Shimano is clearly a leader in making some of the best bike products, but I think brakes have been an area where they’ve always struggled with consistency. I’ve run a few different Shimano brakes over the years. More often then not, they had wandering bite point. I had a set of Saints that it didn’t matter how many textbook bleeds, or Marshy Syndicate bleeds I did - they would wander all the time. I’ve read that the usual culprit is the seals foul easily in the master cylinder. They allow fluid to bypass into reservoir, creating a virtual leak, even though system is fully bled and not leaking fluid externally. This explains why they often “pump up” after several lever pulls.
Further, I’ve heard that the master cylinder walls in Shimano brakes degrade way faster than other brands, exacerbating the sealing issue. This is probably why I was always drawing black mineral oil out of my Saints, even when the oil was only a month old.
April 28, 2022, 10:24 a.m. - Ryan Walters
Shimano is clearly a leader in making some of the best bike products, but I think brakes have been an area where they’ve always struggled with consistency. I’ve run a few different Shimano brakes over the years. More often then not, they had wandering bite point. I had a set of Saints that it didn’t matter how many textbook bleeds, or Marshy Syndicate bleeds I did - they would wander all the time. I’ve read that the usual culprit is the seals foul easily in the master cylinder. They allow fluid to bypass into reservoir, creating a virtual leak, even though system is fully bled and not leaking fluid externally. This explains why they often “pump up” after several lever pulls. Further, I’ve heard that the master cylinder walls in Shimano brakes degrade way faster than other brands, exacerbating the sealing issue. This is probably why I was always drawing black mineral oil out of my Saints, even when the oil was only a month old.