Motorcycle Repair: 1981 yamaha xj 750 seca

Question
where is the rear brake fluid reservoir located?

Answer
Hello Thaddeus,

My friend, either your bike is modified or it is not a Seca...
Secas never utilised hydraulic rear brake. They all had mechanical drum brake.
Actually no XJ up to '92 600 SecaII.

So if yours does have a disc brake, I obviously can't help you.
Follow the route of the hose from the calliper to find the master cylinder, and then from the master cylinder to find the reservoir.

I hope I've been helpful.

Best Regards,
Lazaros.

P.S.: I would love to see a picture of it, if it does have rear disc brake mod...