Reverse vacuum bleeding?

Recently I decided it was time I install some new brake lines on my bike. I ordered some in, but rather than OEM replacement lengths, I decided to order a custom set that would give me two lines coming straight from the master cylinder directly to each of the two front calipers. I got them installed, and then realized that I measured poorly and ended up too short. Damn. Already ordered replacements, live and learn.

Anyway, during the whole matter, I decided to purchase a Mityvac  to see if it might help make the process go a little quicker. It seems like it helped, as I was able to get the brake feeling good, and I think some old cloudy fluid was extracted in the process.

But I've also recently watched a video about "reverse" bleeding the brakes, wherein you force a syringe full of fluid up from the caliper to the cylinder. I attempted it, and it was very messy very fast.

It got me thinking, why not fill the system with fluid, and attach a vacuum to the top of the system at the reservoir, and simply suck the air out that way? I've looked, but maybe I'm not using the right search terms, cause it seems like this isn't common. The only thing I guess would be how you actually attach the vacuum to the top, since there are different shapes and sizes of reservoir, but I guess you'd just have to have one that is made for your bike. These days though, it wouldn't be unreasonable to design and 3D print something that lets you cap your reservoir and attach your vacuum hose. 

Does any of this idea make sense? Am I overthinking things as always? Or am I on to something that in theory should work?

Pushing fluid under positive pressure from the top works great.  I use that method with my car.  Use a bug sprayer pump, along with some sort of adapter at the master (that's the hard part).  Works super fast and gets all the air out.

I find reverse bleeding by far the most effective method. 
Three things to remember, completely drain the old fluid out and start with empty system then unbolt the splitter, if you have one, from the bottom yoke and let it hang so that the inlet from the mc is the highest point which ensures you don't get trapped air in the brake light switch. 
Thirdly apply light pressure to the syringe and fill the system slowly. Trying to force the fluid in too quickly will get real messy, real quick as you mentioned. 
If you then feel you need to belt and braces it, cable tie the lever back to the throttle grip and leave overnight to ensure any micro bubbles can make their way out. 

Nessism post=915193 userid=14026Pushing fluid under positive pressure from the top works great.  I use that method with my car.  Use a bug sprayer pump, along with some sort of adapter at the master (that's the hard part).  Works super fast and gets all the air out.

+1 to the pressure bleed. I have a unit that connects to a tyre valve for use on cars, I just need to make an adaptor to fit the brake and clutch resevoirs on my build. I have never tried reverse bleeding on a bike but have done this with the clutch on some cars. For some unknown reason some cars have the bleed nipple below the pipe inlet on the clutch slave which makes them an absolute PITA to bleed, I have connected a hose from the bleed nipple on the front brake caliper to the bleed nipple on the clutch slave then a couple of pumps on the brake and the job is done. The nice thing is no mess as cars usually have a shared resevoir so the fluid is simply circulating from brake to clutch

I also have success with reverse bleeding. I start with an empty system, leave the master and reservoir connected and use a second small syringe to keep the reservoir from overflowing.  And as Warren said, add the new fluid slowly

i'm pretty sure that BMW factory fills their brake systems using a vacuum.
I'll dig up the youtube evidence in a bit. 
I have to finish my coffee first.

I use a vacuum device to fill cooling systems on cars to speed the purging of bubbles in the system.

I tried to build a vacuum system for the master cylinder but it got a bit messy. i was using a refrigerant manifold set and a vacuum pump.. one day i may mess with it again.

Well I finally tried this idea out today, and it worked really well. I should’ve taken a photo as evidence, but basically I bought a spare reservoir cap from my local bike dismantler, drilled a hole in it to fit a vacuum hose attachment point which I had to glue in place, and then I attached the Mightyvac, and applied vacuum pressure. Bubbles immediately came rushing up.

I had already done some bleeding the normal way, so the job was already partially done. But it really felt like this was the thing that took it over the finish line, and it was very fast and easy. 

I reverse bled the front brakes on my ST, much quicker. I did finish off with a couple of lever pulls in the normal way just to make sure there wasn't any air trapped in the caliper. Just done the clutch using the same method on my Dolly Sprint engined special. The other advantage doing it this way on a car is that it's a one man job. I didn't use a syringe though, just a plastic pop bottle with a hole drilled in the lid and a bit off tube stuffed in. Go gently, no mess.

=19.5pxTwo words....speed bleeders. Just keep the reservoir full and pump the lever until no more bubbles then tighten it down. One person job, no mess. Run a hose from the bleeder to a CLEAN container to refill the reservoir. Have them on all four corners of my VW beetle restoration and all of my sons dirt bikes. Look up Goodridge speed bleeders.