Exhaust O-rings

[serafin]

Hi everyone

Does anyone know the thickness and the diameter of the exhaust o-rings?  My dealer wants $10 ea which I feel is a bit steep.  I used my last new set but forgot to measure them befor I installed them.

Serafin

[Platypus]

Just go buy an O-Ring kit like this http://www.allorings.com/oring_kits.htm at an auto parts store.  You'll get several that will work plus a bunch of other useful ones. 

[maddoggy]

serafin, you may be able to use some other o-ring but you will need to know the compound of the original. there are many different compounds used for all different heat applications and pressures. The dealer probably won't know the material so go for the feel. many bearing specialists also specialize in seals as well. for what it's worth, Marty (aka maddoggy).

[mg82]

fmf makes a kit that comes with both o-rings and two springs. i thinks it was like $8-$9.

[Platypus]

I wonder what temps are reached at the exhaust port.  I'll put my money on the FMF and OEM o-rings being the cheaper buna's.  The o-rings I just replaced on my bike were cracked and degrading which is caused by the heat.  Maybe I'll do a little experiment and see if the FMF, OEM, or my box o' o-rings perform differently.  If you do a little browsing around you'll find that even the significantly more expensive rings don't have much better thermal resistance.  I did find a site that said the silicone rings get into the 4000 degree range but they are orange and I have never seen orange o-rings at a motorcycle shop.  I don't think it's something worth losing sleep over.  Put some cheapos in there check them after one ride.  If there are zero signs of fatigue check them again after 5 rides.  My 2 cents.

[serafin]

Thanks for everyones posts.  My intention was to try and get the dimensions so I could find a set of the orange silicon o-rings which are much better product for the exhaust.  I will probably order a set of the FMF o-rings and measure them and go from there.  I'll keep everyone informed of my findings.

Serafin

[KXcam22]

When substituting those o-rings I would suggest that the temp rating may not be as important as diameter.  When I replaced my stock 92 o-rings last year they were worn from vibration but showed no signs of heat stress.  However, the replacements I found (bin at work) had a slightly larger diameter (bareley noticeable) but the larger diam prevented the pipe from slipping into the cylinder.  I had to find some closer in diameter. Cam.

[Spider]

I matched mine up at the local hardware store for about 3 bucks for the pair with no problems.

Dale

[Platypus]

Just wanted to update on the cheap o-rings.  Two play rides and two races and absolutely no signs of fatigue.  So as Cam said it's size that matters :p.  I just took my pipe off and added a bead of orange RTV around each o-ring which supposedly helps prevent vibration in the pipe a bit more.  Do not fear the cheap o-rings they work just fine.