How Much Oil - Ultegra Brake Bleed
My bike is 3 years old from new a despite new pads the brakes feel spongy - so I'm thinking of bleeding them with and refilling with replacement oil. I'm confident of the process and going to buy a kit but not sure how much oil I should buy to do both front and rear (road bike ultegra 8020). I have read various things like the (very long) time need to do complete bleeds and how long oil lasts standing still. There seem to be a multitude of bottle sizes one can buy. I don't mind buying a 1ltr bottle of oil but it would grate a little if I used a fraction and 90% was just laying around doing nothing. Any advice on how much I should buy?