I wanted to share my recent experience upgrading my bike’s clutch to 8 plates using the kit from gggGary. A couple of weeks ago, I noticed some clutch slipping during a dyno run, which motivated me to start this project. (this plot is an update from the previousely posted as that one had a slight diffrence in the setup)
Above you can see the clutch giving way at 5500 rpm and then catching again and releasing. The dashed line is the same motor/intake/exhaust setup run last year with no slippage. Here I had the stock configuration 7-plate clutch with EBC fibers and the Vesrah springs, which originally fixed the slipping of my stock clutch, but, I guess, all the dyno runs and 2k miles were too much for it.
I called MMM and he graciously sent me some Ferodo springs (stiffer than Vesrah, but not quite Barnett). Then I figured, while I am here, may as well see about adding another friction plate just to be sure.
The installation process was straightforward. No machining, just a drop in. The result for this 8-plate/Ferodo spring combo: very smooth operation and much improved positive shifting. Almost like a modern bike. Also, the friction zone is much improved and significantly less grabby than the EBC/Vesrah combination I had before. Took it out and ran it up to 7K, so far so good! Will be going on the dyno within a few weeks and will report.
A couple of observations.
The 8 Aldo plates + one steel are heavier than stock 7 friction plates. 690 grams vs 325 grams respectively.
Additionally, the full 8 friction/7 steel plate stack is ~ 1mm thicker than the EBC 7 friction/ 6 steel plate setup
Some of the differences between thickness was due to the Aldo plates varying from 2.5mm to 2.55mm in thickness and the EBC plates were ~ 2.95mm vs 3.0mm stock. In the end, this was not an issue.
With the help of ChatGPT, I ran a quick calculation of whether there would be any of the horsepower eaten up by the greater rotating mass, and the impact, on average, across the rpm range should be negligible
Above you can see the clutch giving way at 5500 rpm and then catching again and releasing. The dashed line is the same motor/intake/exhaust setup run last year with no slippage. Here I had the stock configuration 7-plate clutch with EBC fibers and the Vesrah springs, which originally fixed the slipping of my stock clutch, but, I guess, all the dyno runs and 2k miles were too much for it.
I called MMM and he graciously sent me some Ferodo springs (stiffer than Vesrah, but not quite Barnett). Then I figured, while I am here, may as well see about adding another friction plate just to be sure.
The installation process was straightforward. No machining, just a drop in. The result for this 8-plate/Ferodo spring combo: very smooth operation and much improved positive shifting. Almost like a modern bike. Also, the friction zone is much improved and significantly less grabby than the EBC/Vesrah combination I had before. Took it out and ran it up to 7K, so far so good! Will be going on the dyno within a few weeks and will report.
A couple of observations.
The 8 Aldo plates + one steel are heavier than stock 7 friction plates. 690 grams vs 325 grams respectively.
Additionally, the full 8 friction/7 steel plate stack is ~ 1mm thicker than the EBC 7 friction/ 6 steel plate setup
Some of the differences between thickness was due to the Aldo plates varying from 2.5mm to 2.55mm in thickness and the EBC plates were ~ 2.95mm vs 3.0mm stock. In the end, this was not an issue.
With the help of ChatGPT, I ran a quick calculation of whether there would be any of the horsepower eaten up by the greater rotating mass, and the impact, on average, across the rpm range should be negligible
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