My new bike has SRAM Code R/s and I don’t like them. My old bike has cheap Shimano 4 pots and I do like them. In both cases it’s the ease of bleeding and feel that I don’t/do like. Are there any other decent brakes that use mineral oil rather than brake fluid. I have a litre of Shimano oil in the garage which is another reason for changing.

my formula cura 4 pot use mineral

Maguras? I bought some of the “Trail” 4/2 pot mixes and they’re a vast improvement over the Deores I had previously(*). They take Mineral oil, though there is some talk of the Magura oil not playing nicely in Shimano brakes – I think it’s OK the other way round.

(*) After only one ride it’s hard to be too thorough in my review.

ETA: And most importantly they came with a sheet of stickers to plaster the toolbox / laptop with 😉

All brakes have their own systems for bleeding – whether or not they’re mineral oil / DOT 5.1 spec doesn’t really affect that. IMHO buy new brakes if you want, but don’t limit yourself to a particular oil type!

If you like the bleeding and feel of Shimano, just get more Shimano?

@doomaniac
I have a complete brand new set of SLX and 4 pot calipers taken off a brand new bike. Front and rear with the Shimano equivalent of the matchmaker schizzle.

Want to swap?

Yes, yes I do!

my brakes are Code R (plural) not Code RS though and they’ve been used so not mint.

These – £60 a whole set! It even boasts the oil type on the reservoir cap 😀
https://www.tredz.co.uk/.Clarks-M2-Hydraulic-Brake-Set_121027.htm

Blimey that’s a good result OP.

I’ve also got some used Code Rs to shift, if anyone else is looking to swap from Shimano 4-pots to Sram.

😀

In theory, could any brake run mineral oil? So long as they were completely cleaned of the dot fluid then I can’t see why they couldn’t run mineral oil. Just a lot of work to get the door fluid out.

In theory but you’d have to change all the rubber components too (seals gaskets bladder etc).

I’ve always loved Formula brakes.

Don’t Magura use mineral oil as well?

TRP

In my experience Magura oil is fine in shimano brakes. I have used it for years in several different shimano brakes without any problems.

You can also use baby oil if you listen to Seth from Bermpeak. 🙂

Don’t Magura use mineral oil as well?

Yep.

Out of curiosity what happens if you put mineral oil in a Dot 5.1 brake?

Not all mineral oil is the same and they are not always cross compatible. Mineral oil is a very generic term and the formulation of two different mineral oils could be very different.

Eg the LMH mineral oil that people often incorrectly recommend for Shimano. In my experience and many others it makes the brakes go soft and impossible to get a solid feeling brake lever.

I’m no expert but I believe incorrect oils can cause seals and gaskets to swell up and deform and not correctly and in some cases the components can start to break down.

This applies to using different mineral oils as well as DOT guilds.

Mineral oil will cause natural rubber and EPDM rubber to swell . Natural rubber is porous and absorbs oil. EPDM is not oil resistant.

https://www.govinfo.gov/content/pkg/CFR-2012-title49-vol6/xml/CFR-2012-title49-vol6-sec571-116.xml

Brake fluid means a liquid designed for use in a motor vehicle hydraulic brake system in which it will contact elastomeric components made of styrene and butadiene rubber (SBR), ethylene and propylene rubber (EPR), polychloroprene (CR) brake hose inner tube stock or natural rubber (NR).

DOT brake fluids are compatible with both natural rubber and EPDM.

I’m no expert but I believe incorrect oils can cause seals and gaskets to swell up and deform and not correctly and in some cases the components can start to break down.

Whilst I’m sure that’s possible, pretty much all brakes are milled aluminium and I would guess the seals aren’t that different, they probably all come from generic 3rd party suppliers eg I doubt Hope make their own seals (otherwise they’d be milled out of Al).

Mineral oil will cause natural rubber and EPDM rubber to swell . Natural rubber is porous and absorbs oil. EPDM is not oil resistant.

I didn’t think anyone used natural rubber for anything anymore as there are cheaper synthetics available.

DOT brake fluids are compatible with both natural rubber and EPDM.

Shame they’re such horrible stuff to work with – although if you ever want to annoy a car owner, splashing a litre on their car will strip most of the paint off it…..

Out of curiosity what happens if you put mineral oil in a Dot 5.1 brake?

The seals will swell (or dislove, crack, otherwise degrade) if you use the wrong one.

You can run silicone oil in DOT system though (but it does need a very thorough rinse through though).

Ask these people.
https://dpseals.com/wp-content/uploads/2016/11/hope-tech.pdf

One reason why natural rubber is still used on car, van, lorry hoses is that it remains flexible at sub zero conditions.

The OP’s post is ironic, Shimano brakes seem to have the most complaints about being tricky to bleed and having inconsistent lever feel. I’ve used a lot of different brakes, Hayes, Avid, Magura, Shimano. Most of my bikes have Shimano now, they are fine when properly bled, but the fluid type was never a consideration. DOT fluid is designed as a brake fluid and works well. The only real drawback is that it damages paint, so you just need to pour some soapy water over the levers and calipers after a bleed to make sure you didn’t spill any fluid. If the brakes don’t have good lever feel, it won’t be down to the fluid type, it will be either not properly bled or some inherent feature of the brake design. Most likely the former IME.

My Sram Guides were a bit more tricky to bleed but other than that, they perform really well. One pair are 7 years old and needed a seal change in the callipers which was easy enough.

My SRAM brakes were always a pain to bleed even with the bleeding edge tool. Plus DOT fluid is nasty stuff.

I agree that all mineral oils are not the same. I read somewhere, I cant remember where that Magura Royal Blood boils at a much lower temperature than shimano oil for example

Plus DOT fluid is nasty stuff.

So is mineral oil. They are both toxic. The big differences are: DOT fluid will damage paintwork; DOT 5.1 fluid has a higher boiling point; if water does get into the system, it will pool at the lowest point in a mineral oil system, which is the caliper, whereas in a DOT system it will distribute throughout the system and have a much less drastic effect on the boiling point. Performance wise, DOT seems to have benefits but both work perfectly well IME. I wouldn’t consider the fluid type in deciding which brake to buy.