Reply #11 on: February 26, 2014, 12:46:56 PM »
 ;D ;D http://www.morrisminorspares.net/shop_item.php?ID=1525
That's a 7", there is 8" as well. I'm not sure what you need.
'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 MoMo

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Re: CB550: uneven braking
« Reply #12 on: February 26, 2014, 01:19:44 PM »

also, check the chain for tight and loose areas-that could cause hop when rear brakes are applied...Larry

Offline calj737

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Re: CB550: uneven braking
« Reply #13 on: February 26, 2014, 02:28:46 PM »
Another good idea!
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline seanbarney41

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Re: CB550: uneven braking
« Reply #14 on: February 26, 2014, 06:29:40 PM »
How much have you ridden the bike?  I have had similar symptoms with bikes that have sat for a very long time.  It eventually smoothed out on it's own through use.  ...not the safest way to do it.
If it works good, it looks good...