[Closed] Definitive Shimano brake bleeding technique

old style fill from bottom is fine, although its also painless just gravity filling from top.

new style is a little bit more of a picky bastard though, and this guide saved my bacon when I was having trouble
http://www.epicbleedsolutions.com/blog/how-to-bleed-new-shimano-brakes/

shonky dp

It's like making apple pie.
We all do it differently but as long as it tastes like apple pie, it matters not how you get there.
Hth...

Incidentally, I remove caliper, pump pads out a bit, bleed upwards to the funnel, rock solid every time.

I have a new caliper but old style levers.

I'll fill from caliper up, everything pointing up so normally caliper off the bike.When you think your done, use the little plunger and repeatedly put it in and out of the funnel hole, it can pull out a few remaining bubbles. Tip from world cup mechanic I read somewhere. Also do a lever squeeze whilst just about opening caliper bleed valve.

I think I tried that epic bleed procedure and it didn't work, the shimano tech-docs method did though. Can't remember what the difference was, and i might be confusing that anecdote with Avid brakes.

I bleed from caliper to lever via syringe forcing the fluid out at the lever. Then lever to caliper (hanging down) forcing the fluid out at the caliper into a little bag.

This video is very comprehensive and clear

, the shimano tech-docs method did though.

Exactly - manufacturer prepares and publishes comprehensive instructions to get the best from their product.

Just follow them.

I can never seem to push the oil from the bottom up so just go in from the top now.

[quote=steel4real ]

, the shimano tech-docs method did though.

I can never seem to push the oil from the bottom up so just go in from the top now.

How come? It should have no resistance at all.

Pads out
Bleed block in
Level the lever
Fit Shimano funnel to lever bleed port
One syringe of fluid from bottom to top
Remove block and funnel, reposition lever
Job jobbed. 🙂

Is it definitively a better method to remove the brake from the bike, or just the caliper?

I'm wondering if it actually helps, or if it's just to minimise the risk of contaminating the pads...?

Fit Shimano funnel to lever bleed port

Don't have one of those.

Don't have one of those.

£6 in shops.

Get one. They're about £4.

Because the definitive method uses one.

I mean I don't have a lever bleed port. They are old levers.

[img] http://media.chainreactioncycles.com/is/image/ChainReactionCycles/prod17135_NC_NE_01?wid=500&hei=505 [/img]

Molgrips, just level the lever, undo the two phillips screws and remove the cover and rubber expansion doofer underneath the cover.
Then

One syringe of fluid from bottom to top

That's what I was planning to do - cheers.

If you like very little lever travel (I do) then file down the little yellow spacer block by a mm or so.

How come? It should have no resistance at all.

I've got a 100ml syringe and I'll be damned if I can squeeze the piston past a few mm... tried every trick in the book. Not had an issue with the brakes bleeding from the top.

Decided to look up an old thread " what is the free stroke screw" that bigjim refers to?
[url= http://singletrackworld.com/forum/topic/xt-m785-brake-bleeding-problem ]Free stroke[/url]

You are taking the top cap off the reservoir when you try and put fluid in yes?

Bleeding from the caliper up sounds a nicer way of doing it, but it's going to be bloody messy with the old levers?

The proper Shimano kit has a little lock-on cover with a hose going to a collecting jar.

[i]If you like very little lever travel (I do) then file down the little yellow spacer block by a mm or so.[/i]

Or use a bit of cardboard and push the pistons out after the bleed. I had to do that on my road calipers.
Always make sure to clear air bubbles from the syringe!

(Blimey epicbleedsolutions sure produce epic instructions!)

[i] but it's going to be bloody messy with the old levers?[/i]

Just pouring the fluid into the chamber on the old levers was always ok for me. Tap tap tap to get rid of air.

Yup, that's always been my method.

I like the idea of using a syringe to push fluid (and any air) up to the lever, but I can't work out in my head how to do it with out fluid going EVERYWHERE.

(and not about to buy the screw on lever cover with tube)

Just wrap a cloth round it to soak it up. It's only mineral oil.

Could manufacture a top cap with a hole in it, like Hope did for their bleed kit.

Just wrap a cloth round it to soak it up. It's only mineral oil.

At that price.. no!

molgrips - Member
You are taking the top cap off the reservoir when you try and put fluid in yes?

Yes

molgrips - Member

Just wrap a cloth round it to soak it up. It's only mineral oil.

At that price.. no!

Well.. I thought about using generic mineral oil.. and then I thought about all the recent stories about seal failures and such with the new brakes.. and I thought it safer to go for the ridiculously priced Shimano stuff. Afer all I might be able to buy a litre of Citroen power steering fluid for half the price, but I only have one set of Shimano brakes so that doesn't benefit me much.

I've been using Castrol LHM mineral fluid fo r over 10 years.
Recently swapped to Shimano Red mineral oil (only because it was on offer and I had a wiggle voucher to use up). Cant say ive noticed any difference that simply bleeding with fresh fluid wouldn't give.
Oh and don't re-use old fluid. It does deteriorate over time and goes through plenty of heat cycles at the caliper end and picks up a bit of crud.

I have the proper bleed kit for the old style levers, where there is a cap that clamps on top of the reservoir etc.. still made a mess. So just reverted to gravity fed method and worked fine.

The newer levers with the funnel that attaches to the top is a much better solution but still most the time I'm lazy so just use gravity fed again.

Also another recommendation to use Shimano oil. I tried the Halfords stuff and the lever feels heavy and sluggish compared to Shimano also the seals failed very quickly soon after but not sure if the Halfords oil sped that up or they were just on the way out anyways.

Citroen mineral oil and Shimano are just different coloured, same stuff

If you like very little lever travel (I do) then file down the little yellow spacer block by a mm or so.

You can do the same without overfilling by removing wheel and pulling lever and advancing the pistons.

Both methods temporary though until pads wear.

Citroen mineral oil and Shimano are just different coloured, same stuff

Link?

According to Shimano

Shimano has never approved a third party brake fluid to be compatible with our brakes and we never will.

Shimano claim otherwise.

Do you know for a fact or did you just read it on the internet?

https://www.bikerumor.com/2013/04/11/tech-speak-brake-fluid-break-down-and-implications-for-road-disc-updated/

[b]Can consumers use fluids other than your specific branded fluid in their brakes?[/b]

[b]Shimano:[/b] Absolutely not, mineral oil is an unfortunate term to use because it is so vague and generic. The term mineral oil can describe a lot of different compounds. It’s kind of like the term salt, which refers to much more than just table salt. Most of us are probably aware that the mineral oil that you buy at the drug store is not the same as the mineral oil we use in brakes, but that extends to different brands of mineral oil brake fluid as well. We should really call it “proprietary brake fluid” but I guess that doesn’t have the same ring to it. I can tell you with absolute certainty that Magura fluid will destroy Shimano brakes in a very short amount of time. I’ve seen it happen several times. The rubber seals in the system have to be specifically designed to interact with a specific brake fluid. If you use a different fluid, the seals will interact differently. Specifically, when you put Magura fluid in Shimano brake, the lever feels spongy and the pad contact point changes because the square edge seal at the caliper is breaking free from the piston at a different time.

There are third party companies that make mineral oil brake fluid and it says right on the bottle that it is compatible with all mineral brakes. Shimano has never approved a third party brake fluid to be compatible with our brakes and we never will. How is it possible that one fluid can work in both Magura and Shimano brakes if Magura fluid destroys Shimano brakes?

Everyone should read that Bikerumour article.

Well I've used Castrol LHM in all my Shimano brakes over the years (probably 10 years+) without any obvious issues.
My current M775s have been on the bike for 8 years and they were second hand when I got them.
So I can say with some confidence that in my experience LHM is fine to use with Shimano brakes.
Obviously Shimano are going to say only use their own stuff, they have a vested interest in doing so.

They're my brakes.

Shimano say 'use our oil!' so I use their oil. Really don't see the point in messing around to save a few quid.

I can never seem to push the oil from the bottom up so just go in from the top now

I had this problem when I first tried bleeding my Avid brakes by following a you tube tutorial. After lots and lots off faffing I realised that I had been following the (american) video so exactly that I was trying to bleed the front caliper to rear lever.

[i]Do you know for a fact or did you just read it on the internet?[/i]

Been using it for so long, I can't honestly remember. Although last bleed on my road bike brakes I used Juice Lubes mineral oil.

epic bleed kit. bleed form calliper up, don't have to take brakes off bike, can do it in 5 minutes and get a good bleed every time

So I can say with some confidence that in my experience LHM is fine to use with Shimano brakes.

Shimano used to be very reliable didn't they? And then they started having seal problems more recently? So perhaps your 8 year old brakes are ok with any old oil, and the newer ones are more sensitive?

(actual question not being snarky)

You might be right, although given the number of reported problems when people haven't changed the oil I suspect its a shimano issue rather than a fluid issue.
This is one of the main reasons why I reluctant to chnage up from my M775s!

I found LHM to be a tad slow on the levers in the past, and since then only use shimano oil.

Shimano 1ltr is only £13 so not expensive.

But the thought I might make it worse or more likely by using non-standard oil against recommendations for the sake of what, £6 or so made me choose Shimano.

Shimano 1ltr is only £13

It is? I paid £12 for a tiny bottle!

I have used LHM on my SLX and Zee brakes. They worked OK for a period, but never really got the bleed perfect. I picked up the LHM stuff from Halfords, in the bargain bucket section when I was frantically looking for fluid. Was about £3 for a litre.
Assuming it's related, but I also had pistons leaking and master cylinder sticking (when cleaned it was full of gunk).
Switched back to the proper stuff and been better, I do still get the wandering bite but only when pads are very low.

I use this German site for bike parts, when i need to stock up on bit and pieces, but you do have to get over min over value, although even with carriage its still cheaper than CRC for some parts. funny enough i use a Germany company for pet food too as its cheaper than the UK, obvisously not the same one 😉 .

https://www.bike-discount.de/en/shop/workshop-1884?currency=3&delivery_country=190

Shimano 1ltr is only £13

It is? I paid £12 for a tiny bottle!

I use this German site for bike parts

Better stock up then before 2019!