advise please on late bay discs

[Oslo_mark69]

Hi looking for advise !!!!
fitted a set of new calipers and disc to my newly restored "Frank". Took it down to woolacombe for the final Fling and the brakes were rubbing lightly all the way there and back . they seemed not to retract the calipers fully .
Any Ideas why ?? Im running standard early bay master cylinder and no Servo

 

[mattp]

Did you dial in the disc when setting it up? (you should always do this to ensure it is running true as will wear out very quickly if not)

Otherwise what MC are you running and are you sure the flexi hoses are in good gondition?

 

[Oslo_mark69]

Did you dial in the disc when setting it up? (you should always do this to ensure it is running true as will wear out very quickly if not)

Otherwise what MC are you running and are you sure the flexi hoses are in good gondition?

lost me a bit "dial in the disc???"

new hoses
old original master cylinder

 

[mattp]

So are you running a drum master cylinder with discs then?

Dialing in the discs is where you check they are running true using a dial test instrument (and normally held in place with a magnetic stand). They are not vastly expensive either.

 

[Oslo_mark69]

yes standard drum master cylinder

 

[Trikky2]

I am not 100% sure but I seem to remember that the drum master cylinders had a residual pressure valve that is not needed for discs. You can either remove the valve or use a disk master cylinder.

Sorry to be a bit vague but its a long time ago. (maybe a bit of net research on the subject might help confirm or de-bunk this).

 

[5erge]

As per Trickky's post

http://forum.earlybay.com/viewtopic.php?f=2&t=11772&p=261142&hilit=master+cylinder+valve#p261142

Des

 

[mattp]

I am not 100% sure but I seem to remember that the drum master cylinders had a residual pressure valve that is not needed for discs. You can either remove the valve or use a disk master cylinder.

Sorry to be a bit vague but its a long time ago. (maybe a bit of net research on the subject might help confirm or de-bunk this).

They should have 2

I'd just stomach the £40 and buy a new MC that is designed for discs -that is after all what has been fitted