Author Topic: Change o-rings at base of cylinders on CB550K?  (Read 427 times)

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Offline denward17

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Change o-rings at base of cylinders on CB550K?
« on: March 12, 2024, 05:16:43 PM »
1976 CB550K
Is it recommended to change the o-ring that wraps around the oil control valve ?

#40 in picture below.
91310-426-000
O-RING (11X2.5)

The current o-rings appear to be made out of something different than other o-rings, they are still soft and pliable.

The new o-rings that came in the Vesrah kit appear to be same size but made of same material other o-rings are.



« Last Edit: March 12, 2024, 05:18:15 PM by denward17 »

Offline HondaMan

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Re: Change o-rings at base of cylinders on CB550K?
« Reply #1 on: March 12, 2024, 07:38:31 PM »
They don't often leak, but they do get inflexible and seal poorly after disturbing them. I have some: PM me if you need a pair.
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Offline bryanj

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Re: Change o-rings at base of cylinders on CB550K?
« Reply #2 on: March 13, 2024, 01:07:36 AM »
Yes change them but its the ones between block and head that give most problems due to change in head gasket material making them thicker bur suppliers did not increase the size of O ring
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Offline denward17

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Re: Change o-rings at base of cylinders on CB550K?
« Reply #3 on: March 13, 2024, 05:53:43 AM »
Thanks bryanj and Mark, will change them.

I have the 2 for between the head and cylinder from Mark.