The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: skippyc on August 11, 2016, 04:05:01 AM
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I have just replaced the boot on the clutch actuating arm and what a pain it was. Question. Is the spring that goes under the boot meant to be so strong and long to make it so hard to get the arm back on?
The spring is about 1.5" long. Bike is a 1986 model.
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I have an external spring so a different arrangement but it's typical of a German manufacturer to make the spring stronger than it needs to be.
What I did was to measure the clutch pull at the handle bar lever using a spring balance, with and without the return spring. Without the spring the pressure needed to pull the clutch reduced dramatically. I forget the exact figure now but the spring was responsible for something like 40% of the effort. I reasoned that a lighter spring would function Ok as all it has to do is push the arm and cable back to relieve pressure on the thrust bearing. What I got in return was a noticeable lighter clutch pull.
Your experience may differ but it's something to think about.
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I had the same thoughts as you Barry about looking for a lighter spring. It is such overkill, that I wasn't sure it was the right spring fitted.
I suspect that someone has removed the anchor bolt without releasing the clamp and the spring has ripped the rubber boot.
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That spring pushes the rubber boot up against the clutch lever to make sure it seals against water intrusion .
It also puts a small load on the clutch arm to take up the free play from the cable adjustment, there is a small gap between the clutch pushrod and clutch arm adjustment bolt when the cable is adjusted correctly .
When removing the clutch arm at the transmission, make sure the clamp that secures the boot on the transmission case is loose, or removed and that the boot is pulled free from the case, the spring will put enough force on the boot to tear it when the pivot bolt for the clutch arm is removed, if the boot is old and hardened with age .
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And the post 1981 edition is double the price of the earlier one.