78-79 GS1000 Front Master Cylinder Assembly Order?

[srsupertrap]

I purchased a 79 Suzuki GS1000E master cylinder repair kit which includes the following: spring & rubber bushing that fits into the spring, metal piston & o-ring, circlip, rubber boot and copper colored washer. I am unsure were the damn copper colored washer goes. . .

The factory manual does not have an exploded view of the Front Master Cylinder Assembly, it only has a cross sectional view and no parts are identified. It looks to me like the copper colored washer could be the very first item installed followed by the spring or it could reside between spring/rubber bushing & metal piston.

Under Assembly it states "Assemble the primary cup, coil spring and check valve together. Insert this assembly into the bore, taking care not to allow the check valve to become cocked or to unseat the coil spring as it goes into the bore." The illustration & translation suck. I have had this master cylinder mothballed for a while so I have no idea.

[srsupertrap]

Re 850, 750 input?

I am sure this Master Cylinder Assembly is identical to 850, 750's etc. Any takers? I tried Bikecliff's website also, nothing.

[hampshirehog]

The copper disc sits against the rubber bush. The rubber bush has 4 tiny pads on it that prevent the disc sitting down flush.

[Suzuki_Don]

The primary cup goes on the small end of the spring. The spring is inserted into the bore of master cylinder with primary cup facing towards brake lever. Then copper check valve is placed in bore. Then alloy piston is inserted. In other words the copper check valve is between the rubber primary cup and the alloy piston.

Check on your old alloy piston and you may see some tell tale marks from the old check valve.

[srsupertrap]

Re: Suzuki_Don & hampshirehog

Thanks for the advice guys on the copper washer. Much appreciated.

I was having trouble with this 79 Master Cylinder back in 1999 when the brake lever travel would diminish as the brake fluid warmed up. If I left the GS outside, in hot weather I experienced hydraulic lock several times, ie the front wheel was locked up/ wouldn't move and the brake lever could not compress since something had expanded internally in the brake system. The 79 M/C bleed port was not clogged so I replaced it with a NOS 1980 GS1000 Master Cylinder and replaced both the caliper seals and the problem went away. This was probably self induced by me experimenting with silicone brake fluid back in the day when that was the hot setup.

I figured I would resurrect the 79 M/C since I am in the middle of the cam end float modification.