OP
OP
OK, I finally pushed the clutch M/C replacement project over the finish line. Success, I think. I achieved my goal of lower pull force. I don't notice that the engagement zone is too much wider, but it is indeed closer to the handlebar. The lever feels a bit mushy on top vs. hard as a rock (ie:'"wooden") with the original. It does engage and disengage completely, so it works fine. (See UPDATE below) There is no crawl with the clutch in; no clunky shifting; and no slipping on hard acceleration. It is similar in effect to installing a smaller diameter brake M/C.
Giving the 2007 VFR800 1/2" diameter master cylinder a vibratory bath in Extreme Simple Green aircraft and precision parts cleaner...
The cleaned master cylinder along with the parts from the TourMax rebuild kit...
Installed and bled. It took a lot of draw-through with my vacuum bleeder to get the air out...
Buttoned up for a test ride...
I'm going to call it a success, as it functions properly and met my goal of reduced lever effort.I wish it engaged higher from the bar and that the first bit of travel didn't feel limp, but I think it is a keeper because of my arthritic wrist and hands. UPDATE: The limp travel at the top was determined to be because of a worn lever pivot. I replaced the lever and pivot assembly with new OEM parts and this issue is completely resolved.
I'll continue to evaluate it before doing likewise with the brake master cylinder. UPDATE: The brake cylinder was also replaced. See here...
https://www.st-owners.com/forums/threads/brake-master-cylinder-swap.168536/#post-2156310
If I get one from the same VFR donor, the two will again match being both silver instead of black. Not all VFR800 M/C's are half-inch bore. That is an important spec to meet. I had considered doing a Brembo aftermarket cylinder. It would have given me the choices of 12mm or 13mm. With half inch = 12.7mm, I think that 13mm would be the better of the two choices. A 12mm cylinder might be pushing the concept a bit too far.
Giving the 2007 VFR800 1/2" diameter master cylinder a vibratory bath in Extreme Simple Green aircraft and precision parts cleaner...
The cleaned master cylinder along with the parts from the TourMax rebuild kit...
Installed and bled. It took a lot of draw-through with my vacuum bleeder to get the air out...
Buttoned up for a test ride...
I'm going to call it a success, as it functions properly and met my goal of reduced lever effort.
https://www.st-owners.com/forums/threads/brake-master-cylinder-swap.168536/#post-2156310
If I get one from the same VFR donor, the two will again match being both silver instead of black. Not all VFR800 M/C's are half-inch bore. That is an important spec to meet. I had considered doing a Brembo aftermarket cylinder. It would have given me the choices of 12mm or 13mm. With half inch = 12.7mm, I think that 13mm would be the better of the two choices. A 12mm cylinder might be pushing the concept a bit too far.
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