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JeffTue Jan-03-06 04:03 PM

  
"750 Clutch"


  

          

Greetings, while studying the manuals (to replace the front sprocket) it looks like I have to remove the alternator, clutch & primary chain, and reomove the primary case to R&R the sprocket.

I would like to fix my clutch, which still seems heavy (after replacing the clutch cable and fitting 750 Atlas clutch actuating lever). I am planning to use a Norvil clutch rod seal, replace clutch plates, inspect the clutch drum and pressure plate.

So I have two questions:
1) should I convert the 750 four plate clutch to the five plate (850) clutch arrangement? My understanding, would require 850 pressure plate or machine work on my 750 pressure plate

2) what are the benefits/disadvantages of the Sintered Bronze (Norvil style) clutch plates vs. the Barnett clutch plates available here in the US

thanks, Jeff

  

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dynodaveyWed Jan-04-06 07:28 AM

  
#1. "RE: 750 Clutch"
In response to Reply # 0


  

          

Hi Jeff
You will have better luck by understanding the nature of your clutch, rather than just changing parts.
If you measure the components and compare them to my data you can then decide what to do. What are the measurements?
Here is my data for a comparison.
http://atlanticgreen.com/clutchpak.htm
You can see there is negligable difference in stack height between the thick and thin PP clutch. Therefore the type of clutch has virtually NO effect of pull effort.
It is entirely due to the stack height and then....all other external components.
Here is a run down on the effect of clutch stack height.
http://atlanticgreen.com/ndnsclutch.htm

non-stock components and other methods are available to tune this overall thickness, which DIRECTLY affects the pull effort.

Are you outside the US or Canada?
dynodave
http://atlanticgreen.com/
-over 1400 CRS since 1989
-FWIW supplier of clutch rod seals to Norvil

  

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JeffWed Jan-04-06 11:02 AM

  
#2. "RE: 750 Clutch"
In response to Reply # 1


  

          

Greetings, so:
clutch plates 4 Barnett #524-S 4 x .080 = .32
friction plates 5 Barnett #524-73 5 x .125 = .625
late thin pressure plate 06-3768 1 x .227 = .227
---
stack height = 1.172

Do you have the Barnett clutch plates? I had a Barnett
clutch on another make bike, years ago. They warned
me about the clutch locking up(but I never had any trouble)

re: clutch rod seal, it would be better to order
within the USA to avoid shipping & duties. Thanks, Jeff

  

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dynodaveyWed Jan-04-06 12:16 PM

  
#3. "RE: 750 Clutch"
In response to Reply # 2


  

          

From the quantities and numbers you have measured, you already have a thin PP clutch(850)....
If you substitute an early friction plate you will increase your clutch stack height by .020/each and reduce the release pressure (as well as the griping power).
Yet with a stock thickness clutch and an atlas clutch release arm, with proper cable routing of a lubed cable I'm surprised you can't release it with one finger alone?

One of my clutches is .050" thicker than stock and with the atlas lever I can pull the clutch lever with my pinkie finger ...

Have you actually tried this setup and find it doesn't work easily enough for you?

  

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