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ApriliaWPNC
30 August 2010, 0721
How do electric motorcycles stay in place when parked on an incline? With most ICE bikes you just put it in gear and engine compression does the rest. My Mana GT has a CVT so it requires a parking brake. I am curious how electric motorcycles do away with the need for a parking brake.

Richard230
30 August 2010, 0746
That is a great question, ApriliaWPNC. I have to be really careful with my GPR-S when parking on a slope. It rolls very easily. It reminds me of my Aprilia RS50 (which didn't have enough compression to keep from rolling off of the side stand) - but worse. The only solution that I can think of right now is to carry a wooden block around to place under one of the wheels. If anyone has any better ideas, I would sure like to hear them.

ApriliaWPNC
30 August 2010, 0828
Richard230,

On my Aprilia Mana GT the parking brake is located below the swing arm and is cable operated. (The standard rear brake is mounted above the swing arm.) The operating lever is mounted about where your left knee is when sitting on the bike. I am wondering if the parking brake assembly could be modified to work on other bikes. Obviously a mounting bracket would have to be fabricated and welded to the swing arm of the bike and hard to say how cable routing and mounting of the brake lever would go.

Brammofan
30 August 2010, 0843
I've actually never confronted this before. A wooden block is a good idea, but what about this: I have a length of velcro that I use to keep my cord coiled up under the seat. Couldn't I use that, wrapped around my handgrip and brake lever to keep the brake compressed? Just an idea.

billmi
30 August 2010, 0913
Locking the front brake down like that would have the added benefit of bleeding out any air that might be in the line, too. Extra thanks to whoever posted that tip recently (Ed or Ted, I think) it worked like a charm to get a stubborn bubble out of the front brake on my wife's DR200.

Another approach adding the benefit of anti-theft protection, would be picking up a disk brake lock. They're like over-sized padlocks that lock into a brake disk through its vent holes, preventing the wheel from turning once they press up against the caliper or fork.

Or you could move to the East coast of Florida. No hills, no problem.

BretA
30 August 2010, 1117
While I only had a GPR-S briefly, I used one of these

http://www.webbikeworld.com/r2/motorcycle-lock/grip-lock/

BretA

teddillard
30 August 2010, 1203
Actually, it was Richard- here's my own blog post:

http://evmc2.files.wordpress.com/2010/08/picture-1.png?w=300&h=204

Tried everything and your brakes still are mushy?

Get out the rubber band. …or a clamp. Or duct tape… Even the ever-universal cure Vice-Grips will work.

How?

Thanks to Richard, over on ElMoto.net, I saw this cure for mushy brakes. Clamp the lever tight to the grip… and wait. Overnight is good.

I had the same problem Richard described. When I got the VF500F for my conversion the front brakes were mushy. Once the bike was roadworthy, it was one of the first things on the list to fix, and I got out the trusty vacuum brake bleeding kit. No dice. I did the same thing Richard did, even trying the old-school pump-clamp-bleed-release thing. I even took all the lines apart so I could fill it from zero… still mush. Since it was only one item on the punchlist and the brakes did work, just not really well, I moved on.

(Favorite comment by client when we were photographing an art collection, and hit a piece that was, well, a challenge. ”Let’s pay our respects, and move on…” The client? Paul Matisse, grandson of Henri…)

So, I went out to the garage, turned the bars so the master cylinder was highest, and clamped the lever down. This morning I went out to check it. Rock solid brakes.

Why does it work? Air in the brake lines compresses, fluid does not. When you pump the brakes, you can actually break up the air bubbles, sort of atomizing it, actually, and it makes it almost impossible to clear out without replacing all the fluid in the system. The problem is that, in the system, there are nooks and crannies that will resist being replaced with a conventional bleeding. My suspicion is that in the caliper itself there was a pocket, and as soon as you hit the brakes the caliper started atomizing the air. My solution was to rebuild the caliper and replace the pads- something it doesn’t really need, but easy enough to do once you pull everything apart.

When you have the lever pulled, the whole system is open, from the caliper up to the master cylinder, and if there’s no action in the system, air can do what it does- slowly rise to the top of the system. Once it gets to the master cylinder it can escape, the same way the cylinder feeds the system with fluid- through the valve which is now open. It takes a while for air bubbles to migrate through brake fluid in the closed system… but they do.

Brilliant!

Thanks Richard, and once again, ElMoto rocks!

Richard230
30 August 2010, 1323
Thanks Ted. It is great to know how well this easy bleeding method works.

For locking the brake when stopped on a slope, I like Brammofan's idea of strapping down the front brake lever. My preferred method would be to use a strip of Velcro strap and just carry it around in your pocket for when you need it. I bought a roll at the hardware store which is used to strap plants to supporting stakes. You just cut off enough for your purpose. It is cheap and very light and compact to carry. If you don't need a locking device like BretA uses, this method would be the way to go in my opinion.

electriKAT
30 August 2010, 1406
Back it up against the curb?

gasfreeearth
30 August 2010, 1407
Nice device Bret! Good extra antitheft device also!

BaldBruce
30 August 2010, 2151
plastic zip ties.......

electriKAT
31 August 2010, 0722
Curbs? You must live in one of thme fancy citys with curbs...... :):)

Curbs, running water, dentistry. Yep, a real city slicker.