Something I haven't read about yet. Clutch issues...

[Doc Brown]

Of course I have read about clutch issues, especially about dragging issues and after one of my Gassers did it so vigorously that I had to sell it I thought I am done with all thousand things I tried.

But, after reading in a British forum that someone altered his clutch master cylinder and was able to increase bore size I have an idea I'd like to try. Especially because my low hour 2019 EC 300 started to get the dragging issue when engine is hot. First appeared after about 20 hours and when ambient temps were in the 90's.

My system is perfectly bled, I change gear oil exactly every 20 hours or earlier using Bel Ray Gearsaver 80 as this reduced clutch squeal quite a bit.

However, all the ideas of longer clutch rod and washers underneath the throwout bearing etc. can not work as a longer rod or a thicker washer will not alter the lift on the pressure plate.

But a bigger master cylinder, pushing the slaves piston further out would. Hence I am interested if there is a bigger Magura master than the standard one (9.5 mm diameter). Maybe one from a different brand like KTM or Sherco. While I know the diameter of the GG master I have no clue what bigger diameters would be available from Magura. Convert to a brake oil based system is possible too but I do not know if there is a different slave that would fit...

I'd appreciate your thoughts...

 

[gasgasman]

A trick back in the day was to use a valve adjusting shim to add length to the clutch push rod.

On the clutch master cylinder. You will need a longer stroke to increase the slave cylinder stroke.

 

[Doc Brown]

Adding shims or even using a longer rod (I tried three different lenght on my former bike) will not change anything. The shim or rod will just push the slave piston back in its housing. It won't add lift.

I talked to a German dealer and he said he has brake fluid resistant o-rings for the slave. So I could change the Magura for a 10 or 10.5 mm Brembo clutch master. I am hesitating because I fear that the clutch pull will be even harder.

 

[Anders]

Adding shims or even using a longer rod (I tried three different lenght on my former bike) will not change anything. The shim or rod will just push the slave piston back in its housing. It won't add lift.

I talked to a German dealer and he said he has brake fluid resistant o-rings for the slave. So I could change the Magura for a 10 or 10.5 mm Brembo clutch master. I am hesitating because I fear that the clutch pull will be even harder.

There are also Magura 10.5mm masters available, e.g part number 2700185

 

[Doc Brown]

There are also Magura 10.5mm masters available, e.g part number 2700185

Cool!

Thanks mate

 

[gasgasman]

Adding shims or even using a longer rod (I tried three different lenght on my former bike) will not change anything. The shim or rod will just push the slave piston back in its housing. It won't add lift.

You can't compress a liquid.
The motion applied at the master cylinder, will transfer to the slave cylinder.
Your master cylinder maybe bleeding off internally.

 

[Jakobi]

You can't compress a liquid.
The motion applied at the master cylinder, will transfer to the slave cylinder.
Your master cylinder maybe bleeding off internally.

I think Doc means like when you throw fresh brake pads in.

The difference is offset by the fluid level rising in the master. The change at the pedal or lever remains the same.

 

[Doc Brown]

You can't compress a liquid.
The motion applied at the master cylinder, will transfer to the slave cylinder.
Your master cylinder maybe bleeding off internally.

You can take off the slave cylinder and push the piston back in its housing easily and that is exactly what happens when you install a shim or a longer rod and that is why this trick never has worked and never will.

 

[Gasser Nate]

My 2018 is oil based. Is yours not?

 

[Doc Brown]

If you ask me, mine is oil based. I don't get what's behind the question to be honest

 

[Gasser Nate]

Adding shims or even using a longer rod (I tried three different lenght on my former bike) will not change anything. The shim or rod will just push the slave piston back in its housing. It won't add lift.

I talked to a German dealer and he said he has brake fluid resistant o-rings for the slave. So I could change the Magura for a 10 or 10.5 mm Brembo clutch master. I am hesitating because I fear that the clutch pull will be even harder.

This is why is asked, you mentioned brake fluid resistant o rings...

 

[Doc Brown]

This is why is asked, you mentioned brake fluid resistant o rings...

Yes, but in context with a Brembo master. Brembo master cylinders are available in various sizes but only for use with DOT brake fluid. So some guys replace the OEM o-rings with brake fluid resistant o-rings and use a Brembo master instead of the Magura.