CB750K6 front brake calliper problem

[PhilWall]

Dear All.  I'm in the final stages of re-building my K6 but have got a problem with the front brake calliper.  When I bought the bike it had been converted to a twin disc with flexible hoses all the way to each calliper.  I've converted back to single disc and bought the Honda hose kit with the final section being metal pipe.  The problem is that when I tighten the nut down all the way into the calliper the metal pipe is still loose. Scottly on the USA forum was very helpful and identified the problem - the steel chamferred insert that should be pressed into the calliper brake pipe inlet hole has been removed.  My question is, does anyone have a spare insert - or know where I can find one, or can recommend a work around?  Thanks for any help! Best regards, Phil

[K2-K6]

Presumably they have converted it to what i would describe as a car type fitment in that the end of the metal pipe would be double swaged to flare out from the pipe side and then back in again for the open end giving a kind of doughnut shape to the end of the pipe that is then squeezed against the bottom of the hole in the caliper.

This is most common in the old slave cylinder brake parts used on cars if you take a look at them.

If that is appropriate, then I'd guess you have to get a bespoke hard pipe made to that spec to provide a means of adaption.

Or get a part turned to bring the caliper back to std spec, although it's possible that people using just std parts would be unaware of what shape to make it as it's not usually removed.

[PhilWall]

Hi.  Thanks for the note.  The plan for this restoration is that everything that goes back onto the bike will be 100% original spec. - either brand new or looking new.  So I'll either need to get an insert or get a caliper body from a breakers and restore it.  Thanks again for taking teh time to respond.  Phil

[Bryanj]

Phil, in all honesty you would be better getting a used caliper and re-finishing it and whilst originality is nice i would use one of Dave silvers stainless pistons as they look the same but will never corrode like the original.