Can You Use New Valve Seals on an Old Cylinder Head?

While the answer might seem obvious, this isn’t the first time we’ve been asked if you can use new valve seals on an old motorcycle cylinder head.

Partzilla’s motorcycle expert John Talley hosts live Q&A sessions on our YouTube channel every Friday at 3pm Eastern. In this session, John was asked about installing new valve seals on an old cylinder head for an unnamed dual sport motorcycle.

New valves old cylinder head

New Valve Seals on Old Motorcycle Cylinder Head Q&A

Can you use a new valve seal on an old dual sport motorcycle head if you remove the bottom seat and seal (washer and seal)?

John Talley: Definitely. Whenever I open up a top end, I’m going to replace the valve seals while I’m in there. They’re cheap, and basically made out of rubber. And they’re in a really harsh environment, so that means they’re going to — it’s not if, but when — fail. They’re going to harden up and not do what they’re supposed to do, and oil’s going to go past the seal through the valve guide and start washing down the head. And guess what? It’ll turn into a mosquito sprayer, lots of smoke. So yeah, absolutely, do that all the time. In fact, like I said I wouldn’t open up a head and not replace the seals.