The BEST Shimano Brake Bleed Tutorial

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RU-vid is littered with video tutorials on how to bleed Shimano hydraulic mountain bike brakes. However, we wanted to share the real, professional way to properly bleed and flush a Shimano MTB brake that a highly experienced mechanic would perform. This method ensures that all of the bubbles are bled from the system, and also ensures that the dirty, contaminated mineral oil is flushed out and replaced.
In this video, Mike shares some projects around The Lost Co, chats with the shipping crew, and looks to see what bikes the mechanics are working on. Alex then shares how they perform a Shimano brake bleed and flush by doing a gravity bleed to flush out all of the bubbles and old, dirty fluid.
➡️ SHOP Brake Tools - thelostco.com/collections/bra...
🎥 LEARN - How to Replace Brake Pads - • How To Replace MTB Bra...
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The Lost Co // Bellingham, WA
www.thelostco.com
360-306-8827
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0:00 - Intro
0:44 - Bugging the Shipping Crew
1:53 - Mechanic Check
2:44 - How to Bleed Shimano Brakes
15:56 - BYE! WE LOVE YOU!
#mountainbike #mtb #mtblife

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Опубликовано:

7 июл 2024

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Комментарии : 176

@TheLostCo Год назад

Have you ever performed a gravity bleed? Or do you always use a syringe?

@jokermtb Год назад

I do the gravity bleed after seeing World Cup dh bikes bleed the same way

@cjmpaja Год назад

I prefer using a hybrid syringe/gravity bleed method that a local mechanic has thought me. Use the syringe to suck the fluid from the bleed funnel at the lever into the caliper...

@richardkaz2336 Год назад

Just a cheap 5ml syringe.

@Falasi4 Год назад

Yes - Gravity bleed. Relatively infrequent thing I need to do on my bikes so I don't mind taking my time with it.

@brettperchaluk5252 Год назад

Just checking in here - previously I always used a syringe, but the gravity bleed/caliper turning/flip as shown in this video produced a great result on some otherwise stubborn 4 piston XTs that had a wandering bite point issue on my fatbike. Good tutorial!

@outlastproductions 8 месяцев назад

Last step if you really wan to nerd out: Loosen the brake lever and tilt it 45 degrees or as far as you can with out spilling what's in bleed cup, pump the lever a couple times while lightly tapping body with wrench or something. watch a couple bubbles hiding in the lever release into cup. loosen lever and repeat same process 45 deg in the opposite direction. usually find some tiny bubbles fwd and backwards tilt. Then you all done:) OH and I always top off a drop of oil into bleed hole after removing reservoir to be extra sure you don't accidentally trap a bubble in there when replacing that little o ring bolt. keep rag handy for over flow.

@jayhavey1170 Год назад

A tip to prevent air retracting in from the caliper side. Crimp the hose as it's in your waste container and hold that crimp with a soft rubber band. As you push down on the lever, the pressure will bleed out the fluid into the waste bucket and when you release the lever the hose will then collapse into the crimp position and not let any back flow of air travel back toward the caliper. That's also how you do a one-person bleed on a car as well. You could leave the bleed valve open and the pressure of the rubber band will do the work.

@JNineBar Год назад

This is a great method. A good bottle/tube set up the same as in the video is the key to success.

@1oribe926 Год назад

excellent vid. clear and full of useful info. Thanks for the brilliant work

@ctsingletrack 2 месяца назад

I was actually about to attempt a gravity bleed, because I don't have a syringe. I've donr it this way on my cars many times, and was hopeful it would also work on my bike. Glad to see it does.

@ZRMTB Год назад

Shimano brakes are the GOAT…for ease of maintenance and reliability. 👌🏽

@adrianmuller465 Год назад

But when you need to replace seals or small Parts, shimano wont sell you just the Parts. They only offer the lever, tube or caliper as a whole. Thats sad compared to Sram. But sram calipers are just not good for power.

@ZRMTB Год назад

@@adrianmuller465 Good to know. Have not had to replace any parts for as long as I had them. Just bleed and good to go.

@sebastiengiovannelli8556 Год назад

reliability not totaly sure of that , hope or trickstuff, every parts are replaceable

@ZRMTB Год назад

@J B So why did you take the time to click on this video?

@JJ_MTB_15 Год назад

I just did this bleed, worked perfectly. Now we need a SRAM one so I can do my Code RSC's as good.

@Rasedan Год назад

Crucial tips and an entertaining video as always.

@Todd66 Год назад

Mike you are way better at making videos than you realize. This video is gold to me. XTR

@TheLostCo Год назад

Thanks, Todd. That seriously means a lot. Hopefully it comes in handy for your XTR's! -Mike

@jasperbarrett 9 месяцев назад

Awesome! Happy to have seen this 😊

@geckonia Год назад

Appreciate the thorough process ❤

@TheLostCo Год назад

Awesome! Glad you liked it! -Mike

@tomekborucki1120 8 месяцев назад

Have been working as mechanic for 15 years. I serviced thousands of shimano brakes and never used gravity bleeding for mtb brakes. One syringe full of oil pushing the fluid from caliper to lever, the brakes always work with no issues.

@E.T_rode_bikes_As_well 8 месяцев назад

Same here! 😅

@stevesracingbits 6 месяцев назад

Doesn't matter which way you do it as long as it works

@dashofawesome64 6 месяцев назад

I also do think. They should remove the pistons and clean them and at that point new seals. A friend of me got a full suspension mtb second hand from 2008 with Shimano LX M585. I bled his brakes. The front one Was like pure black. But that one was working okay before. Then i did the rear one. It came to the bar. The liquid was clear....done bleeding. Next morning it was sponge again. We both took the whole caliper and lever apart(Do know the guy used it for city use so i bet those brakes haven't seen service in 16 years). The piston(aluminum with plastic inserts) was so dirty, it was stuck on it. Anyway. All cleaned (also we didn't replace the seals they looked good tho, good luck finding OEM ones). Put back together. And they work like new. I believe if the liquid is that dirty there is to much space between the pistons and seals because of dirt on it.

@TRUTHBMXracing Год назад

Great Video, Like the haircut. FYI I'm the mail carrier with the Fox 36 fork issue that called the other day.

@cornishcactus Год назад

I've done all this, got rid of loads of bubbles spent ages getting the last stragglers out of the lever, felt great with the wheel in and the cup on. Undid the cup, full to the brim, fitted the screw, spongy again.

@JNineBar 10 месяцев назад

Same here, similar issues…

@celonetvpn Год назад

Excellent excellent!!! Thank you!

@Biking_with_Akiva Год назад

Thanks for the info 🤙🏾

@2scoops624 Год назад

Excellent content, TIL a few new tricks to try on my next gravity bleed, like that attached catch bottle.

@Pithlitthedark Год назад

Great tutorial, definitly gonna try the gavity bleed next time my brakes need some love.

@TheLostCo Год назад

Heck yeah, they should be feeling awesome afterward! -Mike

@patrickhubner2678 Год назад

Best tutorial!

@RockMumbles Год назад

Nice tutorial!

@TheLostCo Год назад

Thank you! Cheers!

@purpleRider05 Год назад

ive gotta do bleeds on 2 of my buddies bikes soon this is gonna come in clutch

@joncrunk598 3 месяца назад

Thanks!

@sportherz Год назад

Simply the best videos out there, you are amazing..... would be nice to explain some differences e.g. for those MT7's :-)

@BETAeddie141 Год назад

Perfectly timed upload, as i start this week my winter project aka: complete bike overhaul. I cant wait to try this method cause it looks promising! Thank you for the detailed explanation🙂 p.s: loved the hidden dirty joke with the towel 😁

@okatbikes4917 Год назад

The countermeasure spring isn't for top out, it's a negative chamber helper. Helps overcome the friction that exists before the seals are moving (stick-slip).

@okatbikes4917 Год назад

Also, cavitating brake fluid, that's a new one. Read up on cavitation, and what it actually is please.

@paulblo9078 Год назад

No joke you are nearly the only ones on RU-vid showing how its realy done It makes me so aggressiv seeing so many mechanics doing it wrong. Props to you guys

@rickywoods3101 Год назад

As a mechanic I always had best results using a power bleeder pushing fluid from caliper upward and push twice as much needed. It flushes completely and pushes out all debris

@HLS6935 Год назад

This approach is similar to bleeding brakes on a car, working the air out of the system starting from the master cylinder to the wheel cylinders. I was curious why you couldn't just do it the same way with hydraulic brakes on a bicycle... thanks for proving my thinking! No need for buying the syringe, etc.

@CGDreamsTutorials Год назад

Interesting. I thought I was supposed to keep caliper blocks in the whole process, but it seems this is not the case. I take it you push the calipers out just before you put the wheel back on which would push oil back up into the cup till you do a lever bleed?

@shredntread9600 Год назад

So I noticed he did not use a bleed block to keep pistons pushed in. Is this because he has the bleed port open so when he grabs lever its not actuating the pistons since the fluid just flows out? Secondly, he is puts the caliper back together and puts wheel back on. So how does he make the lever feel good? I am assuming since he still has the cup on the master cylinder he just keeps squeezing the lever until the pistons engage with the rotor, and the cup allows more fluid to be sucked to give it great feel. Let me know if I got all the right. Great video.

@peter1987P 8 месяцев назад

@thelostco I just mis the part at the end. What do I do? When you are sort of done bleeding. Do you first push back the pistons in order to install the new pads while the top bleedport is open? Then install the pads (don't touch the lever??) And close the top bleedport? Help! Love this video. Just tried it

@86309 Год назад

sweet!

@Tntdruid Год назад

This is the best guide I've seen on RU-vid, thanks for great guide. 👍

@pirochu666 Год назад

Great video for my XTR brakes! When you said "same concept for other brakes", do you mean even for SRAM brakes? Meaning, (a) would you also gravity bleed SRAM (no syringe), and (b) would you also remount wheel/clipper/pads before disconnecting lever side with SRAM? Just checking before considering this with my Code brakes. Thanks!

@nickireed796 Год назад

Ace vid! Great explanation of what’s happening. You can never know too much when it comes to bleeding brakes!

@TheLostCo Год назад

Knowledge is power, and we want MO POWAAA!! -Tor

@hainman1 Год назад

Superb tutorial So anytime I do a bleed I use the bleed block This kinda shakes things up a bit with leaving the pistons free Also wouldn’t the pads close in on the calliper if doing lever bleed last thing with calliper and pads in??

@TheLostCo Год назад

That is the point, to have the pistons push outward with the pads and rotor in to get it to it's "zero point" to avoid having a slight vacuum on the system which will likely happen if the bleed cup is off when squeezing the lever during final assembly. -Mike

@a8f235 11 месяцев назад

It still baffles my mind that there is no industry standard for this when hydraulic brakes have been around for a very very long time now. Every year I see something new pop up. *_Push it up..._* *_- No, no, push it down!_* *_Up..._* *_- Lala lala laaaaaaaaaaaaaaa...._* ...

@JJ_MTB_15 Год назад

Fricken great video. I will be doing this shortly.

@TheLostCo Год назад

Thanks! Glad you liked it, and best of luck on the brake refresh! -Mike

@patrikkovacs3216 Год назад

Hey guys! Any recommendations on bleeding Formula Cura 4s? Love them, but I'd like to do a bleed soon and get all the performance available:)

@jokermtb Год назад

I shaved 1mm from Shimano bleed blocks to expose the pistons a bit and still allow lever feathering without accidentally pushing free the pistons

@janeblogs324 Год назад

Agreed, if I use blocks as soon as I fit the used pads the lever becomes spongy

@NDemanuele1 2 месяца назад

Quick question, I'm a newbie: How do you know if there is enough fluid in the brake line when you're done? Thanks

@MrPeeceecee Год назад

TRP Evo brake bleed tutorial pls!

@philsson 3 месяца назад

I just did a bleed before watching your video. I did almost everything the same besides keeping the bleed cup on while assembling the caliper. Is there any chance I can put the bleed cup back on the handle to push more oil down? I used a bleed block and now experience I might have too little fluid in the system as my brake pads were half worn out.

@GokkunGuru Год назад

Steve killed it. I love his style.

@TheLostCo Год назад

Steve is the man. Nuff said. -Mike

@gaborlsk 10 месяцев назад

How should I manage the free stroke screw? Should I screw out during the bleeding process? When should I screw back in, after I have closed the system or before? In which position should I set up the brake lever during the bleeding process? Thank you.

@TheLostCo 10 месяцев назад

I just talked to Alex and they recommend cycling the free stroke in and out a couple times during the bleed to move any bubbles it might be trapping! And once you're done with the bleed, screw it all the way in to give you the most crisp bite possible! -Tor 😎

@Slappaisawayoflife Год назад

I'm doing a fs xc build and I can't get the rear brake to lock. My quess is that it is air trapped underneath the crank, I've tried to bleed with a syringe, to have the bar higher and so on. I haven't tried this method though. Do you think this could work?

@axelmoiseslaham452 7 месяцев назад

I do the some but using oil of power steering fluid. What can happeN? Its working good... for the moment

@mtb4512 Год назад

Is it possible to get exactly such a video for Magura MT5 or MT7? No video I know of explains the bleeding of Shimanos so perfectly! Greetings from Germany✌

@mtb4512 Год назад

By the way, the video is just as sweet as the video where the new Grip2 is explained in detail 👌🏽

@MTB2139 11 месяцев назад

I agree and really liked the grip 2 dampener video as well.

@HaggisPower Год назад

Totally get the top-down method for dealing with the dirt, but why not use a syringe to pull it down faster and speed things up a bunch?

@HaggisPower Год назад

Well I bled my 4-pot brakes, both of which had air in them (lever pulled to the bar after having flipped the bike over for a couple of hours). I've got to say the gravity bleed worked perfectly and I used far less fluid than I normally do using a syringe and the pull/push method. I used to find it frustrating trying to drain the system of the dirty oil using a syringe whereas the gravity method made it easy. Thanks for the tutorial.

@BrandonMeyer1641 Год назад

Honestly this method seems way easier and less messy than the syringe method. I’ve had success with both types of bleeds but I’ve never done of the tips recommended in this vid. Need to get a setup like yours with a bottle for dirty fluid attached to the caliper. Do you recommend cleaning the caliper and pistons before or after bleed?

@HaggisPower Год назад

It really is the best method (long time syringe bleeder). Uses far less fluid and makes clean-up far easier

@creatamax16 5 месяцев назад

Hey LostCo. Just wanted to ask, I always screwed out the free stroke to bleed shimano brakes to allow maximum piston chamber filling on the lever do you guys do this or not bother?. Cheers Mike

@shawnoen1029 Год назад

What bleed cup is that? Looks much nicer than the stock Shimano one.

@Justin-ny6un Год назад

That’s the new Shimano one I think released end of 2021 or beginning of 2022. There’s a new syringe too which goes inside of the bleed nipple. Instead of the black plastic ring. I haven’t got it yet, but I don’t like the original Shimano one, tube always pops off the bleed port, also spill fluid out the cup. It can be bought separately or a full kit. The kit includes: TL-BR001 TL-BR002 TL-BR003

@jackiegammon2065 Год назад

Ironically, we were bleeding brakes in the same format over 20 years ago, although without some of the bleed cups etc..

@fullpullmtb Год назад

What diameter tube are you using?

@andrewsiasparks Год назад

I also use rolling papers when there's a void in my life. Oh, you said a role of paper 😂

@TheLostCo Год назад

Hahahaha like I showed on the screen, interpret that awkward statement however you'd like. -Mike

@ianiscaratti4924 Год назад

love the tutorial but if you keep the funnel on with pads and disc instead of the bleedblock you overfill the system and later when the client will press the pistons back it will burst the rubber diphragm membrane in the lever. maby that would be important to mention....

@DleonMar 10 месяцев назад

Anytime you push the pistons out with the new design you need to open the bleed port on the lever. Even a little bit can potentially pop the diaphragm. Unfortunately I learned this the hard way and had to replace it for the customer.

@ianiscaratti4924 10 месяцев назад

@@DleonMar you can easily replace it. It's not expensive or difficult to install....

@kleinkurti Год назад

aint nobody got time for this :D But yes, this might be the cleanest way to bleed

@GokkunGuru Год назад

Can I use Maxima Mineral Brake Oil on my Shimano brakes? If yes, can it be mixed with Shimano mineral oil or should the existing oil be flushed out first?

@TheLostCo Год назад

Great question! There shouldn't be any issue with using the Maxima Mineral Brake Oil on the Shimano brakes but we recommend flushing out all of the existing fluid and just having one mineral oil in there at a time. But it can be super tricky to get all of the oil out of the caliper and then get a perfect bleed on it so sticking with the shimano mineral oil is definitely still your best bet! -Tor

@MichaelRei99 Год назад

Man what did that kid do to his arm? That cast has been on him for a while!! I like watching the tutorials.

@TheLostCo Год назад

I think it was a a fractured scaphoid? This video was filmed a few weeks ago and luckily has their cast off now and has been starting to ride again! -Mike

@tristanwwsd 5 месяцев назад

The Burn, Loot ,Murder crew got hold of him for not wearing their gear.

@aarons1073 2 месяца назад

How would you stop the downward flow on a caliper with a bleed screw (rather than a nipple you can just shut off) so you can get the screw in without a huge mess?

@bens9151 Год назад

So when you do the front brake...same process, except I see a problem. We don't want to leave the funnel in the lever with pads in the caliper, because a spill would risk ruining the pads. Thoughts on that?

@BJJ403 Год назад

Remove the pads?

@jdssurf 6 месяцев назад

Hey i got 8100s Im in a position where if the brakes are close to my grip, and i one finger brake, it smushes my other finger. I got the lever throw all the way out. Do I need more oil in the line or something? otherwise I had to scoot the brakes further away from the grip, but that also puts my shifters kinda far away. What am I missing. If I just 2 finger brake then Im fine but what the heck thanks?

@mountainman7025 8 месяцев назад

The ideas and explanations make sense. Yeah, it's dirty down below since calipers come in contact with rotors. Dirt and other chemicals sip through the pistons time and time. As for me, It's better to begin the process from the top going down rather than from the caliper going upwards, as w/c could allow microscopic dirt to reach the top. I see my old man do this when bleeding his car brakes, but haven't tried it yet on an mtb. Thanks man!

@TheLostCo 8 месяцев назад

Thanks for the comment!!

@joshsavory1825 Год назад

Can you do this for Sram brakes plz

@TheLostCo Год назад

We'll most likely do that one at some point soon! -Mike

@ZRMTB Год назад

Nobody got that much time. Haha.

@tytanjan Год назад

@@ZRMTB it takes me 10x less time to bleed sram brakes because you can use two syringes

@gogovitch66 Год назад

and Magura please! I have my first caliper since 2017 that does not release its air bubbles behind the pistons 😕

@zigzachmtb2821 Год назад

Gravity bleed 💯

@TheLostCo Год назад

Gravity is your friend! -Mike

@zigzachmtb2821 Год назад

@@TheLostCo 🤣🤙🏼

@gergoesapajatszik5171 Год назад

Is it works with magura mt5 calipers too (i think yes)? I have mt5 with shimano slx levers.

@Adam-vm8kp Год назад

There’s no bleed nipple on the magura calipers, has a threaded adaptor for a syringe.

@gergoesapajatszik5171 Год назад

@@Adam-vm8kp oh shit. :D i

@Adam-vm8kp Год назад

Magura sell a bleed kit with everything you need fairly cheap

@gergoesapajatszik5171 Год назад

@@Adam-vm8kp thanks the information. ;)

@DailyMTBRider Год назад

Alex is a wizard.... insert harry potter quote here - ( )

@desertrider325 4 месяца назад

Does he discard the first small amount of fluid before filling the cup? Does he do full pulls with no pad block? Why a pad block in the beginning and then not all again?

@dylan-5287 4 месяца назад

With the system open on both ends pulling the lever just presses fluid out instead of pushing out the pistons. At first the bottom was closed so he had the blocks in to prevent the lever pull from pushing out the pistons.

@JaredHoff Год назад

Video should be titled “CRAZY Shimano Brake Bleed Tutorial” because he looks crazy in that thumbnail 😂 But seriously, always love the videos guys. I need to get up there and visit you guys sometime.

@scotsemmens596 Год назад

What kind of stickers are on that rear triangle?

@TheLostCo Год назад

That's all stock graphics and paint! Pretty cool!

@mariopejovic Год назад

great video, but I got two questions. first, if we don't use bleed blocks and pistons are little out, won't we overfill the system? so when we put fresh brake pads, they will rub on rotors all the time? happened to me when in one shop dude did brake blead with my wheel in, and pads were bit worn out. later it was impossible to put new pads without rubbing so I had to open bleed port on lever side and push the pistons back flush, so new brake pads fitted correctly. second question, how come lever and bleeding cup aren't perpendicular to the floor? from this view (might be camera angle) it leaves possibility for some air to stay trapped into the lever.

@tomasstraka5244 Год назад

eventually they will push the pistons back before closing the lever end for sure, and the bleed port on lever side was the highest point of the system so no bubbles there

@rowerowyja9982 Год назад

You don't have to disassemble anything, turn it around and wait forever... It's unnecessary "fun". Triumph of form over content. Top - a tank with liquid. Bottom - appropriate hose and syringe + negative pressure. The procedure can be repeated several times until the bubbles stop flying. It is possible to correct it at "any" moment - a dozen or so hours of rest + adding a few drops of liquid from the top. Years of practice pay off.

@jubalvw3302 Год назад

Pro tip: for SRAM brakes you can get a "cup" by simply removing the plunger in the syringe. Remember to make sure your "cup" doesn't flop over somehow. 😅

@3CityRide Год назад

There - I fixed it: "Pro tip: for SRAM brakes - switch to Magura or Shimano"

@suggoz Год назад

The "best"

@bdubs1967 4 месяца назад

Can you gravity bleed TRP brakes?

@bdubs1967 4 месяца назад

never mind....saw it at 13:30.

@omtb11 Год назад

What camera gear are you guys using?

@TheLostCo Год назад

For this video and most, a Panasonic Lumix GH5 with a 12-35 f/2.8 lens and pretty much all Røde audio, both camera mounted and wireless mics.

@omtb11 Год назад

@@TheLostCo Sweet, thank you!

@aaronburela432 Год назад

I'm a gravity bleed guy easiest way for Shimano and trp

@Tomzzzzzz Год назад

I've had the least success with rear brake bleeds, so I'm glad this video focused on that specifically. I am going to try this method on my next bleed. This video from Syndicate mechanic "Marshy" is also very good and uses a similar gravity bleed technique: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-piWBVDh1pTE.html

@TheLostCo Год назад

The long hoses on the rear brakes definitely make things more finicky! Marshy and Alex are two of the best in the biz, great minds think alike! -Tor

@user-du6op6qx5s Год назад

why not put a syringe and a hose to the caliber and suck from the syringe down to the caliper?

@lazyac_ 2 месяца назад

Not using blocks to make sure to not put in too much fuild?

@Stomperproductions 11 месяцев назад

No bleed block?

@yoondaman316 Год назад

Why no bleed block?

@alabaster4263 Год назад

Make a sram one now

@britny_f_7086 Год назад

Alex is the best

@su1raM Год назад

Till this video I was using syringe, from now on only gravity

@fetB 9 месяцев назад

why not use Isopropyl to flush. With all that new oil pushing, you mix it with the old

@klstrucker930419 9 месяцев назад

9:53 that's what happened to me. How to avoid it?

@beetrooot1137 Год назад

Air gap in it

@ddtddt2165 3 месяца назад

Stopped watching when I noticed the BLM T-shirt.....

@sebastiengiovannelli8556 Год назад

if you have time you can do hope style aka moto style , gravity , let the oil flow through the hose if you are in a hurry because your wife ask you to came for diner you can do the 2 syringes method and push pull and catch the bubbles , trickstuff style

@Hard_Work_Is_Rewarding 11 месяцев назад

Or... You can just stick to manufacturer's instructions. For some reason there is an obsession with bleed tutorials on youtube. As everything seems to work, everybody and his dog are giving their advice.

@christenrten Год назад

WHERE IS YOUR HAIR?!

@TheLostCo Год назад

Mike's hair has left the chat. -Mike

@lukecico5155 4 месяца назад

I now have 2 bikes with shimano hydraulic disc brakes. I f’ing hate them. Bleeding brakes sucks.

@jupsuu806 Месяц назад

Try magura. Then you love shimano.

@iancraig6070 Месяц назад

A simple job made complicated and expensive by design. It's easier to bleed brakes on a car or motorbike. Wrong design or bad design? Should be better.