hardware store o-rings..

[aaronb]

incredibly stupid question, but what are they made from?  you know the shiny black type. 

i accidentally damaged one of the two on one of my fuel line fittings this weekend which resulted in a tiny stream of gas pissing on the exhaust from the vertical cylinder.  good thing i noticed it right away after starting the bike this morning.  so i found the sliced o-ring on the fuel line fitting, and got a replacement from the hardware store up the road.  no mention on the drawer what they were made from (Buna-N, Viton, etc).  it is currently working just fine, but should i replace it with one from the dealer ASAP?  the original was also black but felt a bit softer.

I asked the guy at the hardware store what they were made of and in a dead straight face he said 'rubber, primarily' i don't know if he was being an ass or was just completely stupid 

[Howie]

No way of knowing, black O rings may or may not be gasoline compatible. 

[Langanobob]

Aaron,

The standard o-rings from hardware stores are usually buna-n, which is compatible with gasoline.  But, I don't know of a way of telling for sure, so it wouldn't hurt to get a real one next time you're near a dealer. 

[NAKID]

You could always buy another one and soak it in gasoline. See if it breaks down...

[ducatiz]

i have a supplier who sells all kinds of o-rings (and z-rings, x-rings, quad-rings) in buna, nitrile, EPDM and a bunch of other exotic stuff.

i can post their info when i get home, they are a big company but will sell small quantities.  they have plenty of metric stuff too.

i got Z-ring seals for an older Pantah clutch (of course, no long available) and they matched it perfectly.  the EPDM material is far superior to the natural rubber and is DOT 3,4,5 compatible.

[hypurone]

i have a supplier who sells all kinds of o-rings (and z-rings, x-rings, quad-rings) in buna, nitrile, EPDM and a bunch of other exotic stuff.

i can post their info when i get home, they are a big company but will sell small quantities.  they have plenty of metric stuff too.

i got Z-ring seals for an older Pantah clutch (of course, no long available) and they matched it perfectly.  the EPDM material is far superior to the natural rubber and is DOT 3,4,5 compatible.

Now that right there is pure porn for a gearhead!! 

[aaronb]

i have to run to the dealer soon to pick up an oil filter, i'll just get a new o-ring or maybe even an entire fitting then.  it wouldn't hurt having a spare fitting in the box, im always worried i am going to break those thin plastic sides when squeezing them. 

i think the hardware store o-ring will be fine but if it should fail in the future it will leak fuel onto the exhaust.  i don't think 50 cents is worth risking the entire bike over.