Shows how to replace brake fluid using the reverse bleed method. If done correctly it's quick and easy to bleed air out of the system. Be careful not to spill brake fluid over anything as it's corrosive.
A tip that is popular when bleeding mtb brakes is to pull on the syringe before you open the bleed valve. You’re trying to create a vacuum in the syringe, when you do you will see loads of small air bubbles form in the fluid, flick the syringe with your finger to get them to float to the top of the syringe. Just another little thing to get that nice firm lever feel.
When I want to learn how to do some type of maintenance on my bike, I don't even use google, I come straight to your channel and look here first. Thank you for producing excellent tutorials, I love how clear and easy to follow your instructions are. Also, I'm fairly sure your accent makes you at least 100% more credible. 👍
Thanks! This workedd great! I tried everything before I reverse filled it like you recommend. I literally worked on these brakes for an entire day. I saw your video when I was about half way through with day 2. Much appreciated!
This is a great video. The only thing I could add is to make sure your brake line always has an upward trajectory, not bend downwards to your reservoir otherwise air could still get trapped.
very good brother, I'm from Brazil, and his care and maintenance tips like these are very useful, as here the cost for off road bikes is high. Nothing better than taking care of our own
Excellent vid.. nice and clear. May I add that topping off the brake fluid to the max level should only be done when new pads are fitted. Topping up to the max level on the reservoir with part or well worn pads will only cause you headaches later when you come to change the pads for new ones because the fluid can overflow from the top of the reservoir as the piston/s are pushed back into the caliper/s and the fluid level rises making a mess, unless of course you drain some excess off prior to fitting said new pads. (not everybody follows this practice and the reality is brake fluid leaks through the tiny air holes present in the underside of the cap/lid that are designed to allow the seal/diaphragm to take up the slack as the level falls and the pads wear) Not being critical my friend just some helpful advice if it's any use.
The caliper piston is roughly 3 times. Larger than the master cylinder piston. . With that said when you push the caliper piston in just look how much pressures your are putting on the seals & cups , roughly 12 mm caliper piston. I have ruined even new master cylinders with that method. What to do is open the bleeder on the caliper to relieve the pressure you create when pushing the caliper piston back in. Or just take your chances.
You can completely avoid this by opening the brake bleeder when pushing the pistons back, i do not understand why people jump through hoops when its the easiest method. And using a pair of calipers to measure brake fluid level is just psychopathic.
Worked like a charm. I tried reverse bleeding and was still was getting bubbles after many many attempts. The key was using the zip ties to keep it sealed the entire time. The zip ties wouldn’t work with the clear 1/4in PVC tubing I got from Lowes, it was way too thick/stiff to clamp through with the ties, kept falling off. What worked for me was silicone tubing like you commented. Ended up using the tubing made for breastfeeding pumps. It looks like it’s too small for the bleeder valve but it stretches over it with some effort, then it clamps down good because it’s so soft/thin. Depressed the caliper pistons with a flathead screwdriver(twist it for the leverage) then pushed through 4 reservoirs of fluid and got the lever super firm the first time. Took me about 10mins total!! Thanks! Hope this helps someone else. Wish me luck with stoppies.
Just went and got my brother a 06 636 I’ve just been trying to bleed his front brakes spent like 2 hours and still had so much air. Got pissed and started to do more research found reverse bleeding went out got all the stuff went to reverse bleed and still the brake didn’t feel stiff enough. Started searching through the comments and found this one went out got silicone tubing and worked like a charm brake finally feels perfect!
@@iulianc9037 the fluid acts as a grease seal for me. Only crack the bleeder 1/4 turn. Actually just did it 2 days ago, only took about 15 mins and the brake lever is very firm
I can't thank you enought. After 10 attempts to bleed my brakes the "normal" way I wasn't able to build pressure. Doing it like this it was done in 5 minutes. Thank you so much!!
I did it this way yesterday I injected the fluid and brake perfect 4 times! The best way I know. Of course, everything has been reset and cleaned and a new liquid in the whole system! Best regards! Good movie!
brilliant.After pumping the break lever like over 100times to get the bubbles and break to firm up this is far superior method.Learn something new thank you
Same technique works well for reverse bleeding hydraulic clutches. Nice vid. May I add, after emptying the reservoir, I like to cover the reservoir with a cloth, because sometimes the new brake fluid can sputter through the tiny orifice in the reservoir and tiny drops can splash out the reservoir. The cloth prevents that splashing. Or, just add in a tiny layer of new brake fluid after taking out the old fluid.
Used this method today. After doing some research the internet is riddled with brake bleeding horror stories, and I was hesitant to do it on my own. This method was so easy and worked instantly. I have piggybacked brake lines on my front, and worked from the furthest path to cylinder, I didnt even have to inject from the 2 nd closest. I found the rear brake had a bit of air, maybe because its on a horizontal plane. But i then after did the normal method of squeeze-open-close, and it got rid of any bubbles. This IS the best way to bleed brakes for flushing or new lines.
Thankyou! Got an old BMW K bike that's tricky to bleed the normal way. Another tip tighten a cable tie after all this on the brake lever/ handgrip overnight to sharpen up the brakes.
You missed a step. That bleeder valve is above the brake line fitting. When you are pushing fluid in through the bleed screw, air can remain trapped in the top of the caliper ( in the upper piston bore and resettle in and around the bleeder passageway). You can't push the fluid through there fast enough to guarantee you get all the air. Before you called the job done, you should have pumped up the master cylinder and cracked open the bleed screw again to expel any remaining air that may still be in the caliper above the brake line fitting. Yes your brake may feel "ok" and function, but why not add the final step and make sure the air is expelled.
Good tip. Although I’ve never had an issue reverse bleeding the front brake as shown in the video, what you’re suggesting would only take a few extra seconds to do and help ensure a full bleed.
To use a medical term, you can flag the syringe at the end to verify there is no air. As in draw the syringe back and see if there is any air trapped and at the same time bring the fluid down to the fill level on the M/C if necessary.
74 Thumbs Down????? What is wrong with people? Mark, you have the most informative Instructional Videos out there. Keep up the great work. Big Fan. I do enjoy reading through the comments as well as you can pick up additional tips. Some of the complaints drive me crazy though. Reminds me of the time I was watching this History of Fleetwood Mac show on TV and there was this part where Santana was saying “ I told Peter he should have done this, he should have done that”. I almost threw the TV through the window! Just finished the bottom end video. Couldn’t put it down. Think I will skip the actual rebuilding of the crank though. A little over my head. I’m better at taking things apart as compared to putting them back together properly.
ON my motorcycles, I could not build pressure when I did traditional way, with this way it was quick,,, I think the reverse bleed for brakes and clutch is the best way, it build pressure in the system when you do it this way as well,,,,,good video
Always remove the calliper,and pads,hang the calliper so bleed valve is at the bottom,proceed with syringe,then once all.done flick the lever a few times,add correct amount of fluid in reservoir,clean thoroughly with brake cleaner and reassemble,great vid.
Utilized your brake bleeding method as described, worked perfectly. Did the same method for the hyd clutch, same perfect outcome. Watching this and other of your tutorials, notice changes to your machine, on this one the Impact wheels. Am always chasing maint on my KTMs to keep them near optimum condition for long rides big on fun low on issues. KTM should have a contract with you for this good work. Thanks again.
This is the best way to service the brake if it’s single disc system Quick and easy The vacuum method that most shop use takes longer to bleed from completely empty systems
Great vid 👍 Doing the brakes on my BMW R1100RS but the ABS II unit seems to be stopping the fluid flow using a Mityvac. The front reservoir doesn’t empty at all using this method. Hoping a reverse bleed will do the trick.
Brake cleaner is so toxic and is not needed. Use soap and water mixed in a spray bottle. Use small scrub brush when cleaning. Also, brake cleaner around the brake pads will dry them out and they will squeak horribly. Great video mate, you are the best of all time with repair videos and thank you so much for everything!!! Without your vids we would lost and doing things incorrectly, much appreciation for all your knowledge you've shared, etc.
Good on you ! Thanks for the reminder to use pressurized reverse feed. You can also use water to clean up - water displaces and neutralizes brake fluid.
Hi mate great vid as usual, one tip I use is when finished bleeding is to fill the master cylinder up to the top so when I put the lid on it overflows with fluid, this means there is no air in with the brake fluid. Then if you crash / flip the bike etc no air can travel down the brake hose. 😊
Would you make any special modifications to the brake line while bleeding as on my 2013 KTM 300 xc the brake line sticks up and over the master cylinder at any angle the bars are at. Sometimes I'll loosen the top banjo bolt so the line is angled lower than horizontal then reposition once I've bled the system.
Tried this, and like another commenter, I couldn’t get the fluid to push to the cylinders, it just wanted to come out the bleeder screw threads. Also, I’m glad it didn’t work because my front bleeder had a bunch of dirt in it and by bleeding down from the master, it flushed all the dirt out instead of into the system. So if you do this method, make sure your bleeders are cleaned out. This reverse method did work great for me on the clutch though.
If you can’t push fluid up it indicates that the master piston is not in the correct position (is not fully out), or something is broken. Yes, it’s important to clean off any dirt from the nipple before reverse bleed. If the nipple cap has stayed on all the time during use it should be clean inside. Pleased to hear it worked well for your clutch.
I've been doing it this way since 1985. Some bikes (every Japanese bike I've owned) will suck air in around the bleeder screw threads. Don't open the valve any more than needed to get fluid to go in.
You want to check the level of fluid compared to the amount of wear on the brake pads. That way when you change pads you won’t over flow the master when you compress the pistons.
How does the air traped in the upper part of caliper travel down to brake line that enters the caliper at its middle to go upstream to fluid reservoir?
Thanks for sharing and your time. I also grease the ""threads"" on the brake bleeder itself so no air can leak or get sucked past them. As you know threads have play from one to the other.
i always push the brake pistons back when i change it because when the pads are worn out very ugly black fluid stays behind them even when new brake fluid is up in the reservoir
You will get some leakage at the bleeder with this method because the bleader's threads are not fully sealed. Maybe wrap the threades with tefelon tape before starting. You might find that a bit of safety wire twisted about the tube at the bleeder makes a more secure connection. Always have a wet shop rad handy when messing with brake fluid.
Great video! I'm struggling to get new fluid into the line. It just leaks at the nipple thread with a lot of force on the syringe. Drain valve is 1/2 turn open or better. Thanks!
Maybe a suggestion : Using conventional method, bleed old brake fluid by pressing brake lever and opening and closing ur bleed nipple. It may clear the blockage which may be present. Then use your reverse brake bleed method using syringe method. I think your bleed nipple is blocked from old fluid gumming up some debri.
Thanks for this, I bleed my front brake with no problems :) The rear is giving me trouble, I opened the rear fluid revisor and opened the bleed valve, but when I try to push new fluid in there is a lot of resistance. When I push harder the fluid pushes out just after the bleed valve (coming out the threads I think) do I need to open any other bolts on the brake line? what am I doing wrong?
Not so far. I've used the current syringes for about 4 years and they're fine. I purchased them in an auto parts store so they're intended for you with brake fluid.
I started using this method after purchasing and installing the Rekluse Left Hand rear Brake that comes with two syringes.. Only difference is the Rekluse Master Cylinder doesn't have an external reservoir but has a separate bleed Nipple on the lever assembly that the other syringe fits on to and the excess fluid and air goes into.. Great method and video.. Thanks for sharing..
Thanks for this! How hard are you pushing the syringe? I back-bleed mine yesterday and had to press the syringe with my knee to move fluid. Bleed nipple was open, no obvious blockages.
I have to press hard, but nothing crazy. Maybe it’s an issue with the syringe you have. Reverse bleeding is popular with mountain bikers and I know there are some nicely designed syringes for that. I haven’t tried any other syringes than what is shown in the video, so don’t have any specific recommendations
Just come across this video, brilliant fair play. Need to do my Vespa soon, got the kit ready, just hope I don't want to replace full brake system 🙏being stood here six years. The resovoir is quite empty at moment. How much brake fluid will it take?
does opening the bleed valve allow air to enter the system between the caliper and the valve screw? I've noticed I have to open the valve screw quite a lot before I can start pushing fluid in. Wondering if air is getting sucked into the system. How much are you opening the bleed valve - 1/8 or 1/4 turn?
I don't know what all the fuss is about doing it this way (reverse). I think it's also more difficult to get rid of all the old fluid if trying to have fresh fluid. It's easier to let it drain into a container from Gravity. I just pumped the brake lever to pressurize, then crack open the bleed port to let fluid out the bleed port with the brake lever held in compression and let it drain out into a container. Close then close bleed port, then release lever, add fluid to reservoir when needed to stay above ports and repeat. This takes less tools. I didn't need two syringes and carefully fitted hose on the bleeder port. This is pretty much the standard way to bleed car brakes. I flush the entire system of old fluid in the process and get a firm brake lever when finished.
The advantage of the reverse bleed method is if there is air in the system it's much quicker to get a full bleed. If there is no air in the system then the traditional bleed works fine too. In my experience the reverse bleed is much easier to do on your own as compression of the brake lever is not required. My experience of reverse bleeding is that it's quick and easy to do. Traditional bleeding not so much (particularly if there is air trapped).
@@TokyoOffroadI’ve put about 100-150ml of fluid through my front brake system today and it improved but it’s still spongy - I suspect the reverse bleed is going to use the same or less fluid and also be more likely to have a successful outcome first time so less faff. I tried the Stretch Armstrong DIY approach then got help from the mrs to pull the lever and it was like a scene from the Chuckle Brothers 😅
This is a good method for single brakes, but I don't think it will work so well for twin brake calipers, since you won't know when you have old or new oil in the reservoir. This is easier to see when you push through from the top as you will see the new oil colour in the pipe.