Author Topic: Which ring goes on top - CB750- deja vu all over again?  (Read 1632 times)

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Offline Magpie

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Which ring goes on top - CB750- deja vu all over again?
« on: August 15, 2011, 05:42:45 PM »
I did a search found the thread and got confused, again. The 3 lower rings are easy to spot, I know marked side up, but the other 2 rings are: one is dark grey with silver edge and has a "stepped" top edge and the other is darker in colour with both edges being sharp and well defined. These are Riken rings. Here's some pics to help. Thanks in advance!

Offline MCRider

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #1 on: August 15, 2011, 05:51:57 PM »
The silver edged ring is a hardened chrome (I think) which helps you remember its for holding back the combustion hence its the top ring. The black ring is of a lesser material and does a lesser job, that of scraping the oil back down the cylinder wall. Hence its name scraper and its second position, directly above the oilring which releases the oil the scraper scrapes.

I have some Yoshimura 2 ring slipper pistons which simply did away with the scraper altogether. Too much friction.  :)
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Offline Magpie

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #2 on: August 15, 2011, 07:25:57 PM »
Thanks MCRider! Cliff.

Offline marcuch

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #3 on: December 18, 2012, 02:25:58 PM »
Magpie, how did you determine what side was up on your Riken rings?  The "chrome" ring has a "R" stamped on one side so I assume that side is up.  But the "Dark" ring has no markings that I can see.  Since it looks the same on each side does it matter?  Thanks folks
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Offline Xnavylfr

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #4 on: December 19, 2012, 03:30:29 PM »
If you look at the cross section of the ring , you will notice that the sides are NOT 90 degree to the top surface. rings are installed with the taper DOWN...



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Offline crazypj

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #5 on: December 19, 2012, 03:36:14 PM »
Pretty sure most genuine Honda manuals have a cross section drawing showing correct orientation.
second scraper has to scrape, if there is a cutaway, it goes down which will put taper in correct position (think pyramid)
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Offline marcuch

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #6 on: December 19, 2012, 08:55:53 PM »
Makes sense... I also found a diagram that clears things up.
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Offline 70CB750

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #7 on: December 20, 2012, 04:18:04 AM »
So the top ring is symetrical and can go either way?
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Offline Xnavylfr

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #8 on: December 20, 2012, 05:10:04 AM »
According to the diagram I'd say yes, but the TOP ring is always marked in some way. I guess so people know it's the TOP ring!!!


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Offline markb

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #9 on: December 20, 2012, 08:07:18 AM »
I also found a diagram that clears things up.
Yes it does.  Thanks for that post.   :)
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Offline crazypj

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #10 on: December 20, 2012, 06:04:04 PM »
Pretty amazing the things you find in genuine manual  ;)
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Offline Gregorymoto

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Re: Which ring goes on top - CB750- deja vu all over again?
« Reply #11 on: December 23, 2012, 06:02:16 AM »
:)
Yep, i have issues with this sort of stuff.