Author Topic: O rings  (Read 658 times)

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Offline beemerbum

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O rings
« on: October 20, 2017, 02:25:26 PM »
Could someone please tell me the correct size of the O rings used in attaching lines from the oil tank to the engine on a CB 750?

Offline CycleRanger

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Re: O rings
« Reply #1 on: October 20, 2017, 02:38:20 PM »
Looks like 15x2.5 at the engine.

Do you have a copy of the parts list? :)
http://www.honda4fun.com/materiale-documentazione-tecnica/parts-list/parts-list-cb750
Do you have a copy of the Honda Shop Manual or Parts List for your bike? Get one here:
https://www.honda4fun.com/materiale/documentazione-tecnica
CB750K5        '79 XL250s     CL350K3
CB750K3        '76 XS650      '76 CJ360T

Offline ekpent

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Re: O rings
« Reply #2 on: October 20, 2017, 02:42:07 PM »
 You can buy a bag of 15 x 2.5 on E-bay in Viton pretty cheap. They also fit between the oil pump and crankcase if you ever dig in that deep and want fresh ones.  Think its the same size on the oil filter bolt as well .
« Last Edit: October 20, 2017, 04:20:21 PM by ekpent »

Offline beemerbum

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Re: O rings
« Reply #3 on: October 20, 2017, 02:43:03 PM »
I do now. Thank you

Offline CrankyOldGuy

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Re: O rings
« Reply #4 on: October 20, 2017, 02:58:51 PM »
Transmission repair shops usually carry a large range of 0-rings ... the shop next to our office will also make ones to order.
750 K1 Original Owner

Offline PeWe

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Re: O rings
« Reply #5 on: October 21, 2017, 12:30:42 AM »
Here a chart of CB750 O-rings I have found on this forum.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline beemerbum

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Re: O rings
« Reply #6 on: October 21, 2017, 07:32:22 AM »
Here a chart of CB750 O-rings I have found on this forum.
Thank you. I cannot imagine working on these old bikes without the knowledge on this forum