cure for MK3 front master cylinder

Status
Not open for further replies.
Joined
Oct 28, 2014
Messages
1,996
Country flag
I have had 2 front MK3 master cylinders rebuilt with the reduced diameter piston. There seems to be little or no options except to rebuild the original. There is a problem now with too much lever travel with the lever now needing to travel further to push the same amount of fluid. The brake lever ends up just short of the grip and if the rubber line expands under the increased pressure, you've got problems. My solution was to have a braided steel line made up at the local brake supply house (the benefits of living in a city) and then I made a spacer plate from 1/4" aluminum plate to fit between the MC and the throttle/switch cluster. It works great with the added benefit that with a small bit of mill work it is now possible to access the inner mounting screw for the throttle which makes it a lot easier to remove or adjust the throttle/MC.
 
If you want more lever, you can eliminate the spacer and use the non-MkIII lever. I had a similar issue on the SS clone (see Wanted; Brake Lever). Mine was a bit more pronounced because I don't have the MkIII switchgear, which mounts the m/c a bit farther from the grip than the older type. I also have the Madass sleeve-down mod. Now that I have the older-type lever (thanks, Bob Z.) everything works as it should. If you find the older-type lever is too far from the grip, you can modify the plunger tang and stop to suit.
 
Status
Not open for further replies.
Back
Top