Clutch master cylinder for softer pull?

The Brembo RCS' ratio can be adjusted from 18 to 20. This can be a big difference in the pull feel. Don't know if that's enough for you but I find it works. This is the standard RCS, not the more expensive Corsa Conte version. You can see the adjustment there on top of the lever.

Brembo RCS 17 Detail.jpg
 
So on my standard Gen 2 16RCS 16/18 clutch lever is as follows:
On 16 to pull lever to the bar is 3.56kg clutch bites at 13mm released from the bar grip.

On 18 to pull lever to bar is 4.36kg clutch bites at 20mm released from the bar grip.

Fitting the 17RCS 16/18
On 16 to pull lever to grip is 4.68kg clutch bites at 20mm released from bar grip

On 18 to pull lever is 5.36kg clutch bites at 26mm released from bar grip

So there’s not much in it really between 16RCS at 18 or 17RCS at 16.

What I don’t have at this stage is the standard clutch lever info as mine was snapped off when I bought the bike. Does anyone have this info?
 
@CraigMcleod so the 16RCS at 16mm has both the lightest force and the shortest travel? Am I misinterpreting, as I expect the largest force for the shortest travel?

Are these published forces or you measured this somehow?

Thanks for all of the education.
 
@CraigMcleod so the 16RCS at 16mm has both the lightest force and the shortest travel? Am I misinterpreting, as I expect the largest force for the shortest travel?

Are these published forces or you measured this somehow?

Thanks for all of the education.
16RCS set at 16 has the lightest force but ‘longest’ travel to disengage the clutch when changing gear. So if the lever is pulled all the way in as you release only 13mm the clutch starts to bite. Which isn’t much use if you want to give the clutch lever a quick jab coming down the gears as you would have to pull it almost to the grip each time.
The 16 and18mm measurements are a simple cam adjustment on the lever so at 16mm this is 16mm (in theory) from the pivot of the lever. 18mm obviously being 18mm from the pivot point. So when pulling the lever at 16mm it’s easier to pull that if it is at 18mm. the pay off for having a light lever is that you are pushing the master cylinder piston less with 16mm and so pushing less fluid down to the slave cylinder. So you have to pull the lever further in to do the same job as if it was on 18mm. 18mm shifts more fluid but has the leverage effect is less it takes more force to pull the lever.
I measured it myself by using a travel baggage weighing hook on the lever and pulled it back. Then use a calliper to measure distance from bars.
 
@CraigMcleod thank you very much for the explanation and great job with the measurements!

After playing with all those high-end toys you suspect the OEM is the best compromise?
I’ve not actually used an OEM on this bike. If someone can do so measurements that would be great.
My Gen1 has an OEM master cylinder but with a nicer looking adjustable lever.
Just as a comparison it takes 3.5kg to pull lever all the way in and the clutch bites when releasing the lever to 30mm from the grip.
As I understand it the gen2 OEM is a slightly lighter pull than the gen1!

Gen 1 (I think prior to 2003) had a different size slave cylinder to later gen 1’s. The later cylinder was also used in gen 2’s
Now whether swapping slave cylinders would make a difference (they do all fit so are interchangeable) but that could be another can of worms.
Personally I don’t think there is anything to be gained apart from looks to fitting a Brembo clutch lever. Just keep the OEM clutch master cylinder and change the lever for something nicer. They don’t look as good though:cool:

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I’ve not actually used an OEM on this bike. If someone can do so measurements that would be great.
My Gen1 has an OEM master cylinder but with a nicer looking adjustable lever.
Just as a comparison it takes 3.5kg to pull lever all the way in and the clutch bites when releasing the lever to 30mm from the grip.
As I understand it the gen2 OEM is a slightly lighter pull than the gen1!

Gen 1 (I think prior to 2003) had a different size slave cylinder to later gen 1’s. The later cylinder was also used in gen 2’s
Now whether swapping slave cylinders would make a difference (they do all fit so are interchangeable) but that could be another can of worms.
Personally I don’t think there is anything to be gained apart from looks to fitting a Brembo clutch lever. Just keep the OEM clutch master cylinder and change the lever for something nicer. They don’t look as good though:cool:

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Mine has the stock MC and clutch lever with a Brembo brake MC...it kind of looks off balance but I figure if it works and works well......leave it alone...

The sad part of having mis-matched MCs is it is a challenge to change out the levers for something "goochie"
 
Mine has the stock MC and clutch lever with a Brembo brake MC...it kind of looks off balance but I figure if it works and works well......leave it alone...

The sad part of having mis-matched MCs is it is a challenge to change out the levers for something "goochie"
I had a Brembo brake master on my gen 1 and a standard clutch OEM with different lever. I can’t remember the make though, they came from eBay. It looks good and very close match to the Brembo lever. No one ever noticed the difference. It’s been on for years now and still works fine

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I found my standard clutch master cylinder setups on both my Busa Gen 2 and ZX14R were no longer working s standard / effectively once I had fitted heavy duty clutch springs and Brocks clutch kits for both .
So , this is why the RCS16 clutch master was fitted to the Busa , and the RCS17 was fitted to the Kawasaki .
They work pretty well for me , I am used to their take up points , and feel is very good .
 
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