O-Ring sizes

Does anyone know the metric o-ring sizes for the fuel rail and Seca 750 anti-dive? I know len has them, and I do send him plenty of my business. But I saw a metric o-ring kit (assortment pack) at the parts store for like $2.50...thought I'd save myself some coin. Had many very small o-rings...no disrespect to our parts guru, but I'm always up for saving money when quality is not compromised.

 

are the O-rings fuel resistant?

 

Will check

 

if they aren't Viton or fuel resistant, then they would be pretty much pointless (for your application) unfortunately.....

 

http://www.mcmaster.com/#o-rings/=ojcyuk
most of those kits are buna-n, mine have been in there about 4 years

 

The kits in the store are probably either neoprene or Buna-N (nitrile) and unless it's labeled, you won't be able to tell the difference. Problem is... If it's neoprene, I would avoid it. It's just not good enough, especially in a very low maintenance application like the fuel rail O-rings that you have to pull the carbs and split the rack to replace. Nitrile (Buna-N) would be fine, but unless the composition is identified on the package, it's a crap shoot.

And in the unlikely circumstance that it's Viton, the package will announce that loudly.

 

Yea know the guys are gonna kill me but I came across the same problem with my xj750 and I just used a gas resistant sealant. Hasn't leaked yet.

 

What sealant did you use? Do you have a brand, name, or pic?

 

Thanks for a lot of really good advise, but could somebody answer the question?

 

I purchased two sizes and evaluated the two:

First size was US size #010 which is a nominal 1/4 ID and 3/8 OD (actual .239 ID and .379 OD)
Second was metric size 2mm x 6mm which is .236 ID and .394 OD

After evaluating those two sizes, I went with the metric 2mm x 6mm. It was a snugger fit than stock, but with a little silicone lube it slid in fine. If you can only find US sizes, the #010 seemed to be closer to the fit of the original stock O-rings, but that may have simply been because my originals had been deformed from years in application.

It seems unlikely that they used US spec O-rings in this metric application, but I had a hard time finding a metric O-ring with the exact same cross section as the original.

Sorry for the previous non-answer.