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Discussion Starter · #1 ·
I have removed the clutch push rod from the transmission and inserted the outboard end into the slave cylinder receiver (thrust bearing?) to check the fit. There is a fair bit of side to side and end play between the inner race and bearings of the thrust bearing. Not having this apart, I am not sure I am describing this properly, but I am sure the play is not from the fit of the clutch push rod and the 'receiver' it fits in on the clutch slave cylinder. Is some wear normal here or am I into signs of a thrust bearing failure and replacement of the slave cylinder? The bike has about 30,000 miles on it.
 

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2005 K1200LT
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I would go with a new slave. Mine was apart at the dealer at less than 20K (for rear tranny under warranty) and just told them to install an new slave. The bearing is always under load (push the rod all the way in against the spring and that is the clutch engaged load). Then see how much it wiggles.
 

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At 30k just go ahead and replace the Slave for sure. No way I would put it back in at that mileage.
 

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Slave

cccpastorjack said:
At 30k just go ahead and replace the Slave for sure. No way I would put it back in at that mileage.
I politely differ. Last time I saw my old '99 LT, it had 240k and was still running the original slave cylinder. So if there is something wrong with it, ya. Otherwise no.
 

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The pushrod is not a tight fit in the bore of the bearing. Quite a bit of clearance. The bearing is a ball thrust bearing, and the race also has a little side to side movement, as the balls are between to "plates" to take thrust, not radial loads.

I say that if you have one out at 30,000 miles, replace it no matter how good it looks. A LOT of them have failed in the 20-50,000 mile range, you would really kick yourself if you put it back in and it failed in the next 10K miles, now wouldn't you? I know I would. It is not so expensive to try and stretch it's use to the bitter end.
 

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HarvRead said:
I politely differ. Last time I saw my old '99 LT, it had 240k and was still running the original slave cylinder. So if there is something wrong with it, ya. Otherwise no.
ONE slave cylinder that made it to high mileage is not statistics! ;)

I think the odds are against many of them making it past 50-75K miles. Many have failed way before that.
 

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Discussion Starter · #7 ·
Thanks for all the good information. My wife and I are planning to pick up our aborted (last year) trip across Canada this summer and it is probably best to not take the chance. I live in a part of Canada where you can't easily get parts. But, I do have the winter lay-up so I have ordered the parts and will do the replace before reassembly. I guess I just needed someone to hit me with a plank to get my attention. Thanks again to all who responded.
 

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Discussion Starter · #8 ·
Calling David Shealey!!

I have received the new slave cylinder from a US supplier. Delivery not too bad, ordered on 02/01 and received 02/07. Cost of 136.00 total including shipping. Not too shabby! As a point of interest, cost here would have been 212.00 plus 14% taxes and I would have to travel 500 mi. round trip or pay additional for shipping.

Enough about that! Getting to the real purpose of this thread before I make the new install, I have a question and then an observation. Does the clutch push rod and thrust bearing rotate at engine speed at all times but come under full load only when the clutch is engaged? I also noticed the new cylinder has lubricant inside the hole where the push rod engages, there is none on the vertical face of the inner race where the squared shoulder of the push rod makes contact.

Another question, on the inboard clutch end of the push rod there is a tapered shoulder about 1 1/4" from that end. From the brownish look of that shoulder it looks like that is the contact point for the push rod and the clutch plate. Is that the case? and; Would it help to apply lubricant (suggest the Locktite Moly lube) on either or both the tapered and square shoulder?
 

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I am not David but

I am not sure about your first question but I think that if the pushrod is in contact with the slave it will rotate the bearing.

ajs said:
Another question, on the inboard clutch end of the push rod there is a tapered shoulder about 1 1/4" from that end. From the brownish look of that shoulder it looks like that is the contact point for the push rod and the clutch plate. Is that the case? and; Would it help to apply lubricant (suggest the Locktite Moly lube) on either or both the tapered and square shoulder?
This one I am sure about. The inboard shoulder presses on to the diaphgram spring plate - it is inside the clutch housing and if any grease gets flung of it can only land on or near the clutch plate. I am not sure if you could apply enough grease that would stay on to be effective. I would not grease.

Regards from near the original Glasgow
 

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Discussion Starter · #10 ·
Regards from near the original Glasgow[/QUOTE]

Thanks for the response Grahamw, I think that's why we call this one NEW Glasgow.
 

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ajs said:
Calling David Shealey!!

I have received the new slave cylinder from a US supplier. Delivery not too bad, ordered on 02/01 and received 02/07. Cost of 136.00 total including shipping. Not too shabby! As a point of interest, cost here would have been 212.00 plus 14% taxes and I would have to travel 500 mi. round trip or pay additional for shipping.

Enough about that! Getting to the real purpose of this thread before I make the new install, I have a question and then an observation. Does the clutch push rod and thrust bearing rotate at engine speed at all times but come under full load only when the clutch is engaged? I also noticed the new cylinder has lubricant inside the hole where the push rod engages, there is none on the vertical face of the inner race where the squared shoulder of the push rod makes contact.
That is correct. What you are looking at in the end of the slave cylinder piston is the thrust bearing, and it is greased at the factory. That spins all the time the engine is running, just as you suspected. It is just the spring load of the spring in the slave cylinder keeping it snugged up on the rod, with full pressure put on it when you press the clutch handle in.
Another question, on the inboard clutch end of the push rod there is a tapered shoulder about 1 1/4" from that end. From the brownish look of that shoulder it looks like that is the contact point for the push rod and the clutch plate. Is that the case? and; Would it help to apply lubricant (suggest the Locktite Moly lube) on either or both the tapered and square shoulder?
It does not hurt to put a VERY small amount of lube on the tapered shoulder on the front end of the rod, and as you correctly figured out again, that presses in the center of the diaphragm spring to release the clutch. It does not spin against that surface, just pushes on it.
 
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