Clutch master cylinder anodising flaking in the bore.

G

Gibbo

Joined Jul 2017

30 Posts | 15+

Cairns , Australia

Discussion Starter
• Jul 19, 2019

• #1

Hi Guys,
Well i discovered that the strange things my clutch was doing is because the master cylinder bore has some of the anodising flaking off. This is allowing fluid to leak past the piston as well as wearing out the piston seal.
Short of replacing the whole clutch master has anyone had a fix for this?
My 1st attempt is i'm going to hone out the cylinder but an internet search hasnt found anyone who has tried this.

 

Rainerio

Joined Jun 2013

1K Posts | 268+

San Francisco CA. USA

• Jul 20, 2019

• #2

What kind of brake fluid were You using?

 

G

Gibbo

Joined Jul 2017

30 Posts | 15+

Cairns , Australia

Discussion Starter
• Jul 20, 2019

• #3

Its a magura mineral oil clutch.
I dont know what the previous owner used but i used Motorex mineral oil

 

J

Junkie

Joined Jun 2019

105 Posts | 14+

Alameda, CA

• Jul 20, 2019

• #4

the clutch masters on these bikes are a common point of failure. I'd recommend swapping it for an aftermarket unit.

 

Taffy

Joined Nov 2001

17K Posts | 773+

Ely, England

• Jul 21, 2019

• #5

100598 in my web shop mate. I'd sell you a litre of mineral oil for the same as your 100cc but 1KG of mineral oil posted would cost more than the saving.

if you think it has had other than mineral oil in there get the anti-slosh rubber as well as they dissolve in brake fluid. and again, there's two M/C repair kits
brake piston
clutch piston

two anti-slosh cvups
brake
clutch

always get a piston slave O ring and always bleed with a syringe.

there's also a gaitor repair kit to tidy that up too.

cheers

Taffy

 

G

Gibbo

Joined Jul 2017

30 Posts | 15+

Cairns , Australia

Discussion Starter
• Jul 21, 2019

• #6

Junkie said:

the clutch masters on these bikes are a common point of failure. I'd recommend swapping it for an aftermarket unit.

Click to expand...

Who does an aftermarket master cylinder?
Ive seen slave but not the master

 

J

Junkie

Joined Jun 2019

105 Posts | 14+

Alameda, CA

• Jul 21, 2019

• #7

Oops, sorry, was tired. You're correct that it's the slave that often fails.

Brembo does a clutch master RCS but it uses an external reservoir so it's awfully bulky, Beringer does one too but $$$$$. Not sure if either can use mineral oil.

 

Taffy

Joined Nov 2001

17K Posts | 773+

Ely, England

• Jul 22, 2019

• #8

cheapest i can do is 220gbp. about $275 US. $390 australian.

they don't make the 163 model anymore, it is now called the 167 model.

Taffy

 

• 

Reactions: 1 person

G

Gibbo

Joined Jul 2017

30 Posts | 15+

Cairns , Australia

Discussion Starter
• Jul 22, 2019

• #9

No worries Taffy
The aussie dollar isnt real healthy at the moment sadly.

 

Taffy

Joined Nov 2001

17K Posts | 773+

Ely, England

• Jul 22, 2019

• #10

there is one called a "Hebo" ....not sure how good it is. sounds like a used one should do you though! I can do a used one for $240 AUS.

Taffy

 

G

Gibbo

Joined Jul 2017

30 Posts | 15+

Cairns , Australia

Discussion Starter
• Aug 5, 2019

• #11

Well i just got back after 2 weeks away with work without a lot of mobile phone reception and had a small cylinder hone waiting for me.
Just honed out the master cylinder and a lot of the anodising came off way to easily for my liking but it has a nice finish now so i'll put it back together and see if it works.
Hopefully it does and i just saved $400.

 

G

Gibbo

Joined Jul 2017

30 Posts | 15+

Cairns , Australia

Discussion Starter
• Aug 5, 2019

• #12

Taffy said:

there is one called a "Hebo" ....not sure how good it is. sounds like a used one should do you though! I can do a used one for $240 AUS.

Taffy

Click to expand...

Never heard of that brand before.

 

Taffy

Joined Nov 2001

17K Posts | 773+

Ely, England

• Aug 5, 2019

• #13

they are big in trials. probably an Iberian company

Taffy

 

J

Junkie

Joined Jun 2019

105 Posts | 14+

Alameda, CA

• Aug 5, 2019

• #14

I know when I was looking for a master I found that you could buy a Magura master supposedly made to the same specs as OEM for a lot less money vs buying it directly from KTM.

 

Vandor501

Joined Jan 2019

64 Posts | 12+

Sweden

• Aug 7, 2019

• #15

Any pics for follow up? Curious to see how you solved it!

Skickat från min SM-G950F via Tapatalk

 

Taffy

Joined Nov 2001

17K Posts | 773+

Ely, England

• Aug 8, 2019

• #16

G'day Gibbo

have a look at 100466 (9.5)and 100467 (10.5) on my web shop. 143.62gbp which is $258AUS. post would be $18AUS. but you pay in GBP me ol mucker!

cheers

Taffy

 

• 

Reactions: 1 person

G

Gibbo

Joined Jul 2017

30 Posts | 15+

Cairns , Australia

Discussion Starter
• Aug 20, 2019

• #17

Vandor501 said:

Any pics for follow up? Curious to see how you solved it!

Skickat från min SM-G950F via Tapatalk

Click to expand...

Hey Vandor,
I didnt take any photos of the process or final result but it seems to be holding up really well so far. Been on 3 easy rides and probably 10 hours and no problems as yet. I'm going to pull the piston out and inspect it again soon so i'll see if i can get a picture then.
Because it aluminium it hones super quick and theres the risk of oversizing the hole. I had it secured in a drill press with the speed constant and limits set so i didnt jam the hone done too far and do damage. Because the small hone spins fairly fast i didnt get the cross hatching perfect.

Upside is money saved
Downside is now there is no anodising in the bore its actually a softer surface and more prone to damage. The piston is plastic so i would suspect that shouldnt be an issue unless there is some contamination in the oil.

Taffy said:

G'day Gibbo

have a look at 100466 (9.5)and 100467 (10.5) on my web shop. 143.62gbp which is $258AUS. post would be $18AUS. but you pay in GBP me ol mucker!

cheers

Taffy

Click to expand...

Thanks Taffy,
If my 'repair' doesnt work out then i'll probably take you up on that.