Topic: 1974 cb550 master brake cylinder rebuild-help!

[rpeter46]

Hello boys(and ladies, too.),
     Can any of you help me with this one?  I called my local honda dealership to order a new master cylinder rebuild kit, and they told me it's n/a.  I looked at "old bike barn" and sent in an email, and they said they don't have one for my year/model.  Will someone tell me what kit/supplier they used to rebuild the master brake cylinder for their 1974 cb550?  I would really appreciate it!  Thanks...
Paul

[Gnat]

Don't hold me to this because I am going by my memory (which is way old and rusty )but I think I remember that all the 74 model 350's 450's and 550's used the same master cylinder...maybe...I bought mine for the 350 off eBay..its worth checking anyway.

Gnat

[SHELLFISH]

I just ordered one from Hondapartspitstop.com. $32.00
They had it for a 1976 550K.
I thought they were all the same....no?

Just checked. They are not the same!

If you do the rebuild yourself...get the bent long reach needle nose pliers to assist you.
I got my pair from pit posse. They are not the best but they did help me get that snap ring out.
Do a search about the clip. It's no fun!

[TwoTired]

No. They are not all the same.

Have you tried Western Hills Honda?

[rpeter46]

     No.  Haven't tried Western Hills Honda.  I talked to Chris at Z1 yesterday, and he went through ALL of his old Honda microfiche.  He called me back after a couple phone calls and said he's 'pretty sure' that one that fit the 1976 750/550 was going to work, but it wasn't called out that way.  If you look at parts lists, it doesn't call out "item 33", which is the assy needed to rebuild it. 
     My big question would be to all of you who have already rebuilt your 1974 550's:  Which kit did you succesfully use?

[Gnat]

Told you my memory betrays me sorry for the bad info

GNat

[bryanj]

I have just looked in a very old pair of parts books and all the individual parts from the first 550 are the same as the 750 which accepts the kit part number 45530-377-305. This appears to be the kit to fit ALL the master cylinders except the 77 onwards ones. I suspect the number was just missed out of the original transfer as there is no "kit" part number in the 550 book but there is in the 750 book

[SHELLFISH]

Honda part number 45530-377-305 is the one I used for a 1976 550K.
Worked out well but the biggest pain is getting that snap ring out.
It's a strong bugger!
Just rip the rubber boot and retainer off, the kit has a new boot and retainer.
The rest is pretty straight forward.
Watch carefully the position, direction, of the primary piston. It's critical.
Good luck!

[JBMorse]

That snap ring is a real bugger to get, unless you have the specialty motion pro snap ring pliers



Even with these it's a little tricky.  I had to make a little clamp to compress the piston so I could get in there with the pliers.  Once I figured that out it wasn't bad. 
When I do my braided brake hoses and caliper rebuild I think I'll install a speed bleeder.  For some reason I couldn't get all the air out of my system after rebuilding the master.  After a couple of days I got it, but man it wasn't fun.

[rpeter46]

Thanks for the input everyone!  I got my caliper pulled off and with Chris' help from Z1, I got the correct kit ordered.  He pulled the kit and measured the piston in the rebuild kit while I checked the piston from my bike.  Turned out to be their part#32-1101. 
Yes- even with those pliars, it was still a Bee-otch to get out!  Took four hands and a LOT of patience!

[carpetman.18]

i am currently rebuilding my front caliper and master cylinder on my 1974 cb550 four k. purchased part# 45107323020 piston and o ring for only $85.00 plus 6.00 shipping. honda dealer wanted $110.00. go thru z1enterprize.com. the master cylinder rebuild kt is only 32.00 if i remember right.