Hydraulic Disc Brake Bleeding - Hayes Dominion D.O.T. Fluid

This video will review the bleeding procedure for Hayes Dominion brakes using the Park Tool BKD-1.2 Bleed Kit.
Questions or comments? Leave them below!
See all our disc brake videos in our Disc Brakes Repair Help playlist ▶︎ • Repair Help: Disc Brakes
Video contents:
00:00 Introduction
01:00 Tools & Supplies
01:55 Preliminary Info
02:22 Bike Prep
04:30 Bleed Kit Prep
05:46 Caliper Bleeding
07:46 System Bleeding
10:52 After Bleeding
➤ Tools & materials used:
• BKD-1.2 Hydraulic Brake Bleed Kit (DOT) - www.parktool.com/en-us/produc...
• PP-1.2 Hydraulic Brake Piston Press - www.parktool.com/product/hydr...
• PS-1 Disc Brake Pad Spreader - www.parktool.com/en-us/produc...
• TL-1.2C Tire Lever - www.parktool.com/en-us/produc...
• Hex & Torx-Compatible Wrenches - www.parktool.com/category/hex...
• Appropriate D.O.T. fluid
• Zip ties
• Safety glasses and gloves
• Isopropyl alcohol and rags
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• Visit our TH-cam Channel: / parktool
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➤ About Park Tool:
Since our founding in 1963, Park Tool has been the leading name in bicycle tools. Our TH-cam channel is an extension of our mission to be the ultimate resource for mechanics and riders of all skill levels. Here you will find comprehensive repair help tutorials for a wide range of components and processes, as well as troubleshooting guides, tips and tricks, and information on the latest Park Tool products.

[@edwardojr2838]

I don't have these type of brakes, butt very thorough video with good explanation. Thank you Park Tool

[@stevenlee2347]

Thanks. Just completed a successful bleed on my A4s.

[@jasonpantha6819]

Thank you, bleed was successfull with the sram bleed kit without O ring. appreciate it

[@paisfr]

Merci Beaucoup Thank you ☀️😁👍

[@brianboake8884]

I’d love one on Promax Deciper

[@zygmuntthecacaokakistocrat6589]

My PS-1 is a 20mm cone spanner, since i hardly ever use it for hub servicing.

[@MarcinKrokosz]

I lost the little rubber thing which is on the cable and comes to the lever covering the linkage (hose - lever). Where can I find only this little part without having to order a full set? Could you please help me with this little-big problem?

[@seatpostman]

Is 1,5 Nm enough to preserve tightness of the ports on the caliper? In my case when tightening the screw to 1,5 Nm (new set of brakes) I was having leakage from both ports. I had to tighten the screws much stronger and for 2 days I haven't seen any leaking drops. Is that only in my case or has anyone had this same issue?

[@ltsTJ]

I just installed these on my bike. During bleed process, I noticed that a ton of oil was leaking from the master cylinder bleed port during pressurization and air nearly freely entered the system when applying a vacuum. Any idea what that could be? I have looked in and don’t see any o rings in the bleed port, but the brakes are brand new. I also checked the other master cylinder and there is no o ring. Not sure what to do

[@parktool]

Its possible that the o ring on your bleed fitting has a cut in it or that it is not seating. Inspect the o ring on the bleed fitting and test the syringe/ bleedfitting / adaptor setup by covering the end with a gloved finger and drawing a vacuum to be sure there is no leak in the syringe setup. There is a possibility of a leak in the lever but that is fairly low probability.

[@ltsTJ]

@@parktool no leak in the actual syringe set up but the bleed kit I have doesn’t use an o ring on the bleed fitting, I just googled around and it seems that every other kit (including yours) uses an o ring there..

[@barryge]

@@ltsTJ I had the same issue as you today. Did you find any solution to the problem?

[@ltsTJ]

@@barryge yeah I took it to a bike shop 😂 their syringe sealed. Waste of money but I love the brakes. They had to rebleed the front 3x

[@barryge]

@@ltsTJ haha oh boy 😂 love the breaks too. Thanks for the response!

[@jamble7k]

is it not a good idea to keep the caliper bleed ports facing up? fluid fell out on the last step

[@parktool]

You can try. There will be a slight bit of loss because you end on compression of the syringe. This leaves a tiny bit of pressure in the system. The little bit of fluid coming out is becasue of that and is done to prevent air from entering.

[@JohnSmith-tw2hn]

In the Hayes bleed video, they say to always keep the caliper bleed ports facing up while bleeding. I took my rear A4 brake off my bike, mounted it on an old handlebar, and clamped the handlebar in my repair stand, then I taped the caliper to the base of my repair stand so that the bleed ports were facing up. The problem with keeping the bleed ports facing up is that the brake hose does not run straight upwards from the caliper to the lever, rather there is a loop under the caliper, which is a place where bubbles could get trapped. I think that is why Park bleeds with the ports facing down: it means any bubbles can travel straight up the line to the lever.

[@jamble7k]

​@@JohnSmith-tw2hn I bled mine last year with the hayes kit and can't remember what I did but they are still going strong 😁

[@thephoenixcycle8854]

@10:02 nope 🙁

[@miromomo4705]

Same here, I love how the breaks feel, but I can’t get a short throw, no matter what I do.

[@2wheelman]

a lady had her brakes jammed up. we didnt know how to free up the breaks there is no release on those kind of brakes. seized up issue.

[@notanomad9320]

Were the pistons possibly seized up at the caliper? I had that happen on my fat bike that sat for months after riding in winter and exposed to salt. I was able to loosen them up and they work fine now. Good luck.

[@simonchaddock3694]

I have shimano 4pot they are boss