I send my bike to a workshop to flush and bleed the brakes. I saw the mechanic do it using the old school way which is using a syringe attached to a clear hose and cable tied it to the front fork tube. He then attached the clear hose onto the bleeding nipples.Opening and closing the nipples when he pump the brakes and letting the old brake fluid into the syringe.
The mechanic did the same way to the rear brake and it really stiffen and rises the rear brake lever. Awesome job...