Rear Master Cylinder Diaphram

[va_blue_stang]

Where can I find a replacement diaphragm for the rear master cylinder cap? My has a small tear in it and I fear it is letting air into the brake system.

[WMarshy]

I think you will have to buy the entire rebuild kit unless someone has one kicking around they are willing to part with... try ebay, they can get expensive though IMO.

[DGXSER]

If your talking about the dust cover on the bottom of the master, that will not let air into the system unless you have bad seals on the plunger to start with. What it will do is let dirt, water, and debris in that will corrode your parts. Take some RTV gasket maker and coat over the hole / slit.

[CaptonZap]

Where can I find a replacement diaphragm for the rear master cylinder cap? My has a small tear in it and I fear it is letting air into the brake system.

If you are talking about the three winged rubber gasket that goes under the reservior cap, go here,

http://www.benefiscal.co.uk/partinfo...J3-25854-51-00

and look at theYamaha models that used that part, then start checking the used and new parts places, online and off.

CZ

[CaptonZap]

Here's more,

If the tear is not to drastic, don't worry about it. If it leaks out, wipe it off , and air on top of the fluid will just cause the fluid to degrade sooner, which would be an incentive to change the fluid more often, which is probably a good idea. One that most people forget, and neglect until some malfunction of the brake system forces them to address it.
The owner's manual advised that the seals be replaced every two years, and the hoses every four, which would imply that the fluid gets replaced at the same time. As long as the fluid level in the reservoir remains above the spooge hole when the pedal is depressed, you will not get air in the system. Air on top of the reservior fluid doesn't count. It can cause the fluid to absorb moisture, but unless you live in a rain forest, or beautiful downtown Yelm, and the temperature changes drastically on a daily basis, the amount of moisture that can be introduced by aspiration will not be a serious problem unless you really abuse the brakes. i.e. "smokin".
And change the fluid regularly, or when it gets milky.

CZ
CZ

[va_blue_stang]

Thanks everybody it is the one that goes under the fill cap.

[DAVINCI]

I know Ben Miller has a couple in the spare parts boxes I gave him, if he's wiling to let one go I don't know.