Brake Fluid

[MrLongbeard]

OK, so excluding racers & track day usage, do you change yours regularly?

It's come up over on the Harley forum that it should be done every 2 years or risk borking the ABS unit and dying in fiery flames
I've got to admit, but aside from the odd topping off I've never done a full or even partial brake juice change

[KungFooBob]

Depends.

If I buy a bike and there's no proof of it ever been done, I'll change it. If not then two years sounds about right, no idea if it borks the ABS valve block if you don't.

It's hydroscopic so it can only be absorbed water in the fluid that cause s problems?

If you change it at home you'll probably never do a complete change on an ABS equipped bike, without the software and cable to get it to cycle the pump you'll never get fluid pushed through the pump. You can change it, go for a ride and make the ABS kick in to dilute it a bit and change it again. I think.

[Le_Fromage_Grande]

My FZ750 has brake fluid from 1985 in the rear brake, works like it should.

[weeksy]

No, but certainly every 2 years would be a minimum for me.

Mtb brakes are 2 monthly

[Skub]

If it looks manky I'll change it. On most of my bikes I've spent time trying to improve the brakes,so old fluid is a casualty of that procedure. I went through gallons of the stuff on my ZZR1100.

It's easy enough to do and BF is cheap,but for road use it doesn't get a hard time anyway.

[Yorick]

I used to get it changed when it was serviced.

[Ditchfinder]

No, but certainly every 2 years would be a minimum for me.

Mtb brakes are 2 monthly

Wait, what you flush brake fluid every 2 months on your mtb?

[weeksy]

No, but certainly every 2 years would be a minimum for me.

Mtb brakes are 2 monthly

Wait, what you flush brake fluid every 2 months on your mtb?

That's correct mate... on both Shimano setups and SRAM.

[Mr. Dazzle]

It's hydroscopic so it can only be absorbed water in the fluid that cause s problems?

Yeah that. The primary concern is that the boiling temperature of the fluid drops. Hence why the cheese gets away with his 30 year old rear brake fluid - it never becomes hot enough to discover an issue.

I suppose there might also be an additional concern with dissolved water causing corrosion or sealing issues in sensitive ABS units.

[Le_Fromage_Grande]

Nearer 40 years old actually, and as I barely use the rear brake on the FZ, it's never going to boil, the fluid is a nasty brown colour, but FZ rear brakes are an utter barstard to change the fluid in without getting air into the system - so while it isn't broken, I'm not fixing it.

BTW while the whole rear brake assembly is from a 1985 bike, it came off a brand new bike in 1985 without being used until I got it a couple of years ago, and since then it's done about 1000 miles, the pads are also from 1985, but had no use when I got it, funny really, it's the oldest part on the bike, but the lowest mileage, most of the rest of the bike has done 65,000 miles.

[Mr. Dazzle]

I was born in 1984, so I don't like to think of 1985 as being nearly 40 years ago

[wull]

Once a year for me depending on usage with regards to track etc and also dependant on what mods I do. For example if I fit a Brembo or braided lines or anything like that then it will get fresh fluid.

[Ditchfinder]

Starting to think I don't change my fluid often enough - as I haven't ever

[Yorick]

Starting to think I don't change my fluid often enough - as I haven't ever

If it ain't broken, don't fix it

[weeksy]

Starting to think I don't change my fluid often enough - as I haven't ever

TBH if you're not experiencing an issue, do you really need to ?

[Mr. Dazzle]

TBF though, if you are gonna experience an issue, it's likely to be the brakes suddenly not working very well 'cause the fluid is boiling - not really the sort of thing you want to encounter when you're not expecting it

[weeksy]

TBF though, if you are gonna experience an issue, it's likely to be the brakes suddenly not working very well 'cause the fluid is boiling - not really the sort of thing you want to encounter when you're not expecting it

I doubt in the real world outside of a trackday that ever happened to anyone.

I'd have thought a brake 'failure' for whatever reason on the road would be more common.... but still, exceptionally rare.

[Ditchfinder]

TBF though, if you are gonna experience an issue, it's likely to be the brakes suddenly not working very well 'cause the fluid is boiling - not really the sort of thing you want to encounter when you're not expecting it

As I pootle rather than rag I doubt I could even get it tepid let alone boil it.

I'm a different rider on an MTB though but have only ever flushed the Dot4 out of a pair of old Hope brakes, all my mineral oil (Clarks / Shimano) sets just get topped off when they need a bleed. Never lost a brake through heat, only crappy shimano piston seals leaking or ripping a hose off in a crash.

The front brake on the Triumph probably needs doing as it's a bit spongy but I keep putting it off as I'm certain the reservoir cap bolts will be seized and it will turn into a ball ache of a job (Can we have an angry spanner waving banana emoji please ?)

[Yorick]

I never had brake problems in 15 years of hauling down 14 stones of gorgeous Yorkshireman from 150 at least 100 times a day.

All on Dot4

[Le_Fromage_Grande]

I never had brake problems in 15 years of hauling down 14 stones of gorgeous Yorkshireman from 150 at least 100 times a day.

All on Dot4

Were your leathers filled with helium?