Topic: 4 way brake joint and brake switch help needed.

[MarkM]

Have a '75 CB550 K1 that I'm doing the dual disc conversion on and found a 4 way joint off a 76' GL1000 that appears will suit my needs exactly.  My question is does anyone know if the brake switch on the 4 way will work with the stock wiring plug on my CB550?  And if not, will my stock brake switch screw into the 4 way and work?  Bit worried as this seems like an obvious solution to the brake switch issue (assuming you wish to keep a stock looking hose setup) yet in ALL the posts I've read on the dual disc conversion nowhere did I see a reference to using one of these 4 way's.  Still missing one piece to finalize my conversion-the  MC.  Have been told that MC's from a EX250, EX500, KLR650 have a 14mm piston like the GL1000/1100's, but the ones I find have the brake light switch under the reservoir.  Can I just unscrew that switch and maybe put a plate over it in keeping with the hydraulic actuated one on the 4 way joint/block?  Another issue is I just can't find one cheap, any other inexpensive MC suggestions?  This newbie appreciates any and all help!!  As well ALL/ANY .02 cents worth on doing this conversion is very welcomed.
Thanks all,
M

[doobiebro]

The brake switch is the same, so there is no problem in using the '76 GL1000 splitter.  In fact, I am in the process of switching my front end on my '77K to '78F forks and am using the same splitter.  Your option of using a different master cylinder that includes the brake switch will work as you described.  Or, if you find a '75 or '76 GL1000 master as I did, you don't have to bother.

[GammaFlat]

As a side note... CB750 K8's have a switch in the MC.  All prior CB750 K's do not. 

[MarkM]

Thanks Doobie.  Have you run in to any unforseen problems in your conversion?  Still need to get those long bolts and figure out the instructions on what to do with the "ears" on that speedo plate. 

Gamma,  did the 750's prior to the K8 run dual discs?  Or are you saying a MC off one of those is adequate enough to use on a 550 with dual discs???

[MarkM]

Hey Doobiebro, on that 4 way splitter do you know what that bolt on the top between the MC hose and the brake switch is for?  Is it some sort of adjustment?
M

[754]

 What Gamma is saying is that, with a 78 mc, you need no splitter with a brake switch, or you can run a simple tee.

[MarkM]

Ok, thanks 754.  Can see on a parts fiche where the '78 is a different switch.  Did you do a dual disc convert on your bike?  Am wondering what people are doing to hang the new brake line up with?  Reading a lot of posts on this conversion and don't see any reference on what to do to try and match the little curly-q bracket that comes off the fender. 
M

[754]

I ran dual disc with stock 76 or down 750 mc for years, and it worked fine.

 I was running a custom frame 750, and made my own braided line, with no brake lite switch.. I ran it thru the steering stem to a tee, then 2 45 degree fittings off that, straight into my reversed calipers. No banjos, straight fittings, -3 lines. Not cheap, but looked right...

 Nothing needed to hold lines, they were routed right..

[MarkM]

I followed most of that, up until - no banjo's, straight fittings.  Could you please explain?  I think you mean banjo from MC to splitter.  Banjo's at splitter to calipers, then fittings at the calipers.  If this is right, by fittings do you mean those that are on each end of the stock "pipe"?  If not, then I'm truly lost.    

So is a stock MC on a 75 550 K1 powerful enough for dual discs?  Seems everything I read (hmm) says to get a bigger one like from a GL1000 (14mm).

Kinda wish you'd been on yesterday with my bouncy fork issue, would've liked to have heard what you would have said.

Thanks

[754]

Straight adaptor fitting into mc and caliper..these allow threading on of AN-3 size hoses and a tee. I used 45 degree hose ends (upper end of caliper lines) off the tee because it directs the line to caliper with out a big un natural looking loop or bend.