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[Kill3rT0fu]

So I just tried to bleed the brakes this weekend. Had to order a vacuum pump because the traditional method wasn't working well. No matter what size tube I was using, it wasn't tight enough.

So I'm wondering if any of you have ever tried those "easy bleed" one way valves, or have any other suggestions. I finally got the brakes bled...but DAMN I made such a mess and would like to avoid that in the future.

[slant911]

Have not tried them on my Zero but have successfully used speed bleeders on ATV's and motorcycles in the past.  They work very well and make the job pretty painless.

[Demoni]

With proper technique I have never ran into issues hand bleeding a moto. Having the right tools available will make the experience go a lot smoother. Not saying your doing it wrong, but this is the workflow that works for me.
Good fitting (6 point) thin profile box end wrenches are the way to go. Slip the wrench on the bleed nipple before attaching the hose.
I find 1/4" Id hose fits snugly over most bleeder nipples but using a wire clamp like the one pictured below can help. I like thicker wall silicone tubing as it has a bit more flex when installing on the nipples. The hose will stretch over time, just trim a little off the end if things start to feel loose.

For a 100% dry system the trick is to get fluid to fill the line first. Start at the MC bleeder, just open it and repeatedly pump the lever till you see fluid in the hose. If the bike does not have a bleeder at the MC you can slightly crack open the banjo bolt to accomplish the same result.
Once that is done connect the hose to a caliper and again just pump the lever. Don't worry about introducing air at this point. When you get fluid flow to the hose do the same thing on the other caliper.

Now that the lines are full you can work to get the air out. Again start at the MC and work your way down. Be aware that if the path of the brake hose has any high points air bubbles can collect at these points and be hard to push down to the calipers. Wiggling the hoses and gently tapping the MC can help knock any micro bubbles loose. 

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As for one way "speed bleeders", I have had mixed results. Stiction between the ball bearing check valve and the nipple can allow small amounts of air back into the system. I have used vacuum pumps before and find they help with getting fluid into a dry system, but do nothing to speed up the process of removing trapped air. An option I can 100% recommend is a reverse bleeder, these pressurize fluid and force if from the calipers up through the MC and into the reservoir. The air is pushed in the direction it naturally wants to go (up). The drawback is these devices are expensive and only work with empty circuits.

[Richard230]

I just replaced the master cylinder and brake hose on the front disc brake of my Royal Enfield. I was using my usual vacuum pump but it was not working to get the air out of the system. But then I tightened up the upper brake hose fitting a little more and after pumping the brake handle a few times, almost immediately the lever feel became hard and no more air came out of the caliper bleed valve. So apparently I was getting air past the brake hose fitting where it attaches to the master cylinder. Something to think about when running into hydraulic brake bleeding issues.

[Kill3rT0fu]

With proper technique I have never ran into issues hand bleeding a moto. Having the right tools available will make the experience go a lot smoother. Not saying your doing it wrong, but this is the workflow that works for me.

This is the issue I have. I didn't want to buy yet more tools I'll only use once. I already had a 3/16 hose and 1/4 hose. The issue I had was the nipple wasn't tall enough to decently fit a hose AND the wrench. I think even with a slim wrench I'd have issued. I tried a hose clamp on the nipple and that still didn't help. Ideally a longer valve would be perfect. But I figured if I'm replacing that, why not look into speed bleeders.

[Demoni]

The issue I had was the nipple wasn't tall enough to decently fit a hose AND the wrench. I think even with a slim wrench I'd have issued. I tried a hose clamp on the nipple and that still didn't help. Ideally a longer valve would be perfect. But I figured if I'm replacing that, why not look into speed bleeders.

Yea that's frustrating... Can you post a photo of the stock bleed nipple? My only experience is with Brembo calipers, interesting to see what the JJuan ones look like.
Also if your front brake lever is adjustable for length of pull make sure you adjust it so the lever is as far away from the bar as possible. This ensures the valve in the MC is going through it's full stroke.

For reference this is how much the Brembo nipples protrude.