how often do you bleed your brakes?

[Ximian]

Originally Posted by kolosy

this certainly matches my butt dyno experience with this replacement.. issue is i still have a soft-feeling brake pedal. fresh fluid everywhere, including an ISTA bleed. No bubbles coming out. Only thing I can think of is that I'm down to ~8mm of the original 18mm of DS1.11 brake pad up front. Not sure how that could translate, but still.

Worth noting that pedal feel hasn't changed materially from before my BBK install. It doesn't pump up, the actual braking performance is still fine, but it just feels like it's got a bit more travel than it should, and a bit softer than my other BMWs.

Also entirely possible that it's all in my head. Wish I could find another E9x nearby to compare to :/

There is a DSC adjustment that fixed my soft pedal issue even after the DSC bleed - https://www.m3post.com/forums/showpo...23&postcount=2

[amg6975]

Originally Posted by kolosy

this certainly matches my butt dyno experience with this replacement.. issue is i still have a soft-feeling brake pedal. fresh fluid everywhere, including an ISTA bleed. No bubbles coming out. Only thing I can think of is that I'm down to ~8mm of the original 18mm of DS1.11 brake pad up front. Not sure how that could translate, but still.

Worth noting that pedal feel hasn't changed materially from before my BBK install. It doesn't pump up, the actual braking performance is still fine, but it just feels like it's got a bit more travel than it should, and a bit softer than my other BMWs.

Also entirely possible that it's all in my head. Wish I could find another E9x nearby to compare to :/

Doesn't pump up? Like, you can't build pressure by pumping the pedal? Sounds like a Master Cyl issue to me...

[kolosy]

Originally Posted by Ximian

There is a DSC adjustment that fixed my soft pedal issue even after the DSC bleed - https://www.m3post.com/forums/showpo...23&postcount=2

Ooh interesting. Will have to give that a go.

[Z K]

Originally Posted by amg6975

I have a good friend that was a "Braking Systems Engineer" for a performance oriented car brand and he said that they extensively measured and the difference in expansion between OEM style rubber hoses and braided ones is absolutely negligible and no human could possibly be able to tell the difference. They still use rubber/nylon hoses in six figure performance cars.

I use braided on my fast track car for reliability/heat resistance but any of my other cars and the "normal" track cars get OEM rubber hoses.

I've been using the OEM rubber brake lines for 15 years of track days. I only replaced my front ones because they started leaking where the line is crimped to metal ends. Probably from too much heat cycling and abuse. There is zero difference in brake pedal "feel" with the new steel braided lines. I've seen steel braided lines fail as well so they're not more durable. All they add is a steel braided cover over rubber lines.

I'd say the brake lines are just wear and tear items and just replace them as they wear out.

[kolosy]

Originally Posted by amg6975

Doesn't pump up? Like, you can't build pressure by pumping the pedal? Sounds like a Master Cyl issue to me...

i was more referring to it not being classic spongy / pump a few times get it stiffer, but now that i think about it, if i pump the pedal on my m5 (apples and oranges, i know), it goes from medium to rock hard and i'm sure it's fine since it's basically brand new. on the m3, there's no real discernible difference after a few pumps, it's roughly the same. again, 150k car so a bad master cylinder isn't out of the question.

[bigjae1976]

On stock brakes I bled mine after every track day. I did partial bleeds, I'd use a .5L bottle of Motul for all 4 corners.