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Re:Barnett question (clutch)
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TOPIC: Re:Barnett question (clutch)
#1028906
ctkog (User)
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Re:Barnett question (clutch) 2 Weeks ago  
G_Conway wrote:
I understand the bearing design just fine. My main issue is lack of detailed understanding of the operation of our clutch.

I am assuming that the apply plate is never freewheeling. For vibration and flywheel effects alone, I am assuming there has to be a load on the bearing at all times (just changes from lighter load in clutch release and heavy load in apply, or vice versa if my understanding is wrong.) Like I said, I do not really have good understanding of the mechanics of the design.


True, the pressure plate is never freewheeling. It's attached to the hub that goes into the tranny. The hub section can be at rest (in neutral or with that clutch pulled at a stop), engaged or in the process of engaging the clutch basket (which is geared to the engine and always spinning). When engaging the clutch the pressure plate begins engaging to pair the hub with the clutch basket speed by friction. Once they're spinning at the same speed the clutch is fully engaged.

This may help with getting a clear understanding of how the clutch operations works. https://www.youtube.com/watch?v=agLa0A8GAfc

Only time there is pressure on the throw out bearing is when you pull in the clutch cable to shift. Between shifts (clutch engaged) there should be no load on the bearing unless the cable is not adjusted correctly with end freeplay.

I agree with Ron that for a few extra bucks it's worth upgrading the barnett bearing before installing it. That bearing barnett puts in there is not designed for side loads. Most all the load goes right on contacting the one side of the bearing race ridge.
 
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Last Edit: 2018/02/11 02:07 By ctkog.
 

---------- NOTHING STRAIGHTENS MY HEAD OUT BETTER THAN AN ENTIRELY CROOKED ROAD-----------
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#1028907
davej (User)
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Re:Barnett question (clutch) 2 Weeks ago  
My guess that any issues with the bearing on the Barrnett setup was from lack of proper adjustment/or installation and the bearings that failed were always in contact and spinning. Just my thoughts.
 
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#1028909
BikerRon (User)
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Re:Barnett question (clutch) 2 Weeks ago  
Personally, the way I ride, doubt if I’ll ever need to replace my clutch, but if I did throw in a Barrett clutch there’d be an extra 12 bucks spent on a better bearing design that would be on the list.

 
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Last Edit: 2018/02/10 11:53 By BikerRon.
 


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#1028910
ctkog (User)
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Re:Barnett question (clutch) 2 Weeks ago  
The way I ride it's no wonder my ebc slips
 
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#1028911
BikerRon (User)
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Re:Barnett question (clutch) 2 Weeks ago  
Lol
 
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#1028913
ctkog (User)
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Re:Barnett question (clutch) 2 Weeks ago  
Just for the hell of it until I can get a barnett in the spring I have two stock springs I'm going to have the guys at work tack them together.

I'll let y'all know how it works out.... or doesn't.. more likely. haha
 
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#1028917
roadiemort (User)
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Re:Barnett question (clutch) 2 Weeks ago  
ctkog wrote:
Just for the hell of it until I can get a barnett in the spring I have two stock springs I'm going to have the guys at work tack them together.

I'll let y'all know how it works out.... or doesn't.. more likely. haha
No need to tack them together, some have run doubled up diaphragm springs for years many years ago.
 
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#1028919
ctkog (User)
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Re:Barnett question (clutch) 1 Week, 6 Days ago  
Thanks Roadiemort!

... and that image really stretches the point.
 
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#1028926
G_Conway (User)
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Re:Barnett question (clutch) 1 Week, 6 Days ago  
Well, I got my stock clutch kit (Yamaha 4WM-W001G-00) and my Barnett spring conversion set.

In talking with Barnett, I decided to go with the standard Barnett springs, as that is what they recommended for a non-race cruiser.
I also asked them about the bearing issue. Their reply wast that they "have had a few, but they were all high mileage bikes." This was by email so I did not get to clarify if the meant the Barnett had high miles on it, or just the bike.

After watching a few videos on our specific clutch, I feel I now have a much better understanding as to the bearing.

It becomes easy to see how improper clutch cable settings could be very detrimental to the bearing. Too loose, and the pull will start to angle which will put uneven pressure on the bearing causing it to spin constantly (under an uneven load.) Too tight and the bearing will be under a constant side load which will cause wear much quicker.
I can see where the angular bearing "could" potentially be better, but there were other questions / issues that concern me as to the use of the angular bearing.
1. The Specs on the angular state a max RPM of 20K. If the pull and cable are adjusted properly, and the bearing and plate are not angled in any way, that shouldn't be a problem. My concern would be that any misalignment of the plate or bearing could push the bearings RPM near or up to the max. In general, mechanical designers then to spec components such that they are expected to see no more that 60-70 percent max load under peak performance. The angular is nowhere near that.

2. Since the Yamaha is listed only under a Yamaha part number, I can't find and specs on the bearing, so it could be 100% stronger (or weaker.)

Since Barnett said the bearing they use IS the same one from Yamaha (I didn't understand if they buy them from Yamaha, or they know the "aftermarket" part number) and the stock Barnett springs are only 20-25% STRONGER than the Yamaha spring plate, I'm going to stick with the standard bearing. I think if I was going to do the HD springs, I would give more serious thought to the angular bearing.
 
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Gerry
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#1028928
roadiemort (User)
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Re:Barnett question (clutch) 1 Week, 6 Days ago  
Anxiety interrupts the brain’s capacity to ignore these distractions by numbing a group of neurons in the pre-frontal cortex that are specifically involved in making choices. Glad you got it sorted.
 
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