Viton/high temp Orings

[Cannonball]

Captain the design from cagiva is poor to say the least. 2 orings seal between the stub pipe and the exhaust. One against the end of the stub and the other between the stub shaft outer diameter and exhaust outer pipe wall. Good old springs really are all that provide any real sealing capability by compressing the first oring.

Has anyone tried Chemraz® / Kalrez® / Simriz® (Perfluoroelastomer) orings in a similar high temp situation?

[chew]

O-Ring Material Guide

O-Ring Fluid Compatibility Guide

[Captain Starfish]

Any reason (I haven't seen the setup) you couldn't hard mount them with copper crush washers? Permatex Copper HT RTV sounds like a bloody good solution too!

[richarde]

I'm running Viton on my RGV. I'm aware of the hydroflouric acid issue. I suspect it won't be a problem as these seals aren't actually exposed to flame, but I'm planning on wearing gloves next time I go near mine.

[Cannonball]

Thanks guys.
Captain Starfish I am using the orings in my cagiva exhaust stub connection. The originals are fantastic but rare as hens teeth. Athena have been the next best, arrows were crap.
Went to Statewide Bearings and they said viton. I get 3-4 months before I get the 2t splooge pushing past hardened degraded orings.
If anyone has other suggestions I would be keen to listen. Guys on the uk cagiva forums just say fill the gaps up full of copper high temp silicone sealant and use stronger springs(was the first item done).

[Captain Starfish]

Can? Does. In significant quantity. As well as Carbonyl Flouride, a phosgene analog.

Deadly, deadly stuff. Which is why we use it in oxygen clean breathing equipment.

- - - Updated - - -

Worth talking to the guys at Transeals. You've got choices including Bunyl N, Viton A, PTFE, EPDM and a bunch of others and you may find a better match than Viton for the working conditions you have in mind for the seal.

[Rich...]

Transeals...

They are like 10 times more expensive than Nitrile, but when it's in a spot where it will see heat then I'd rather pay $5 for an o-ring and know I'm not pulling the bike apart again in a few months...

[Shady7/8]

And can release hydrofluoric acid if burnt.

[Captain Starfish]

Transeals +1

But Viton is expense. Hideously, arserapingly so. Often 10x the price of the equivalent Buna-N or nitrile piece.

[Cbr1k]

Transeals in Welshpool

[al.ramsay]

I bought Viton seals for a cbr250rr & vfr400 from a LiteTek.co (http://www.perthstreetbikes.com/foru...-honda-161875/)

worth a look

[Seb]

Coventrys used to sell them pretty cheap. Not sure if they still do but may be worth the phone call

[Cannonball]

Hi folks,

Just putting out there to see if anyone has found a cheaper source of viton or high temp orings for exhausts. Over paying through the nose at the local bearing shop so hoping there were some other alternative sources SOR.

Cheers