Author Topic: CB550K3 Rear brake plate spacer  (Read 229 times)

Offline Raymond_Y

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CB550K3 Rear brake plate spacer
« on: February 09, 2019, 05:18:46 PM »
Can anyone advise how wide the rear wheel, brake plate side, spacer is on a CB550K3.  It would appear I have a CB550K3 brake plate and a CB500K0 spacer and it looks as if the CB550K3 brake plate has a wider boss than the CB550K0 brake plate, as my spacer is about 10 / 12mm too wide.  All other parts appear to be common.  If I can find out how wide the spacer needs to be I can make one.

Many thanks

Raymond
Raymond

1971 CB500K0 (being rebuilt)
1977 CB550K3 (bases for future 650 cafe racer)
Q plate CB550 in bits

Offline Trigger

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Re: CB550K3 Rear brake plate spacer
« Reply #1 on: February 09, 2019, 06:44:03 PM »
Wide ? Don't you mean too long?
You mention two brake plates here, K3 and 550K0. The 323 spacer is longer than the 404 and the swinging arm is different on the K3 and the chain adjusters are a different thickness. Also you have a 323 hub and a 404 hub  ;)
So, are you trying to fit a K3 plate on to what swinging arm with what sort of chain adjusters ?

Offline Raymond_Y

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Re: CB550K3 Rear brake plate spacer
« Reply #2 on: February 09, 2019, 07:18:28 PM »
Yes, I do mean long.  I did not appreciate that the swingarms were different.  I suspect I have both a CB500K0 and a CB550K3 one, but I do not know which one is fitted.  What are the differences?  I suspect what I need to do is fit a 404 spacer.  Do you know how long a 404 spacer is?

Many thanks

Raymond
Raymond

1971 CB500K0 (being rebuilt)
1977 CB550K3 (bases for future 650 cafe racer)
Q plate CB550 in bits

Offline Trigger

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Re: CB550K3 Rear brake plate spacer
« Reply #3 on: February 09, 2019, 07:29:07 PM »
I can't remember what the difference was between the swinging arms but, i recall that there was one. The K3 spacer is 38mm off the top of my head. Why not fit everything together and then measure the gap ?

Sorry the chain adjusters are not a different thickness, i was thinking about the 550 F adjusters then  ::)
« Last Edit: February 09, 2019, 07:32:31 PM by Trigger »

Offline Raymond_Y

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Re: CB550K3 Rear brake plate spacer
« Reply #4 on: February 09, 2019, 08:28:05 PM »
Thanks Trigger, that would be about right I think, looking at the gap I have with no spacer fitted.  My problem is I bought two bikes, a 1971 CB500K0 and a 1977 CB550K3 in bits and the parts were mixed up.  I have even have some 250 or 400 Super Dream bits.

Many thanks

Raymond
Raymond

1971 CB500K0 (being rebuilt)
1977 CB550K3 (bases for future 650 cafe racer)
Q plate CB550 in bits

Offline 3scs

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Re: CB550K3 Rear brake plate spacer
« Reply #5 on: February 09, 2019, 09:54:47 PM »
This is the k3 spacer 32mm I had a similar problem had an f swingarm originally fitted to a k3 but there is a spacer in the other side which was also different

Offline matthewmosse

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Re: CB550K3 Rear brake plate spacer
« Reply #6 on: February 09, 2019, 10:49:29 PM »
If theres mix and match going on, some back plates bind up once tightened because of outside diameter differences on the back plate and wheel hub. Only apparent when tightening the spindle. Been 15+ years since I encountered that so cannt remember the details - if was before I knew of this forum or had a lathe and measuring kit or Ebay mastery. I think I resolved it by grinding the inner lip of a back plate down. There days I'd just sell the 'wrong' part and buy the right one, or do things nearer on a lathe.
Got a 500/4 with rust and a sidecar and loadsa bits. nice and original and been round the clock

Offline Oddjob

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Re: CB550K3 Rear brake plate spacer
« Reply #7 on: February 09, 2019, 11:42:05 PM »
I seem to recall that the differences between the 500K and the 550K were that the swinging arm bushes on the 500 were metal but were fibre on the 550, also the 550 has a grease nipple on the swinging arm pivot tube, the 500 had them on the swinging arm spindle.
Don't play stupid with me, I'm better at it

Offline Raymond_Y

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Re: CB550K3 Rear brake plate spacer
« Reply #8 on: February 10, 2019, 08:54:31 AM »
Many thanks for all the input.  I believe my hub and back plate are both 550K3, but my spindle spacers and chain adjusters are 500K0.  Hence my issue.  My swing arm has a grease nipple, but so do both the swing arm spindles.  I have replaced the plastic swing arm bushes with brass ones and all went together fine.  Thanks again.

Raymond
Raymond

1971 CB500K0 (being rebuilt)
1977 CB550K3 (bases for future 650 cafe racer)
Q plate CB550 in bits

Offline Oddjob

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Re: CB550K3 Rear brake plate spacer
« Reply #9 on: February 10, 2019, 11:40:44 PM »
Grease nipple, plastic bushes, K3 no doubt.
Don't play stupid with me, I'm better at it