Master Cylinder Rebuild

Looking to rebuild my MC as it's leaking a bit but I'm running into dead ends looking for parts or a kit. Looking up parts by the model has been a dead end, I've looked up the MC number and crossed it but still no luck. Really all I need is the parts for the piston so I looked up that part number 43020-1027 and found it fits the following bikes. Any thoughts on a source? Nothing at Z1 (at least on their web) or eBay. I do see NOS pistons on eBay but I won't spend $100 on a part that has 30 year old rubber. These all seem like oddball models.

I know I can swap MC but I want to keep the original MC as I will restore this bike someday, just maintaining now as a rider while I re restore the XJ.

1980 KZ550-A1 FRONT MASTER CYLINDER (KZ550-A2)

1980 LTD II - KZ750-G1 FRONT MASTER CYLINDER

1980 KZ550-A1 FRONT MASTER CYLINDER ('82-'83 A3/A4)

1980 KZ650-F1 FRONT MASTER CYLINDER

1980 LTD - KZ550-C1 FRONT MASTER CYLINDER ('80-'81 C1/C2)

1980 LTD - KZ550-C1 FRONT MASTER CYLINDER ('82-'83 C3/C4)

1981 CSR - KZ650-H1 FRONT MASTER CYLINDER ('81-'82 H1/H2)

1981 CSR - KZ650-H1 FRONT MASTER CYLINDER ('83 H3)

1980 LTD - KZ650-E1 FRONT MASTER CYLINDER

1981 KZ550-A2 FRONT MASTER CYLINDER (KZ550-A2)

1981 LTD - KZ550-C2 FRONT MASTER CYLINDER ('80-'81 C1/C2)

1981 KZ550-A2 FRONT MASTER CYLINDER ('82-'83 A3/A4)

1981 LTD - KZ550-C2 FRONT MASTER CYLINDER ('82-'83 C3/C4)

1982 CSR - KZ650-H2 FRONT MASTER CYLINDER ('83 H3)

1982 CSR - KZ650-H2 FRONT MASTER CYLINDER ('81-'82 H1/H2)

1982 CSR Twin - KZ750-M1 FRONT MASTER CYLINDER

1982 KZ550-A3 FRONT MASTER CYLINDER ('82-'83 A3/A4)

1982 KZ550-A3 FRONT MASTER CYLINDER (KZ550-A2)

1982 LTD - KZ550-C3 FRONT MASTER CYLINDER ('80-'81 C1/C2)

1982 LTD - KZ550-C3 FRONT MASTER CYLINDER ('82-'83 C3/C4)

1983 CSR - KZ650-H3 FRONT MASTER CYLINDER ('83 H3)

1983 CSR - KZ650-H3 FRONT MASTER CYLINDER ('81-'82 H1/H2)

1983 KZ550-A4 FRONT MASTER CYLINDER (KZ550-A2)

1983 KZ550-A4 FRONT MASTER CYLINDER ('82-'83 A3/A4)

1983 LTD - KZ550-C4 FRONT MASTER CYLINDER ('80-'81 C1/C2)

1983 LTD - KZ550-C4 FRONT MASTER CYLINDER ('82-'83 C3/C4)

Hello jayrodoh

Can you please add your bike info KZ/CSR/LTD/550/650/750 to your
user/avatar profile. This would made helping/searching easier/faster for all of us.
Have you a single or dual MC?

Michael

Scirocco wrote: Hello jayrodoh

Can you please add your bike info KZ/CSR/LTD/550/650/750 to your
user/avatar profile. This would made helping/searching easier/faster for all of us.

Michael

Sure no problem. I just updated my signature, is there another place I need to update?

Found something for you.

Single disk

z-fever.de/shop/product_info.php?languag...mass-14x52mm-.html&=



Dual disk

z-fever.de/shop/product_info.php?languag...-15-8x62-7mm-.html&=

Thanks for looking, appreciate your time. Based on the Kawi part numbers referenced in the third pic it looks like it's a piston for early/mid 70's bikes, Z1A commonly.

I did some more detailed searching on the board and have found similar stories on this part but no parts found. I think I'll start looking at kits for same bore MC's and see if I can get a hit. Would be nice to just find the rubber parts.

That master takes an unconventional piston. No idea where to source a new one. You may be able to find some seals and reuse the metal piston part. Or turn a new metal piston on a lathe to match some new seals. Personally, I'd wait on a project like that and just get yourself a new/used master from ebay to get back on the road.

I would buy a new MC, plug, bleeding and have fun.

z-fever.de/shop/index.php?language=en&ca...&cPath=128_179_185&=

@Nessism There is nothing wrong with piston, just the rubber has deformed therefore causing a leak. I'm hoping to find a kit that will work to save this thing. I realize now it will probably be trial and error.

@Scirocco I think I will do just that, get a new compatible MC and ride. Save the original MC for when I get to restoration stage.