Front brake reservoir O-ring size and material ?

[Rijko]

Does anyone know the material and size of the large o-ring for the front brake cylinder ?
OEM nr. 59686-33600

I need to rebuild approx. 20 of them, and prices vary between 10-25 bucks a piece.

Size looks to be approx. 50mm dia, 2mm thick, but i have only old ones.

I can find these in Nitrile for less than 1 buck a piece ...



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[Nessism]

EPDM O-rings are needed for brake fluid. O-rings are commonly measured by ID and thickness. Measure carefully using a high quality caliper. Don't measure the old O-ring, if possible, measure the parts being sealed. Plan on at least .5mm of O-ring crush in the application.

[Rijko]

Thanks Ed !
May just order 1 OEM one and take it to an o-ring specialist to be sure.

[Big T]

Thanks Ed !
May just order 1 OEM one and take it to an o-ring specialist to be sure.

That O ring has been NLA for a number of years

[Rijko]

That O ring has been NLA for a number of years

Have you checked Ebay recently ?

There are dozens of ads for them ...

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p4432023.m570.l1313&_nkw=59686-33600&_sacat=0

[Rich82GS750TZ]

I think the point is, he’s trying to get them for considerably less than $25 each. Understandable since he needs 20 of them.

[Rijko]

yes i am Rich, for 1 bike i would not have bothered but for a 20 piece project like this it means 500$ vs 20-some $.
That's not pocket change for me