Valves and bike identification

[Zippo]

Hello! Im getting mad valve clatter out of my right cylinder. Its not as bad as it once was. I adjusted the valves per the manual but going down the wormhole on the forums I now am wondering what engine I have. The title says 82' and I have adjustable valves so that should mean SOHC right? But it has 6 gears so that would mean DOHC right? Im just having a hard time with valve noises and I want them to calm down. Take a look at the pictures and help me identify.

 

[tstidham]

Definitely a SOHC engine. The DOHC engines have a valve cover shaped like an H.
https://images.app.goo.gl/hgp68zAnnC66odJq9

 

[Zippo]

So it is! How can I tell if its a seca or special ect...?

 

[tstidham]

I'm no expert on our xs400's, but I'm pretty sure all Seca's were dohc. So probably a special.

 

[CaptChrome]

So it is! How can I tell if it's a seca or special ect...?

The VIN number will tell you what you have. What is the model code (the three letters/numbers after "JYA" on the VIN sticker, or the first three digits stamped into the head stock)? I have the Yamaha VIN list and can look it up. I really should get that info pulled out and posted up here also.... Someday.