Let's Build It Already!

Upon pondering some transmission thoughts, I think that at least for now I will setup a system to switch the motors from series to parallel depending on A) speed and B) steering. It is far easier to do this than to mechanically deal with huge reductions and shiftable drivetrains (other than an internally geared hub).

So series wired for startups and slower speeds. Once past a certain speed, will switch automatically to parallel, and not drop back to series until a couple MPH slower than that setpoint. The hysteresis will prevent the switching system from chattering and blowing stuff up. :)

I will need to learn to drop the throttle when the shift occurs, so I don't end up with sudden bursts of speed. I will probably put a light and maybe a beeper on there to alert me to an imminent shift, maybe 1/2 second before it happens, which should be enough to react to until I get a feel for it.

Since the main reason I wanted series motors was so that I could get an electronic differential for turns, it means that turning would need to be done at slower speeds in order to get that differential. For gradual curves it may not matter; have to test that. For sharper turns, such as from a N-S road onto an E-W one, I will probably need that differential.



Hmm....maybe a much better idea would be to build up the second 2QD and tweak them both to run identically when matched with their own motors, then use separate controllers with one throttle, compensated for an electronic differential by having a steering sensor that changes the proportions of left vs right motor throttle. It'd be more electrically complex, but also simpler in a number of other ways. It also leaves me with redundant controllers as well as motors and drivetrains, which is a nice feature.

I think I already have all the parts for a second one, including another metal enclosure (from an old external harddisk) similar to the Jensen inverter case I am installing the first one into.

This also means I can leave the Curtis on the CrazyBike2's motor, to which it is more suited (given that motor's short-term power capability).



I could not sleep last night (again, it's a common problem) so in between dozing just long enough to know I dozed as my head hit the keyboard, I looked up tilt-steering (leaning) trikes, all over the web.

I found a little information here on ES, which eventually got me links to links to links to a place called Jetrike, an open-source recumbent bike / trike project. The creator of it has plans and construction notes for a bike and a couple of tested trikes there, and some of the stuff looks very interesting. The most interesting part is that he has run simulations for the designs to see what would "really happen" before actually building anything. And has data tables and stuff for a few critical types of dimensions and how to work them out for a particular design. The trikes are deltas, but he started on a tadpole according to his pages there. I'd be super-interested in seeing what he comes up with.

However, the link to that project is broken, and there are no updates to the site that I could find since late-ish 2007. There is also a discussion link, but skimming thru it's archives I don't see any indication that he has proceeded with that project at all, which is very disappointing, as he did good work on the previous versions, and has hard data on why some things should or shouldn't be done, and how they might be improved to fix problems reported with various ways of building trikes (including fixes for rear-steering trikes, which are notoriously unstable and potentially very dangerous, due to flaws in layout of the tested versions, apparently).

Anyhow, I have many more ideas on a tilting trike, but I am still not confident at all that I could design something around that concept and make it work safely and reliably. Not with the stuff I just happen to have laying around, anyway.

There are others around as well, and many images and a few clear videos of some in action. I may be able to learn enough to actually design one of my own, though first I need to learn enough about the math involved to grasp the solutions in my head so I can come up with stuff without having to actually sit down and do all that math (at which I really suck).


I think I need to just build the thing first and get experience with a trike, then start working out version two that will have more features on it, probably including tilting.

I might even go ahead and build a pedal-only trike first, just so I can get that part working, and get a feel for ergonomics of the design based around my riding, and THEN work out a replacement for the front wheels/forks that lets me use the motors on there. I've been putting off this trike thing for so long because I didn't have this or that or a way to figure such and such out, etc., and I am really wanting to just get it STARTED!

More Trike Thoughts

spinningmagnets on ES is looking out for internally-geared hubs, which would greatly simplify the switching-gears on the front wheels, and ought to be able to take the nominally 300-350W per wheel I would be putting thru them, as long as I set it up to cut power during shifting.

So I will probably build the front setups simply using regular rear hubs on both front wheels, and any multi-gear drivetrain I come up with for temporary use will be easily removable. I still need a ratio change of around 1:5 to get the 20MPH top speed, from the gearbox output that's intended to directly drive wheels half the size of the ones I'm using for 8MPH.

I have been pondering a way to swap the gears in the gearboxes so that they output closer to what I want to start with. I cannot remember exactly what ratios they are inside for which parts, but basically the main reduction is from the motor shaft's helical gear to the first right-angle gear in the box. Then that has another gear on the same shaft that meshes with the output gear, which is on a lever-type clutch to disengage the gearbox for manually pushing the wheelchairs these came from. I'm pretty sure that the last two gears are different sizes, with the larger of the two on the output shaft.

If the shaft diameters are the same between the output shaft and the first shaft, I can swap the gears so the larger one is on the first shaft, which will give me some amount of anti-reduction (gain?) within the gearbox itself. If they're not the same ID but I have or can make a collar adapter for the difference, I can still use the gears swapped; just have to lathe out the smaller one to fit.

Then I have just that much less anti-reduction to do from the gearbox to the wheels. If the gears are the same OD/teeth or the larger is already on the first shaft, I'll have to do all the work outside the gearbox.


I've also considered taking the motors off the gearboxes and affixing a timing-type pulley directly to the motor shaft but this would require creating a drive-end plate for the motor that supported the shaft, as right now that bearing is part of the gearbox. This is not that trivial a matter to do, for me.

I would then need a much larger pulley on the wheel itself. I can't recall offhand the motor RPM, but somewhere in the 3000 range, I think. That would be a ratio of about 9:1. The smallest belt pulley I have around here is for a V-groove, and it's around 1.5". So I'd need a 13.5" diameter pulley on the wheel!

I can't recall the way to figure minimum number of teeth I'd need engaged for a timing pulley, but I suspect it'd be at least an inch or two in diameter.

Can't really use chain; at 3000RPM at the motor end that would be a helluva noise.


Basically, at 9:1 reduction, compared to 1:5 anti-reduction, I'm better off sticking with the gearboxes and using bike chain/sprockets for output shaft to wheel transmission. It's not as "efficient" as less stages of changing ratios around would be, and it's heavier, but it is a lot easier to do, with less stuff I have to build from scratch to make it work.



Now, one problem I have is that for the right side wheel, to get power from the motor to the wheel, I need the motor on the right side of the wheel, just like it will be on the left side wheel. But that would be problematic for reasons of safety, clearance, and keeping the motor itself safe from damage. So the motor must go on the left side of the right side wheel.

That leaves the issue of how to get power to it. To use a regular bike hub for it isn't that big a deal, as I can just bolt a sprocket (or weld it) to the left side of the hub. But I will want to use the internally-geared hubs for this later, and those will need the sprocket on the right side of the hub. Meaning I have to get power around the wheel somehow.

Thus, I will probably end up using an extra hub at the rear of the fork, to act as a jackshaft and pass motor power thru to the other side of the wheel. I can simply use a front hub since I don't need to put any freewheels on there, or spoke a wheel to it, and just bolt the sprockets on thru drilled-out spoke holes if they line up right. An adapter plate if they don't. Or weld them on, one on each end.

I just weld on some little dropout tabs to the fork near the U end of it, just clear of the wheel.



For the fork itself, I'm going to need to take some 24" or 26" U-forks, and cut them in half at the stem end. Then weld a tube across there to space them far enough apart for a rear hub to fit in the dropouts up front. But since the internally-geared hubs need dropouts that are slotted to fit them, and I will need enough dropout length to use to adjust chain tension (no derailers), I'll need to remove the original dropouts and put on some from scratch or from BMX bike frames.

Alternately, I can just build the forks from scratch, which would simplify making them significantly, and give me control over every part of their design, as well as make them the same for each side, mirrored. (well, mostly)


Another thing I've been pondering, and that is which way to make the forks--vertical or horizontal.

Horizontal will keep more weight down low, which is very good for a trike. But it means the motor mounted on there will have to have it's weight swung back and forth on the pivot every time I turn, which will act as a pendulum weight and make steering a tad more difficult--it will tend to resist starting to change the wheels direction, and resist stopping that change, too.

Vertical will essentially fix the latter, but will place at least a little more weight up higher. I can still mount the motor itself so that it is centered about the axle, and that will keep most of it's weight low, but the fork will still be higher up and that weight will be above the centerline, giving the trike just that much more susceptibility to tipping in turns, especially if I use the kingpins/pivots up at the top end of the forks.

If I mount the motor vertically on a horizontal fork, it will end up as the best compromise, but it will interfere with the steering pivots and kingpins, unless I move it farther forward, and then the pendulum problem reappears.

Probably I will go with the horizontal fork, and change it if it doesn't work out right.


I've been going back to my old trike research and rereading info I found then but didn't apparently fully comprehend at the time. Now I have seen enough stuff in action and worked with various things in steering, and I understand them better. I think if I had built a trike before, unless I had simply copied someone else's design, I would have ended up with an unsafe or unrideable trike. :( Now I think I know enough to make a passable first shot at it. ;)


I am certain that I got lucky with CrazyBike2, in that it's configuration ended up working fantastically well for something so randomly chosen at each point in the process. I'm fairly good at the by-guess-and-by-gosh process, but it doesn't always work. :roll: The trike needs more thought put into it, and more choices of parts based on design rather than just whatever I have laying around. That said, I think I have a handle on it, and might be able to start building it in a month or so. Less if I'm lucky enough to figure the rest of the design out sooner.

Trike Motor Mount Thoughts

A little redrawing needed. I found the article by Julian Edgar I had been thinking of that explained this stuff, which reminded me of a few things.

The "steering inclination angle" for scrub radius is indeed pointing at the center*line* of the tire, but not the contact patch itself. I still need to have caster (trail) so it needs to point ahead of the contact patch. ;)

I also came up with a couple of possible ways to add the motors to the front wheels, but I am thinking I might want to have shiftable gears, at least two of them, since I end up in stop-and-go traffic often enough to make the power usage horrible, since it will use a lot more current at slower speeds if it's geared high enough for 20MPH.

Apologies for the incoherence of the sketches; I did them while eating dinner since I had the ideas in the middle of that. So they're not pretty. Later they'll be translated into Sketchup if worthwhile.

One issue I have is that i need to get about 5:1 gearing if I use only 24V to drive each motor, because they were originally designed to drive a 10" wheel at 8MPH. To get a 20" wheel up to 20MPH, I need 5 times the output RPM from the motor. On CrazyBike2, that's partly acheived by running it at 36V (now 48V), and partly by the bike drivetrain. Plus, the motor on there runs about 200RPM at 24V IIRC, and these only run about 135RPM or less. So it is a challenge either way, if I use a series wiring setup as the electrical equivalent to a "differential".

One of the ideas uses rear triangles on the front, with the old style one-piece cranks for the triple, and a 5-speed cassette on the back. Only the back gets a derailer, because the triple isn't used for shifting, just as a jackshaft. The left side triangle keeps it's triple. Only a single large ring will be used on the right side's triangle instead of a triple, with a granny ring welded on to the left end of the shaft.

The motor would bolt to a bracket fixed to the triangle in a way that leaves it below the chainstays (for COG reasons) and on the "inside" of whichever side it's on. On the left side wheel it's on the right side of the stays, so that the chainring mounted on the axle hub will be lined up with the granny ring of the triple. The right side wheel will have the motor on the left side of the stays, running to the welded-on granny. The large ring of either side will run to the wheel, shiftable to each of the cassette rings by the derailer. Both derailers would be operated at the same time, by a ganged shifter setup.

Has to be a ganged setup so I can properly adjust each derailer for shifting, while still shifting at as close to the same time as possible. Will also have to shift while not under load, cutting throttle way back during the shift, so that I don't end up being pulled back and forth on the road by the difference in speed while one wheel is shifted but the other is not.


I fully expect this to be too complex to pull off well, so an alternative is to use the regular front fork, and set up the wheelchair motors themselves as if they were the bottom bracket with two rings and a front derailer. This would require putting the U of the fork in front of the wheel instead of behind, and might require putting the righthand motor on the outside of the wheel, which I don't want to do.


Now, I know the reports on the internally-geared hubs under motor power aren't good, but if I used one for each wheel, and ensured no shifting under load and no sudden starts, I might get away with using them. This would make it a LOT simpler to use these wheelchair motors and gearboxes to drive the front wheels. Ganging their shifters would present the only real challenge. Besides actually acquiring two identical ones as part of scrapped bikes, that is. ;)


If I don't use a shiftable transmission, then I can go with a simple chain and ring, but I will probably have to use a two-stage to do it, due to the large ratio required, with the largest ring on the motor, and the smallest on the wheel, with an intermediate jackshaft making the second stage. I could do a 48 to 21 first stage, and another 48 to 21 second stage. Alternately, a 48 to 16 first stage, and 34 or 32 to 16 second stage, to keep stuff a little smaller with a little less chain weight.


Any way I do it, I will need to widen the U forks to accomodate a regular freewheeling cassette, even if I only use one of the rings on it, with no shifter.

The original thought before i realized the ratio needed was just to use a belt and pulleys:


The tank style steering:


More later as I think of it.

ARTOO Concept Sketchups

So now for some concept images, created in Google Sketchup mostly using existing bike parts from things found in their 3D warehouse.

The wheels are 20", for visual scale. The main tube is 2.5" O.D.

The side view looks a little long. I am not sure if it will need to be this long or not yet.

There's no detail to anything yet as I am still working out positions, angles, etc.

The top view makes it easier to see the camber of the wheels, which is 7.2 degrees in the drawing but I don't yet know what it has to be in reality. It just "looked right".

The wheel supports angle back because that is the direction of pressure in a turn and it is also the direction I would want it to angle to during shock absorption if I ever get that far.

Front view shows camber clearly. The green bits are the Razor scooter headstocks.

I intend to have the line thru the headstock it pivots around point directly at the tire contact patch. If I understand how steering should work, that should give no scrubbing of the wheel during a turn, for better traction. I am not *certain*, but I do not think trail matters much in the case of a tadpole trike, based on the way I see it working in my head. Thus, there is no trail on this steering setup.

An iso view.

The steering pivots are behind the wheel pointing forward and outward at the contact patch. It is possible I will have to make it point forward of the patch instead.

Amberwolf's Recumbent Tadpole Ought-One (ARTOO)

Now that it has a smart-ass moniker better than the last bike, lets see about getting the design together. :) Sorry there are not a lot of pics yet, still working out the design ideas in my head.

It's based partly on Lee's most recent trike from The Packrat Workshop, after some conversations with him about what might be best adaptable to the parts I have on hand. So it likely won't have suspension, at least in front, for this version.

It'll be a single-tube main frame, probably made from a 2.5" fencepost I have.

That galvanized post with the mangled right end, within the L of square tubing, is the one.

One possible way it could be configured, but probably won't be:


Depending on length of things I might use this instead:

with the load-wheel tubing cut off, at the far right, and most of the mast up top cut off.



That will go back to a bottom bracket pivot point for any rear suspension. I will probably not have a spring/shock for it by the time I need to ride it, so it will end up with just a solid tube bolted in place of whatever shock I would have used. I still want to build the pivot into it now, though, so it can be much more easily suspended later. :)

The rear triangle will be a modified one off of a 24 bike, probably off the old Roadmaster frame I originally started to use for CrazyBike2's rear end, but swapped out for the much lighter and slightly longer Schwinn frame instead. The main modification will be to make it vertically shorter, by cutting the seat tube down and bending the seatstays to meet it at the much shorter location. Rather like the back end of CB2 already is. This is mainly so that the entire triangle will be "below the deck" of the cargo pods that will run alongside it. Probably a 24" wheel, too, since the best slick tire I have is for that size.


Those pods will be the pods off CB2, mounted on a frame very like the one CB2 has, except that it will all be hanging from the back of the main tube, not connected to the rear triangle. Thus all the cargo pods will be suspended with the rest of the bike frame.

The seat will need to be built from scratch, and will be a lot like the one on CB2, but more form-fitting, if i can bend the tubing this time. I'll be again using tubing off an old bedside potty chair, same as on CB2, since it is small-diameter and extremely strong. The webbing will probably be the same green stuff I used on CB2's seat, simply because I have more of it and it's lasted just fine for more than half a year so far. It'll be tensioned using the same parachute cord lacing I used for CB2.

Like Lee's trike, I'll use tank-style steering, as it's mechanically simple and easy to build. It also doesn't take much space for it's movements, and won't get in the way of getting up and out of it like handlebars would, nor will it get in the way of my leg strokes for pedalling while turning, as can occasionally happen with CB2's bars at extreme turns with my kneecaps. :(

Pedals will be over the main tube and out beyond the front wheel axle, though probably not beyond the whole front wheel. Not completely sure until I finish the 3D sketches of it how the alignment works out.

The front end is where things get different. Because I am going to be forced onto sidewalks sometimes by either traffic or ignorant law-enforcement personnel, I can't make it wider than the sidewalk. Since a number of bike paths have protection poles across them to prevent cars from driving onto them, and those are generally spaced wide enough for wheelchairs, the front end will be no wider than a wheelchair.

Some of the parts I am considering for it:



Each front wheel will have it's own non-hub motor, most likely a wheelchair motor with it's reduction gearbox, with a V-pulley on the output shaft and another V-pulley on the wheel hub. The gearboxes have a tubular indentation in the top of the mounting plate, which happens to be the same as the steering tubes on a couple of the 26" forks I have.

So one idea is to clamp the motor to the steering tube, and setup the pulley on the hub and shaft so that they'll line up just outside the tire's sidewall.

The motor would then stick out to the rear of the wheel, parallel to the ground.

It is just one mounting idea, but one that happens to involve the least modification to the fork to do it. There are some serious disadvantages to it, too.



Then another steering tube is welded to the inside-leg of the fork down nearer to the dropout on the side opposite the pulley, at an angle that gives me whatever camber/caster turns out best for this thing (I still have to work out enough of it to then be able to figure out how to calculate that out).

That steering tube will then go into the headstock off a Razor kick scooter. Those things are meant to fold, so a few inches away from the headtube is a pivot point in the square tubing. That headstock is then bolted thru it's original folding pivot point to the end of a square tube welded at a forward/sideways angle out from the main tube, like a very wide Y. Another pivot point is welded to the headtube above that, which will go at first just to another tube welded to a vertical mast on the main tube.





Later, part of that horizontal tube will probably be replaced with a suspension of some sort, which is why I want the pivot point there now. If I don't end up putting suspension there, I would like to still end up making some sort of four-bar-linkage so I can make this a tilting trike, to improve stability in tighter turns at speed.

As heavy as each wheel will be, that means that the front end should be fairly stable in turns anyway.

To add to that stability, the SLA batteries (probably 4x 12V 17Ah) will be slung underneath the front end and the seat. That should help keep the weight to 1/3 on each wheel of the trike, but I will need to actually measure everything once I get it mostly designed, to make proper placements for things.

There will be cargo pods up front, too; I don't know what their shape is yet as I am not certain what spacing I will have up there.

Behind the seat on it's rear brace will be a vertical post sticking up to windshield level on the average car. A box will be mounted atop that with front, rear, and side lighting appropriate to the direction it faces. There will also be separate lights at the outermost corners of the cargo pods in the rear and the forks up front, for markers, signals, and emergency flashers. I don't yet have a set of lights to put on here, so I will probably be custom-building them. The lenses will likely be made from various bike reflectors glued together, with LED (for any flashing lights) and CFL (for any steady lights) lighting behind them.

Brakes will probably be disk brakes, donated by the very generous AussieJester. I have to fabricate adapters for them, and thus will probably be using some 48-spoke rear hubs I have on some 48-spoke 20-inch rims. The rear hubs are freewheel threaded on the right, but I will flip them over to put that on the left side, and make disc adapters out of something already threaded to that. I might be able to use the bottom bracket tube from an old cottered-crank frame I have, if the threads are the same pitch and the correct handedness. Then weld the tube to plates, face them on the lathe, and drill boltholes to match the disks. Basically they would do the same thing as these.


If I can come up with the cash, I'd rather order a couple of these from Choppers US, as they'd also make mounting the pulleys much easier, too, since they're made for dual-disk, one on each side.

It would also mean I could have both discs on the inside or both on the outside of the wheels, rather than both on the left side, which results in the left wheel's brake on the outside and the right wheel's on the inside. I don't imagine it would make a difference in performance to be the latter way, but it might make fabricating the forks a little harder since they won't be identical nor mirror images.

The catch is those dual-disk hubs are 36-hole, and I really want to use the 48-spoke wheels to help more with the side-loads and weight on this thing.

That's it for the moment, until I can get some pics of parts I have and some 3D sketches done up. Or at least some pencil versions scanned in.

Now, hopefully [i]this[/i] little guy won't get shot in the head when I do the trench run. :roll:

Christmas Bikes For Parts

I wasn't expecting any presents this year, but I ended up with a few. Those NiMH packs in the previous post were a couple, and these two bikes as well. Pardon the stuff on the floor; Hachi was assimilating a bunch of junk mail just before I got home and I'd not had time to clean up the little tiny bits leftover. :-)

The first is a Huffy "Nevada". It's about the same as all the other Huffys I've had or seen, though at least this one has *indexed* lever shifters. Since they are for 3-ring and 6-ring, which I currently have on CrazyBike2, I'll probably move the shifters to CB2 in place of the ones I have (of which the rear one is an 8-speed so doesn't line up with the 6-ring cassette I have now).

It's a 26" wheel bike, with typical steel hubs but aluminum rims. Don't know what spoke type. Brakes are a center pull type I haven't seen before, but appear to work the same as some of the better OTS units I've got. Tires are knobby but not greatly so, and made more in a rounded fashion, so they ride a little better than most of the knobbys I have.

Cargo rack is cheap steel, and would not actually hold much in the way of cargo without wobbling or bending. Well, *relatively* much, given that I expect to be able to haul at least 40 pounds on any bike I ride, preferably up to 100 pounds.

One-piece cranks aren't useful, as I have lots of those. Overall this bike might just stay like it is as an emergency bike, for when experiments in progress on others aren't working or not completed enough to ride.

The other is more useful for parts, and is a Magna "Great Divide".

Like the Huffy it's a department-store 26" hardtail. But unlike the Huffy it has a front suspension fork. It also has square-taper cranks/BB, which is the type I need for jackshafts, and for the easily-changeable chainring sets I'd like to use.

It has grip-shifters, which I like on MTB style bars, but which don't work well for the downturned bars used on CB2, nor are they the safest thing to use with any ebike that has a twistgrip throttle (which I don't use now partly for that reason).

It also uses center-pull brakes, but a different style that is one I have seen, using the same mounting studs that linear side-pull brakes do. These are useful on any bike that has these studs, which many modern bikes, both cheap and high-end, do.

Has the same basic steel hubs and aluminum rims the Huffy does; tires are not as good though.


I have some ideas forming about using the above frame as part of a new version of CrazyBike2, but as a trike. One version of the idea is a tadpole, the other a delta. Since this is a 26" frame, I'm thinking of using a 26" rear wheel, and two 26" wheelchair wheels I currently have on that flatbed trailer right now. They have tubeless foam tires right now, but I'd change those to regular bike tires. Optionally, I could use a pair of 20" wheels meant for single-ended axle mounting. Either way, I'd make this into a full-suspension trike, if it's the tadpole version.

If I do it as a delta, I'd probably only have front suspension, unless I can figure out a way to make the rear wheels independently suspended. And independently driven, rather than a single axle.

It's much easier to build and drive the tadpole, especially as a full suspension. I just have to find all the right parts.

Suspension Not Quite Going According To Plan

Having tried a few variations of the last idea in this post
I ended up breaking the frame with an incredibly stupid attempt, because I tested it without putting any support between the stays:

As you can see, that left me very unhappy.

On the righthand stay is the prior attempt, which was not long enough; I decided to try one a little farther forward and longer, but being farther forward it had zero support from the dropouts and just crushed the tube as soon as I put the suspension together and let the bike's weight on it, and pushed down just a little.

The repair required replacing some of the tubing. Fortunately I had a frame already being parted out with some tubing just larger than what I had to replace, so it could be slipped over the damaged area and welded on.

I cut out the damaged area first, then straightened the dropouts and other stays.

Then I cut off a piece from the other frame large enough to completely cover the removed area plus as much as I could get from it. I left the curved end on because it comes close to matching the curve on the back of the stay to be fixed.

I left the brake stud on there as a way to manipulate the tubing while I did the repair; it will be removed later once I am sure I'm done.

I slipped it over the front of the stay first, then aligned the stays and slipped it over the back end.

so it ends up like this:

Once alignment was certain, with a wheel in the dropouts instead of the triangle above, I welded it in place. It seems as strong as ever, but I am sure it is not quite as good as it used to be.

Now I have a better plan for doing this, based on this idea:
but modified to be adjustable, based on Drunkskunk's seatpost idea:

So that the cut-off part of the seattube will end up rewelded pointing forward, so a shortened seatpost can be clamped in as an adjuster for the ride height.

Now, I still have to work out the chainline issues, as the chain currently wants to pass directly thru the space the pivot BB occupies. I must install something to force it to go around that, yet still shift across it for gear changes.

I have a nylon or teflon cutting board that I may try to cut a strip from that will be used to deflect the chain across, and clamp it to the BB. It will wear, and it will add noise, but it should let me test the feasibility of the suspension while I think up other ways to get the chain around it (eventually redesigning the rear end to eliminate the problem).

550 Miles Coming Up, Motor Changeout

I passed 500 miles sometime in the last week or so I think, and am now nearly at 550. That's the total miles on the whole bike/frame/etc, even though some parts have changed at various points in there. Here's to hoping it lasts at least that amount again, since it is taking far longer to get to the trike than I had expected.


Since I now have bolts that will secure the 4-pole motor in place, and the heat-damaged 2-pole motor gives me a good reason to swap it out, I'm going to try to do it this week, since I only work two days :( and packing/sorting is driving me crazy and depressing me too much to keep at it for more than short bursts before I have to do something else for a bit, then go back to it.

First I have to make a wedge-shaped box or plate to go between the new gearbox and the motor mounting plate on the frame, because the 4-pole motor has an angled top, plus a longer motor cylinder, which combine to mean that even with the cylinder touching the BB between the pedals, and the gearbox as far forward as possible without it's output shaft conflicting with the cranks' rotation, there's still a wedge-shaped gap between the gearbox's top and that mounting plate.

I'll be working on two ideas for making the wedge. One will just be wood to test the angle and see if that is sufficient, and if it holds up to tests without crushing/splintering or working loose from vibration/compression, I will just leave it. The other, if the wood isn't sufficient but does work, will be some steel plate welded into a wedge-shaped box, with reinforcement ridges inside next to the bolts, diagonally (making the interior an octagon).

The chainline shouldn't change more than a couple of millimeters laterally if I measured it correctly, so it should stay tracking fine once I put it under tension and tighten down the motor mounts.

Since it is a faster output gearbox, it'll use a smaller output sprocket on it's shaft, a 21T. This should keep the max output speed still down around something sane for pedalling along with it (since they're still linked, as I have not yet completed that sprocket adapter disc to then hook to the pedal freewheel and try it out).

I should get around the same final speed, but it should be able to handle a LOT more mass and accelerate a lot quicker (at the cost of using more power all the time, because it is 4-pole instead of 2-pole). Theoretically, it makes hill-climbing at speed much easier, but mostly it will make hauling cargo easier (especially if I carry extra batteries on the trailer).

Battery Fairy Now Ships UPS

Of course, that's Uninterrupted Power Supply, not the destructive gorillas in the brown trucks. :-)

The battery fairy came by yesterday, with an old server-sized UPS with both the internal and external battery packs. Unable to sleep due to various things going on in my life right now, I spent the night until dawn or so disassembling the units to get to the batteries and check them out.

The external box just has 4 batteries in it, setup as pairs, two bolt-down wiring tie-in points, and a 100-amp fuse holder to fuse from the next box into this one. The Anderson connector shown on the back is to go to the UPS, then there is another internally-mounted Anderson connector to allow further daisy-chaining of these boxes to the UPS for lenghtened runtime.

It's a nice enough box that I may use it as-is on the trike, if I ever get that far with these batteries (they might not last long enough, as I don't know their age).

They slide out easily enough, with a string-pull on the Anderson connectors to make them easy to disconnect. I'll be leaving those string pulls on just in case. :)

Under a plastic taped-on-with-foam cover are the bolt-on terminals, recessed in each corner of the batteries. Much better than slide-on tab type battery terminals.

The batteries themselves came taped together by a layer of doublesided foam tape between them into 24V "RBC"s, with a 100A fuse bolted between them at one terminal pair, and a 600V/50A Anderson connector at the other.


Those connectors are as useful as the batteries themselves, because it means that now I will have enough of them to make easily disconnected "packs" for the bike. I did not have that option before, and had to bolt on the wires to them each time I mounted or dismounted the batteries from the bike, for fixing it or working on it, or even just to take them off and ride it without motor or batteries for any reason.

All but one pack read at least 23V unloaded; the last read 20V.

Even so they all ran my treadmill motor just fine, even when I put enough load on the shaft to draw about 8 amps (instead of the 1.3A or so it draws unloaded, at 24V).

One battery of the 20V pair is only at 9V, and may have a shorted cell or something. When I put the wheelchair battery charger on this pack, the charger light randomly pulsates at various brightnesses, instead of going off (dark) to show a charging cycle is in progress.

Monitoring the voltage across the low battery shows from 9V to 15V to 17V, while the other is steady at around 15V. So there is almost certainly something wrong with this battery, not likely to be cured by charge cycles.

During charging, maybe 5 minutes in, one of the other packs starts to make very faint bubbling sounds, but loud enough to just barely hear in the quiet room. I had to put my ear up to the side of each battery to figure out which one was doing it. Voltages seem ok on them both, so I'm not sure what's wrong. Current is only 3A max out of the charger, and 5A is the nominal max input current to the battery.

Another pack seemed to take charging normally, with no sounds/etc. After warming up a bit during charge, I unbolted the fuse and Anderson connector from the pack and pulled the two batteries in it apart, so I could read the label/specs of the individual cells. (The outer labels from APC only specify that they're a pack for use in APC stuff, etc, and to use only APC replacements yadda yadda. No numbers).

12V 17Ah by Sacred Sun company, (Shandong Sacredsun Power Sources Industry Co. LTD), max charge current 5.1A. I'm guessing around 13 pounds each, maybe 12.

I'm now letting that pack (as two cells) charge up overnight, then will do the same for the other three.

They're also easier to fit outside my cargo pods. I could even just strap them to the cargo pod-to-bike frame adapter, under the seat, without a battery box, at least for when I'm going to work, since the bike is inside instead of locked up outside where I can't keep an eye on it.

With 8 smaller batteries, of which possibly two might be bad (or will at least fail before the other 6), I have a lot of options.

They can be setup as a series pack for high voltage on that treadmill motor (rated at 120VDC/7000RPM/21A), as a 96V 17Ah pack, at 104 pounds, which would probably not work on *this* bike but should on the trike, and would make it a very powerful long-range vehicle.

They could be setup as a bunch of 24V packs, kept charged and ready to quick-swap out when I get home should I need to go right back out somewhere. If there are any places (like friends' houses) that I have to go where I might need to fully charge up in order to get home, I could leave a pack there on a trickle charger, and simply swap out for the one on the bike when I get there, instead of waiting for what might be several hours (it would also save me the several pounds of charger weight).

36V or 48V packs are also an option, with either one or two packs on the bike, for greater range. I don't know how well the wheelchair motors will hold up under 36V (nominally rated at 24V) but I have tested one of them at that voltage using the three larger 31Ah batteries in series, and it does run, although it is considerably noisier than at 24V.

The treadmill motor is by itself very quiet, but with the alternator fan on it's shaft it is like having a little bitty box fan on high. Moves a lot of air, though, and keeps the motor pretty cool at 24V and 36V. Probably at higher voltages, too, since it's original use at 120V running the treadmill didn't even have a fan on it, just some very minimal vanelike strips on the back of the cast iron pulley/flywheel that came on it's shaft. Those did not move much air at all, even at rated voltage (though they were much quieter). Still, it's a lot quieter than any of the wheelchair motors, and has more raw power potential than they do. Harnessing it's power is more of a challenge, since it has no easy-to-use gearbox built onto it like they do, forcing me to build my own systems for that (like the pulley-then-chain drive I tried it with before I got the wheelchair motors.


Besides the batteries and cabling, there's also a wealth of other EV parts inside the UPS:

More 100A fuses (which I think I'm going to use one of on each battery in case something stupid happens, since it *is* possible to connect batteries together directly in parallel with these Anderson connectors, and if one is fully charged and one is fully discharged, I can imagine some "interesting" things that could happen.

Interesting as in the Chinese curse and as in traditional Chinese fireworks. ;-) I prefer boring to that kind of interesting, and hopefully the un-hole-y kind of boring. (yeah, I can hear your groans from here, just be glad I don't do that a lot more).

Inside the battery box is the 100A fuse on top of this pic, with the internal Andersons to each battery, wired in series for 48V total in this box.

More of the UPS case itself, from the back, just prior to disassembly.

Off comes the outlet and breaker section, since it has these inviting arrows pointing at the screws on it.

Three panel-mount 30A thermal circuit breakers, push-to-reset. They're definitely handy. I think the one I have in the system right now is a 20A.

More Anderson connectors.

The front panel electronics. Not sure I have a use for them yet, but you never know.

The interior, main board, transformers, wiring, and a 120MM fan (24VDC 0.40A). Unknown CFM or sound level; standard 3-pin plug with power, ground, and tach.

Back of the board. It has spots for more MOSFETs and more relays, must be for the next model up or something.

24V 30A SPDT relays. Exactly like the ones used in my ScootNGo controller, except for having twice the SNG's current rating. I will probably use these as contactors for the system, since right now the ignition key only breaks the pot throttle circuit (as specified on the 2QD, which makes it turn off due to "pot fault" detection). That leaves me with no way to totally disconnect power except for disconnecting a battery manually at some point.

The full board. It's quite large, at least one and a half square feet, I'd say.
The four heatsinks each have 5 MOSFETs, IR630P on the front row (can't see the others to tell). Room for 3 more on each heatsink.

Room for more relays, too.

Those MOSFETs are a little hard to read, since they're so lightly printed. None physically looks blown, and at least one in each parallel set must be working, because the gate test works on all 20.

Some very tall caps, too. About 1.5" across, and about 5 inches tall, 75V @ 1500uF. 3 of them.

A whole board full of various kids of caps, chips, transistors, diodes, etc.


Many of the components to build a second full 2QD are on this board, perhaps everything but the LM339 (which I still have another one).