Front Master Cylinder Q?

asphalt900 wrote:

Forgot to mention. If this bike is a rescue and has been sitting a long time, the lines/splitter could be clogged-up too. This will hamper any bleeding. Ya might pull the pull the caliper banjos off and verify fluid presence. This is if you don't have any brake vacuum equipment.  

The good ol' chunky fluid trick!  Never good.  And if the lines are the originals, change them immediately.  They are sure to be lined with scum.

P1010652 by nessism , on Flickr

 Thanks to everyone who chimed in. I was trying to keep it stock-ish.so I bought this master cylinder from eBay and a rebuild kit from BrakeCrafters. I am into this paper weight for about $100. Life is a Lesson. Guess I will put it on the shelf as a reminder and buy a new one, LOL.
 Again, Thanks to everyone!
 Steve

Dont give up yet on the master. Have you tried the good old trick to let it selfbleed?  you just tie the lever into the throttlegrip than fill up the reservoir and let it sit over night with the lid off and bleeder screw shut. If it is pitted in the bore ,But not too bad ! you can hone the bore using a
fuelhose tube with wetsand paper taped on it with dublesided tape. The small hole is for air venting out by the way.

The old self bleeding trick Rolf, ha! Yes that can work but because he has those LTD bars it can put the master at a tilt so filling master is mandatory. Also because of the tilt you'll often find an air pocket within the line/banjo coming from master. This air pocket has to be removed before that syphoning self bleeding event can occur. That sandpaper on a stick trick can help but like mentioned earlier some of these had a metal sleeve liner. No way to get out the deep pitting in those, pointless. That's why Tokico dropped that thought in quick order.  

that style of m/c isn't very good. the top leaks. finding an alternative can be a pain. for bleeding. get a speed bleeder. or bleeders if it's dual disk. raising the caliper helps. 

asphalt900 wrote:

The old self bleeding trick Rolf, ha! Yes that can work but because he has those LTD bars it can put the master at a tilt so filling master is mandatory. Also because of the tilt you'll often find an air pocket within the line/banjo coming from master. This air pocket has to be removed before that syphoning self bleeding event can occur. That sandpaper on a stick trick can help but like mentioned earlier some of these had a metal sleeve liner. No way to get out the deep pitting in those, pointless. That's why Tokico dropped that thought in quick order.  


 

Yes you are right .It helps to have bike on sidestand and turn frontwheel  to the left to get the reservoir high and as level possible.I agree about the banjo bleeding cheers !

Sandpaper won't remove pits.  It will help with staining, though.

EX650 master works great for dual disc bikes.  The mirror lug is the proper thread also.

O forgot about the bore. Yes wetsand paper works great to remove burrs and pitting in a aluminium master i done it some times. In a metal sleeve it will be more difficult. I think i heard about a companay that  install stainless sleeves some years ago. But why did Tokico not make stainless sleeves !!

Rolf i haven't a clue why the metal was used? Of course it's a common theme on just about every car on the road. I use KARPs in California to SS sleeve all my masters, i'm sure there's plenty of other companies that do it too. Yes H1V, those rectangular or trapezoidal type Tokicos always seem to weep-out eventually. And those trapezoidal ones were metal bore too, that's why they are soo expensive. Any moisture will rot out the bore, mostly on bottom of bore where the water sits. I suppose the failure could be contributed to owners NEVER flushing out/replacing fluid as called for though. From my experience maybe one out of ten are useful for reuse. And as Ed mentioned, sandpaper will just knock down the staining. Too much sanding will result in a rocking piston and failure anyway. I never sand mine but use an extra long drywall screw with the screw head cut-off so i can chuck it up in a drill. Then wrap the threaded section with 000 steel wool making sure the screw is centered in wool packing. Shoot a little lite oil down the bore and go to town. You don't want a rough RA (roughness average) in that bore, a drawback from using sandpaper.  

Rolf1976_KZ900 wrote:

O forgot about the bore. Yes wetsand paper works great to remove burrs and pitting in a aluminium master i done it some times. In a metal sleeve it will be more difficult. I think i heard about a companay that  install stainless sleeves some years ago. But why did Tokico not make stainless sleeves !!

Agree with Clay ref maintenance, following the correct fluid replacement schedules will all but eliminate rust internally in the hydraulic system. Stainless sleeves would be nice but it all comes down to production costs

Wow, I thought I was the only one who was having a time bleeding my front stoppers. I don't feel so bad now. I did chuck up the MC in my mill and honed with 220 grit at light speed with light oil and now just the lightest sign of corrosion.  On the bench it pumped up pressuer so I am back to bleeding.....