DoorK / Nodor

[OddJob]

Man, you really are going 'all in' on this one Carl! Some impressive work going on.

And, only a kid from our era would use the term 'husky' as an adjective. I was kind of a skinny kid, so I always had to have the 'slim' jeans. But these days I'm really thankful for my favorite brand, LEE jeans, and their Extreme Motion straight fit tapered leg style. Biking in jeans has never been so much fun!

And now back to your regularly scheduled build off thread....

 

[GuitarlCarl]

Yeah... I wouldn't be caught dead with hair that short.
Anywho... I've been thinking about the center of gravity and the 10 1/2" clearance height of the subframe and the narrow track at 16". Also there's plenty of clearance for the handlebars to turn. I think I'm going to have to make the two halves lean together, or this beast is going to want to tip over. As far as the precision needed I'm wondering about a ball and socket...

I could temp weld it solid and go for a pedal powered spin but if I can source the heim? joints (ball and socket), I should probably just do it. More lean to the right and less but still some to the left. I also just thought of this... Putting the battery under the door frame in its own cage would lower the center of gravity too.

Carl.

 

[GuitarlCarl]

Posed the bike next to an 8' ladder

While I'm waiting for the heim joints to arrive I got a couple of the stickers I've been saving mounted on the wing.

But no real progress while waiting for parts.

GC.

 

[BartRidesEternal]

Posed the bike next to an 8' ladder
View attachment 160529
While I'm waiting for the heim joints to arrive I got a couple of the stickers I've been saving mounted on the wing.
View attachment 160530
View attachment 160531
View attachment 160532
But no real progress while waiting for parts.

GC.

Awesome frame!

This last picture gave me an idea: Can you mount the door behind the left wheel? I like that utilitarian ratrod look, with the wheel next to the door.
For the doors to open you probably have to cut or build "lambo doors"

And with the battery you can probably wire a loud horn.

Just throwing ideas here, love the build and direction so far!

 

[GuitarlCarl]

Door is not going to be an operator...
I'm still waiting on parts and I've got to get going on the battery. It's one of the things I'm missing and I've never played with an eBike before so this will be a learning experience fo sho. If I can source some battery parts and build my own I can save a couple bucks. But I may just buy one and save some time. With battery in hand I can 1. fire up the motor &2. build the battery tray. 1/2" Heim joints are on the way. When they show up swing arms will be assembled and then I'll have to figure out some struts to keep it vertical. I'm thinking the gutted door can't be any heavier than a hatchback, so a couple struts might do but I'm mentally prepared to use 4 if I need to.

GC.

 

[GuitarlCarl]

So does this make sense to you guys?

From the rear view, bike and door are two vertical lines. visualize the swing arms in a row along the bottom edge of the door and back half of the bike as a horizontal line. Now we have a squared off U shape (from the rear view) that is going to want to fall over, one way or the other. Struts are attached in an X shape, top of one side to the bottom of the other. There needs to be enough give to allow the bike and door to lean together, left or right, but enough strut action to help keep it vertical. I'm thinking the struts will need to be partially extended when attached in the neutral / vertical position to allow the lines to lean one way or the other. I wonder how that will effect the struts?

Carl.

 

[kingfish254]

Something about that makes me think there are too many connections and it will bind up or be rigid.
Seams like it should be treated like a flexible sidecar. Try searching around on sidecar flex geometry and see if you can find any details on how they work it all out.

 

[Oldbiscuit]

So does this make sense to you guys?
View attachment 160658
From the rear view, bike and door are two vertical lines. visualize the swing arms in a row along the bottom edge of the door and back half of the bike as a horizontal line. Now we have a squared off U shape (from the rear view) that is going to want to fall over, one way or the other. Struts are attached in an X shape, top of one side to the bottom of the other. There needs to be enough give to allow the bike and door to lean together, left or right, but enough strut action to help keep it vertical. I'm thinking the struts will need to be partially extended when attached in the neutral / vertical position to allow the lines to lean one way or the other. I wonder how that will effect the struts?

Carl.

In theory that should work, but… it won’t. You are relying on the struts to off set each other partially loaded, which sitting still might work. But once you start moving the door top out or in while you’re riding the weight from being off center will overcome the struts. I can’t see how leaning the bike will force the side car to lean the same way. If you were to use a upper and lower a-arm like on a car, both would react the same (leaning left, right or straight up). Think of a parallelogram .

 

[GuitarlCarl]

Something about that makes me think there are too many connections and it will bind up or be rigid.
Seams like it should be treated like a flexible sidecar. Try searching around on sidecar flex geometry and see if you can find any details on how they work it all out.

Yeah it seems like maybe all I need is to be able to lean the bike... Although the last pic looks pretty cool and complicated, rolling the sidecar over and tilting the wheel while staying flat and low. Probably not an option for me.

In theory that should work, but… it won’t. You are relying on the struts to off set each other partially loaded, which sitting still might work. But once you start moving the door top out or in while you’re riding the weight from being off center will overcome the struts. I can’t see how leaning the bike will force the side car to lean the same way. If you were to use a upper and lower a-arm like on a car, both would react the same (leaning left, right or straight up). Think of a parallelogram .

Yes this is exactly what I needed another viewpoint. Thank you @Oldbiscuit I can see where you're coming from and seems right to me, especially the upper and lower arms. A parallelogram is exactly what's needed. There has been one planned for a while, without thinking of it as one and I didn't realize the importance either. I had an idea for an upper arm from the top hinge on the leading edge of the door to the headtube area. My concern with it is the different length. I think the lean would be constant left or right, so the arms need to be horizontally parallel to each other for sure. But what will different lengths of arms do to the geometry? I suppose I'll find out. on the rear half of the frames it will be easy to use an upper and a lower arm of the same length. Once the parallelogram is in place I still think I'll need something like struts in place to help the bike to stay vertical, maybe only from the middle of the door to the lower half of the bike frame to help counter the left turn lean. Now I'm wondering if I need to attach the swing arms from the center lines of each half of the frames? For example an arm attached to the chain stay will drop in relative height from the ground as it leans to the left and raise in relative height on a right turn lean. Maybe the pivot points need to be the same distances from the centerlines to counter each other? Man my head is spinning around trying to visualize it...

Carl.

 

[Oldbiscuit]

Carl, the easiest way for you to see your results would be to get 4 pieces of card board strips and put thumb tacks in the corners to make a square. Start shifting like a parallelogram to see how different lengths will affect it. There are computer programs that engineers use to figure these things, but you’re not building a race bike, I’m sure you’ll see the results easier if you play with it on the table with cardboard before you start welding arms on the bike.

 

[GuitarlCarl]

I have done cardboard mockups in other mediums but never thought to use it here.
I believe wire thru tubing will be a feasible mockup tool. When I get the chance to do it I'll get some pictures. I'm still waiting for parts so I haven't done anything, but soon, I promise.

Carl.

 

[Oldbiscuit]

Any progress Carl ?

 

[GuitarlCarl]

Been really busy but I did get some done today. I even took a few pics. Worked on a guitar some this morning, then went to brunch with a friend. Then I finished putting a small late 1800's pump organ back together. I finally got going on the bike around 1. I came in from the garage around 8pm. So yeah I got some done today...lol.

First off I removed some bracing that I had on the subframe to facilitate mounting what I'm going to call swingarms. The Heim joints came a week or so ago and I got some 1/2" rod and a 12-20 NF die to thread it with, to match the Heim joints. Creating the swingarms, with some backyard measure and cut, thread and assemble, using a angle grinder with a cut wheel on it and my bench grinder, took a couple hours. I had to remove some of the metal from the rod ends with the bench grinder prior to threading getting 1/2" threads on 1/2" rod sounds right but that's a lot of thread to cut especially fine threads. Here's a couple pics...

So I cut some rectangular stock to create brackets to hang the swingarms on. Welded them on the door subframe and tacked the pins that held the sockets (Heim joints) for now. On the bike ends I'll be fabbing up some removable pins so I can take the door and subframe off and cruise it. That means I'll also be making sockets for the electrical bits that are usually hardwired.

GC.

 

[GuitarlCarl]

Well I was on a roll. I had 3 of 4 swingarms done and the upper mounts eyeballed. So I moved on to the the bike side brackets and after some chop cut and drilling two more brackets were ready. On to the wire feed welder... Got them barely tacked on and ran out of wire. Here's a couple more pics...

There's that little pump organ...

Here's where I'm at now. DoorK is hanging from the rafters with it's brackets half tacked. Guess I'll be stopping by Harbor Freight tomorrow. Once I get these brackets done I can hook the subframe up to the bike for a test fit. The swingarms are threaded so I have some adjustments that I can make. I still need to fab a longer upper swingarm. But I have the design in my head. Time isn't an issue yet, even though I need to source a battery, September is far away...

GC

 

[GuitarlCarl]

I'm glad I have the bike part basically finished...

GC.

 

[GuitarlCarl]

Because this subframe design and layout with swingarms is a FAIL!

See the wood blocks? Soon as I pull em out the front of the door dives down. Even with the green wire holding it up, which I figured I could replace with a sleeved chain, it still dips. I know I don't have the upper arms on but I can't see them helping with it at all, except stability when leaning etc. But I do see some major differences between those motorbike sidecars and my hack. One, the wheel is in the back. That's a major problem with the weight of the door, but any other placement would look wrong. Two, the frame is 10" off the ground. Now there will be a lower section housing the battery but it needs the attachment at the bottom of it. The low sidecars were all rigid till they attached to the bikes, with the pivots on the centerline of the bike. So I have a new design in mind and a new roll of wire for the splatterbox. Plenty of time, right? Hehe...

GC.

 

[SwissGuy]

 

[Oldbiscuit]

Carl, the easiest solution that I can see would be to make a box for the bottom that is a rectangle with the Heim joints at all four corners. Of course that would mean moving the front mount on the bike back . Doing this you could get by with one upper bar with Heim joints on both ends that if possible is parallel to the bottom box. If the top and bottom are not parallel or different lengths the outer tire will still go up and down, but the top of the tire will go in or out in the action. This is why I was saying to cut some strips of cardboard and make a parallelogram .

 

[GuitarlCarl]

Haha! Soon as I posted the old one I cut it up and started recycling parts. Fun how arbitrary measurements work flipped around. The subframe turned vertical should give me about 3" clearance. The frame will extend in to the centerline of the bike and attach with a pin or two.

Upside down? I'll fix it at the laptop later... Gotta split...

GC

 

[GuitarlCarl]

Also, a parallelogram by itself won't work with joints at all ends (like two parallelograms in a row) It allows independent movement front and back and I can't have that...
But you got me thinking.

GC.
my cardboard is made of steel...