2002 Monster S4 Clutch Master Rebuild kit

[2 Wheel Wanderer]

I need to rebuild my clutch master. The bike starts to move forward when pulling the lever and holding it after 10-15 seconds. I am looking at this rebuild kit but am not sure if it will work. I'd rather not spend $250+ for a new one if I dont have to.

https://www.gothamcycles.com/Clutch/ducati-brembo-12mm-front-brake--clutch-master-cylinder-rem-rec-seal-rebuild-kit.html

Wondering if anyone here will know. Below is a picture of the bottom of the master cylinder. Thank you!

[ducpainter]

Are you sure it's the master, and not the slave?

[2 Wheel Wanderer]

Are you sure it's the master, and not the slave?

Yeah, already replaced the slave with an Oberon. It's a good upgrade even though it wasn't the problem.

[ducpainter]

I'm seeing conflicting info online as to whether that kit will work on a remote reservoir type master.

I'm thinking this might be the one you need, assuming you have a solid pivot master... https://store.bevelheaven.com/Brake-Related-Parts/Brembo-12mm-M%7CC-Rebuild-Kit-SOLID-PIVOT-type/

[koko64]

Any evidence of fluid loss or leakage around the master cylinder piston? Check the rubber boot at the lever for moisture.

I had an Oberon slave cylinder fail in a few months, so double check for leaks there too just in case you were unlucky.

[stopintime]

Nate's suggestion seems to be for a vintage type master (?) judging from the pictures in the listing. Send your picture to Gotham and Bevel heaven and ask?

[2 Wheel Wanderer]

No fluid loss or leakage around the master cylinder piston and the slave is good. I think ducpainter's link to Bevel Heaven could be the right one. Hopefully. I do have a solid pivot. I sent them a message. Gotham said theirs doesent work and there isnt any rebuild kits that work for me. The pistons in both rebuild kits are different so we'll see what Bevel Heaven says. Thank's for all the responses so far. I'll respond with what Bevel Heaven says.

[2 Wheel Wanderer]

From Bevel Heaven- brembo doesnt sell ANY rebuild kits for any size master cylinder that type that you have.

He does sell 13mm master cylinders that look just like the one I have so I'll probably be ordering that.

Thanks for the help guys.

[stopintime]

I remember some issues with old bikes clutch push rods getting stuck in the pressure plate, spinning on the slave piston, heating it until bad things happened... Later they were made with a pin through them, held in place in the slave, to prevent them from spinning  No idea if that's relevant.

[Howie]

I remember some issues with old bikes clutch push rods getting stuck in the pressure plate, spinning on the slave piston, heating it until bad things happened... Later they were made with a pin through them, held in place in the slave, to prevent them from spinning  No idea if that's relevant.

Your memory is correct.  The symptoms of that are clutch engagement sticking and failure to disengage.

Finding rebuild kits for non vintage Brembo parts is very difficult.  I couldn't confirm it, but I believe you bike came with a 13mm master.  A post on Ducacims agrees with me, but that far from proves it. Are you the original owner@  Sounds like you have the master apart.  What shape is the bore in?  If not close to perfect the cylinder is not rebuidable.

I did find this.  https://www.oppracing.com/product_display/30820-brembo-oe-master-cylinder-clutch-ps-13x25-without-reservoir-w-polished-adj-lever-57-axial-front-gold-10974023/  It is not listed for your bike, but I think is the correct one.  Give them a call.

[Duck-Stew]

I did see some pushrods get stuck, and spin until it machined itself to a shorter dimension.

Just fyi.