Fuel line size

[imcgyver]

Hello repaired my vacuum petcock and found a bad fuel line, got a 1/4 id thin wall line and it seems too small, is there a metric size or will 5/16 id line work better?
Thank you for your time and response. Ron
1981 Yamaha XS650 SH

 

[5twins]

The stuff that YamahaXS650.com sells is a perfect replacement for the original thin walled line. They call it a 1/4"I.D. but it's actually a bit smaller (about 6mm). It's wonderful stuff .....

https://yamahaxs650.com/product/black-rubber-fuel-line/

I like it so much, I buy it by the 25' roll, lol .....

https://yamahaxs650.com/product/black-rubber-fuel-line-1-4-x-25/