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Discussion Starter · #1 ·
I have an Oberon slave cylinder. Still trying to diagnose a leak. I noticed that the push rod spins if I grab it. Should it? I assume it should not and probably burned the inside of the slave. Anyone have a part number for the bearing and where it is? Thanks.
 

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Yes it can spin when the slave is off. There are tabs or pins that will slide into your slave cyl. to keep it from spinning during operation.
 

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It won't. Think of it this way:

The push rod goes through the lay shaft and into the clutch basket, through the clutch pack and into a "hat" that goes into the bearing in the pressure plate.

The bearing is there so that the clutch, with all of its components is free to spin while leaving the push rod stationary.

So, if the engine is not running, and you grab the push rod, you absolutely should be able to spin it. That tells you the bearing is not seized.

If the bearing seized, it would turn the push rod, at what ever engine RPM while your slave cylinder was pressed against it.

If you were to attempt to rotate the push rod with a seized bearing, it would be difficult to rotate if not impossible.

The "hat" that keeps the push rod from going all the way through the bearing has a nitrile o-ring inside it.

It gets all gummed up in there with the clutch dust and old grease so the push rod would have to turn within that, if the bearing was seized.
 

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In neutral with engine running if you don't touch the clutch lever it's normal the rod turn because of bearing drag. But if you pull lever in the rod should not spin. As said before with slave removed (engine off) you should be able to spin rod by hand, if you're not the pressure plate bearing need to be replaced.
 

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With the 848 bikes they came up with a t-slot on the pushrod. No idea if this will work with your bike though.

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Discussion Starter · #7 ·
Great info. So I started the bike without the slave in and see that the push rod rotates was the bike runs. So what everyone is saying is that is normal but when the clutch is pushed in it grabs the rod and stops it? To me of the push rod is spinning in the slave it would ruin the seals in there from the rotation. Am I missing something? If your push rod had the pin it would be anti rotation and would not spin at all in the slave.
 

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Check the rod for wear. Check the slave for wear. Check the bearing in the pressure plate.
Too little clearance between actuating rod and pressure plate will cause rod to spin.
Correct clearance is a result of clutch stack height. Check stack height.
 

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Discussion Starter · #9 ·
The problem is I am reading mixed information. Some say the rod is supposed to spin while other say it is not. If I can spin it by hand, then as stated above the bearing is not seized, but it is moving with the engine on in neutral with the slave off.
Something is causing my leak. Seals replaced. Bearing not seized. Oberon slave bad?
don’t mean to be dense here, but what am I missing?
 

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The problem is I am reading mixed information. Some say the rod is supposed to spin while other say it is not. If I can spin it by hand, then as stated above the bearing is not seized, but it is moving with the engine on in neutral with the slave off.
Something is causing my leak. Seals replaced. Bearing not seized. Oberon slave bad?
don’t mean to be dense here, but what am I missing?
Theoretically the rod should not spin and only move side to side to allow the slave to push the pressure plate away from the clutch. The earlier design had nothing to stop the rod from spinning, only the bearing in the pressure plate isolates the rod from the spinning of the plate. This solution is not 100% effective especially when the bearing starts to go. Later designs had the cross pins to stop the rod from spinning.

the rod has o-rings which can wear and leak. Worn bearings will cause spinning of the rod which will accelerate wear of the o-rings
 
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