Xtracycle-style Sierra?

I don't know if it's possible to do this with an actual Xtracycle due to it's frame construction, but I am pondering an Xtracycle-like addon (that will do this) to that Schwinn Sierra I fixed up recently, perhaps with a motor assist, perhaps not.

Specifically so that I am not dealing with a longer shiftline and the problems reported with it where shifting can be finicky in one gear or another, I intend to put a regular rear hub with the derailer still on the Schwinn's dropouts, so the original chainline stays as it is, as does the shifter cable. Then there will be a separate sprocket from that hub to the rear wheel, which will be re-laced to a no-dish single-speed wheel to make it stronger for cargo use. (actually I will probably just take a front wheel with a sprocket bolted to it, for simplicity of testing out the idea).

I will probably build the addon frame around an existing rear triangle off of some other bike. I am tempted to use the one off the white Huffy, simply because it is called a "Nevada", which would make this bike a "Sierra-Nevada". ;-)

But that is a silly reason to pick a frame, so I will more likely start with one of the old chromoly tenspeeds I have, whose frames are way too tall for me to use for myself normally. I'd remove the entire rear triangle from the donor frame, but not including it's BB. I would cut down the seatpost from the bottom end, leaving that extra on the BB itself. Then reweld the seatpost and chainstays to a new crosstube from something else. This would all be welded to a subframe that can then bolt to the Schwinn Sierra's rear frame and keep the whole rear end stiff. It would mount in such a way as to leave a clear chain path between the Sierra's rear dropouts and the new rear wheel position, and would be able to slide back and forth for chain tension adjustment and lock in place to hold it once set.

I would like to make some bottom/side rails that let me rest cargo on them (like some Xtracycles do) that are removable, so I do not have to carry them for typical rides, but instead only when I will carry more than normal stuff with me.

Then a top deck to cover the entire space from over the rear wheel to the back of the seat.

I am also considering a more recumbent seat design that would fit down into the gap that could exist between the tire of the new rear triangle and the Sierra's seatpost/seatstays. Then I would move the steering handlebars back to fit in a bushing in the seatpost, and a linkage for remote steering to a stub-bar up in the original stem. This is a very similar arrangement to Justin's (of http://ebike.ca) cross-Canada bike, and inspired by it.

The problem with such a design is that it reduces the cargo I could carry on it, so I would (as Justin did) likely leave the option of pulling off the remote steering and inserting the original seat and post, and riding it just like that. The 'bent seat would stay, as it would make a nice carrier for some cargo. Well, unless the cargo was too large and needed to fit across the full length of the area behind the seatpost.

Just some thoughts for another possible cargo bike, most likely quite short range in nature.

CrazyBike2 Stalled

Not much progress on CB2 itself. Seems like every time I sit down to work on it either I find a serious problem with whatever it was I was about to do to fix the chainline stuff, or something happens to pull me away from it. Or fabricating something turns out to not be possible with the tools I have (or I don't have the skill to do it yet). It's kind of depressing. At least I have the trike design in progress to get excited about. :)

Using that smaller chainring off the Trek is impossible. It would bring the chain itself down to the point it would cut thru the frame. :( Any guide I put on there to route the chain around the frame would probably break under the motor power, probably when I have it heavily loaded and am far away from home. :roll:

To keep the chainline straight on the top where the load is, I have to keep a large chainring on the receiving crankshaft. So it is back to fixing one of the previously destroyed ring sets. Maybe I can mix and match them well enough to double up thinner rings, then use BMX chain for strength. Bolt or weld the ring set together.


Considering welding a threaded section from either a BB cup or a rear hub to the motor shaft's hub end, then putting a freewheel cassete smallest sprockets I can get away with on there. That would get me a freewheel so that I would not be driving the motor when pedalling.

Also considering taking a BB cup and welding it's cup end to the right end of the threaded part of a rear hub. Then welding it's nut end to the face of a steel square-taper crank. The cup would need to be bored out enough to be able to get to the nut and crank threads, so I could still tighten or remove it later.

That would give me a long enough threaded cylinder to do what I originally set out to do for leftside chainrings, which was to put a couple of freewheels on that threaded cylinder with spacers to line up the chains as needed, and allow both motor and pedals to drive the wheel without driving each other.

Problem is, I am not sure that the welding would take the torque, or that the crankshaft itself would take it either, with the load cantilevered out that far. Originally the custom-made cylinder design would have had the motor load still over the actual crankshaft, but both of these would end up out beyond the end of the shaft, putting quite a load on the welds.

So...CB2 is stalled.

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:

Suspension And Motor "Modules" by Gary Payton

This looks like an interesting idea I might be able to adapt to a tadpole trike for front wheel drive.

I could use two of the smaller powerchair motors on there, one on each wheel, perhaps.

I had previously briefly considered two powerchair motors driving the wheels directly from their axles, but that would not have allowed pedalling if the motor system failed or I ran out of power. The above linked design would allow that, as I could put a dog-clutch (or freewheel) in one of the transfer pulleys, which could use either belt or chain.

Also, the motors directly driving the wheels would not go very fast unless I overvolted to perhaps 60-72V, given the wheel size and original motor/gearbox speed. I'd rather not have to carry *that* many batteries. At original voltage, they're meant to go around 4MPH with 10" wheels. So the 20" wheels I want to use on the front would still be pretty slow, less than half the max allowable speed on ebikes. I'd like to be *able* to go 20MPH, even if I don't do it much.


Of course, I found this idea via the V Is For Voltage forum *after* I started sketching up some ideas for the suspension and frame, and setting my brain on the search for a workable geometry with stuff I already have laying around. ;)

So now I am going to see if I can reprogram the "offline mental search" to figure out how to make these modules instead, as they would simplify the frame and steering setups. Plus, I would have front wheel drive with electric, and could leave the rear wheel drive as pedal-only, reducing the stress on that wheel, "spreading the load" as it were. Simplifies the chainline and drivetrain integration, too, and keeps all three drivetrains independent, for multiple redundancy.

Mechanical Repairs Still Underway

First up is a wheel relacing, to replace the badly damaged (destroyed, really) wheel currently on CB2. It's a standard wheel build, except that it is using thicker stainless ones donated to me that are for a wheelchair wheel.

It required a bit of creative relacing that may affect wheel strength as a whole, as these spokes are for a 540 rim, where mine is a 507, I think. I had to install them as crossed pairs where normally they'd be parallel pairs, in the typical 2-cross pattern, so that they would not be so long as to poke thru the tube. ;)

It still gives parallel pairs, just not the same ones as the originals--basically works out as if you went backwards for lacing, going *across* the hub instead of out from it. If that makes sense.

The rim and hub were from the previous CB2 rear wheel, which had a bent axle and a slightly bent rim. I fixed the rim with some working of tension on the original spokes and rebending of the rim, and then I used the axle and bearings from the rear wheel of the Magna 26" I just got as a parts bike a few posts back. I used the Shimano 6-speed cassette from the other (Huffy) parts bike, as it has the shifting-ease type edges to teeth and whatnot, where the Falcon 6-speed cassette on the Magna is all flat edges and plain teeth.

I still have to pull the tire/tube/protection strip off the damaged wheel and put it on this one.


While I was at it, I also decided to do something about having to pedal too fast for comfort or to be able to assist the motor, with the motor at full speed, due to the nearly 1:1 pedal to drivetrain system. I swapped out the single-ring crank I had on the front, and installed the 3-ring from the Magna, which gives me the outer large ring that is one and a half full chain links larger than the single (which also gives me the ability to make a properly tensioned chain, instead of one with a lot of sag).

However, this larger ring is leftward just far enough to cause interference with the motor chain. So I have to move the motor chain leftward, too. The only way to do that is to move the receiver rings on the jackshaft leftward, so I pulled the slightly longer BB axle (crankshaft) off the Magna and replaced the one already on CB2's jackshaft with it. That moves the whole receiver ring set leftward about 1 cm or so.

Then I had to take off the motor's drive ring hub, so I can install spacers on the shaft that push it leftward the same amount. I have not yet done this part yet, as I was too worn out by then.

Once that's done, I can reassemble the drivetrain and have spacing that should allow all the chains to clear each other and remain taut, and in line, removing one more problem that has plagued me since the beginning in one fashion or another. I'm apparently terrible at making good chainlines. :-(


Then I have to look into one more problem:

The last time I started doing a chainline test before the chainline modifications, using the motor to drive the chains at a slow speed so I could watch them pass and move, I heard a clicking noise, and whenever I heard it, the motors' gearbox output shaft stopped for an instant.

It is possible that there is something wrong in the gearbox and something is slipping, but I doubt it as there is no sign of it in other noises I would expect to hear from a wear problem like that, and there is no problem at all when there is no load.

However, it does seem possible that the coupler between motor and gearbox could be at fault. It is made so that both the gearbox and the motor have shafts that are slotted all the way thru, in the center, for about 1/4" or deeper. Into these slots fit a steel tab about 1.5" or so long, which fit together to form a + sign. They are cast into a rubber disc, which is itself enclosed in a pair of metal "cups" with a hole in the center just large enough for the shafts to fit thru from each side.

This makes a flexible coupler that can transmit power but isolate vibration and shocks from the motor shaft, but it is possible for this coupler to fail. I have not yet taken off the motor to examine the coupler's current condition, but I suspect I will find enough wear or damage to cause a problem, probably caused by that last disaster which I am repairing. It did not show a problem in the inital tests of the motor with the Curtis, but all I did was some "bench tests" and then some riding around the block slowly.

If the coupler is bad, I do have another one somewhere around here, if I can find it. I might be able to make one, too, as it is a simple construction.



Again, while I am at it, I also intend to add a fourth battery to the system, which for now will be clamped down inside the rightside rear cargo pod, at the front inside corner. Later when I have more time, I will try moving it plus the third (rearmost center area) battery up to the front in that dual-battery case over the top tube just behind the front headstock.

That will give me 48V. I don't need the speed this could give, but it will mean I don't have to use full travel on the throttle pot to get my original full speed (simplifying setting up the new throttle pot and arm lever), and can "lock out" the higher throttle speeds with a physical adjustment or set screw.

It will also give me more range, since I can use higher voltage to lower the current draw from the batteries for the same power output, decreasing the Peukert effect on them, as well as the additional power from simply having one more battery.


One more benefit is that it will allow me to install both 24V chargers on the bike for opportunity charging, each one wired across two of the 4 x 12V series 48V pack.


Yet another benefit is that I will no longer need the laptop adapter wired in series with the CFL/battery hookup just to start them, so I can leave it off if I choose, or leave it on for even brighter lights.

As bright as the taillight already is, I think I will have to wire the laptop adapter only to the headlight, and take it off the taillight.

Blown MOSFETs Due To Chain Jam, Possible BMS Arrives for Li-Ion Pack

I have been having balanced karma of late--every time something really good happens, something equally bad compensates.

Yesterday on the way home from work the bike's rear chain (regular bike drivetrain part) somehow derailed and got tangled up, which actually pulled the entire right end of the rear axle and the derailer bolted to it off the dropouts and bent the rim up against the chainstay on the other side (the left end stayed bolted in), and then everything jammed and both bottom-leg MOSFETs blew.

The power meter registered over 3500 watts peak, 153 amps peak, which is a more than any of it is rated for--the MOSFETs I installed in my 2QD are only rated at 80A continuous, and can handle ~150A for *maybe* a second absolute max, with sufficient cooling (which they don't have in my setup, by any means). So it's no surprise they blew up.

All that only took about half a second as I was accelerating away from an intersection, crossing two lanes to get to a left turn I have to make to get home without going down a very busy stretch of road.

Then I had to drag the bike across the rest of the lane (while cars that weren't yet coming when this all started kept trying to go around me instead of letting me get out of their way!), up onto the concrete median, and spend an HOUR with traffic roaring by me, while untangling the chain enough to get the wheel off, unbend the rim and true it enough to get it able to roll. Then I had to take out around 6" of chain due to bent and broken links, and set it up to run only in lower gear in front since it was now too short for the big ring. Plus I had to take the motor chain off, since my pedals are linked to it and it is nigh impossible to pedal the bike without the motor running otherwise.

After that it was a heck of a ride home, at about 9MPH, which is just above the unstable speed of the bike, and I was totally worn out when I got home (and then had to go to a different job as handyman for someone else).

I didn't have the camera with me to take pics of the chain/etc, but wow, it was awful looking. It looked like someone had hit my rear wheel from behind and then stepped on it sideways, but it was just from being yanked so hard by the chain as it tangled.

The frame and dropouts all appear intact, but the wheel was seriously messed up. I will need to take it completely apart, restraighten the rim, and then re-lace it to get it back to anything close to really true.

The derailer cage was slightly bent but not badly, but the bolt that secures it to the little shaped nut that recesses into the dropout behind the axle had sheared thru as it was all pulled out. I am just lucky that I carry spare nuts/bolts in the toolkit, one of which happens to be the same thread pitch and diameter as that bolt--it is a bolt from a rackmount kit--it's so long that it prevents use of the highest (smallest) sprocket on the rear cassette, but as I had to pedal with no assist there was no way I was going to be shifting up that high anyway.

I guess the good news is that I *could* fix the problem on the road well enough to get home.


Here's some pics of the controller with toasty MOSFETs, before repair. I still haven't had time to go back and fix it yet; just replacing the MOSFETs and gate resistors (whcih also burned open as they are supposed to) didn't fix it. I'm too tired to try more now, after another day of work. Tomorrow and the next day I have to go help do a roof and some other things, so I won't be able to do it then, either. Fri and Sat I'm working again, so I don't know when I will find the time to finish troubleshooting it. Maybe Sunday. Should be easy, when I have time and am not too worn out to concentrate. (writing this post has taken several tries).

A close up of the damaged area. The discoloration around the screw on one MOSFET is actually the melted remains of the plastic insulator ring...it's still not shorted to the heatsink, but that insulator is totally destroyed from the heat.




This blown LiFePO4 BMS (sent by an Endless Sphere forum member) arrived today:

All that is known about it's problem is that a puff of magic smoke escaped from it somewhere, but not specifically where. With luck it's the MOSFETs, as those I have around here already.

Once I find and fix the blown part(s), then if I can figure out how to change it's HVC and LVC voltages to match those of my Li-Ion cells, I can use it as a BMS for my custom-built pack.

First, I just need to invent a time-machine that gives me extra time to do everything and still get enough rest....

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).

Adding Rear Suspension to CrazyBike2

I've got several options for doing this, and this is just the first attempt, doing it the "easy way", that lets me revert back to the original at any point, without cutting into the original rear triangle. There are certainly better ways of doing it, but because of the cargo pods, they all require severe modification of the whole rear end that would preclude going back if it doesn't work out.

*This* method allows me to even undo it when I'm on the road, if something breaks unfixably on a longer test trip, though that would be pretty annoying and take at least an hour to do.

It starts with the 24" rear triangle originally slated for the unfinished ReCycle, and bolts it's crankshaft/BB to the dropouts of the CrazyBike2's rear triangle, in place of the wheel. The wheel now goes into the new triangle.

Then a shock with coil-over spring, origin unknown but possibly motorcross bike, bolts to the top of the new rear triangle, pointing forward to align with the top of the original rear triangle/toptube to keep all the pushing forces along a strong line. Below is a simple example of how it might work, bearing in mind that CB2's rear triangle is much less tall than the bike frame on the right.

This adds about a foot to the length of the bike, and about 15 pounds (so much for making it lighter) but it appears to be the easiest first try.

First up is finding a way to compress the spring enough to get a large plate on the shock to hold it in. Neither of these thrift store finds had that plate; it was probably part of the vehicle they came from.

I didn't have a large enough washer or other plate just laying around, but I did have a strong steel tile-cutting blade, too worn to cut anymore but still strong, so that has become the first temporary spring-retention plate. It's not very thick, so I suspect it won't survive all that long in real use, but it will allow me to perform some tests without manufacturing something for a shock I might not even end up using.

So I zip-tied the spring on each side and carefully compressed it just enough to be able to assemble the shock, always keeping everything parallel to my body so nothing could hit me if the zip ties broke. I also made sure none of the dogs could get into the room I was in, so they wouldn't be in danger--they tend to show up at the worst possible time if something is going wrong (before I even start cursing ;-) )

Once compressed suitably, it was easy to screw it all together, then tighten the jam nut against the pivot ring's nut so it can't work it's way loose later.

Next up was a simple way to mount it to the rear triangle for a test:

...a couple of pieces of 1/4" plate steel from a big old desk chair, from the L bracket that holds the seat back to the base, spot welded to the rear triangle at it's strongest point where the stays meet the seat tube. I can easily cut them off and move them elsewhere should the need arise (and it turns out it does, later in the post).

First bolted to the shock to keep them lined up, then clamped in place to the tube.

Then spot welded at each corner.

That's the basic alignment, and approximate position under load, at a guess.

It sticks up a lot more than I would like, so even with the wheel out of the way, it'll be too far up to lay cargo across the pods. :-(

It would be perfect if it were like this:

But that's only prior to loading, with the handy-dandy adjustable-ride-height mechanism.
The front mounting point for the shock is adjustable, to give me about two inches of adjust range, for altering rear end height when loaded if it is necessary. I did this by cutting a strong hard steel plate off the bottom of that same desk chair as above to weld to the square-tubing that supports the cargo pods and seat, as that is the strongest point on this section of the bike.

The silver part is the steering tube from a discarded Razor kick scooter, along with it's "fork". I bored a hole in the plate large enough for the tube to fit thru, with the "fork" end pointing rearwards. I threaded the top nut for the tube on it's "rear" end, behind the plate, and the locknut on the "front" end in front of the plate. Those are what let me adjust it's length, and secure it to the bike. It will not be easily adjustable on the road, as it is under the seat; it is only there so I can change the ride height if I anticipate needing to do so before a particular trip.


The preloading will be done by a tub-balancing-support cable off an old washing machine which will restrict how far the bike can pop back up after I get off of it, which will normally be sagging loose during the ride, so it will only ever have a load on it when it's not being ridden. It's main purpose is to keep the chain from ever having to rub on the frame, and so I can see what the bike is like when I am not on it, plus not having to climb up so high onto the seat. :) The shock itself doesn't have a preload method built in.


This is what the whole bike looks like now, without the preload yet, so it's a lot higher off the ground that it will be.

The spring compresses about 2/3 of it's length with me on it, leaving a bit for bumps and whatnot. If I have much cargo in the pods, it will compress most of the rest of the way, unfortunately, requiring a different leverage method for the spring to use it properly. I'm mostly doing it this way now so I can easily undo it, and because this method is easy to build and test.

This is the rear view, again no preload yet.


A closer view partly from the top/rear, where you can see the extra derailer used only for it's tensioner, at the original dropouts. It's there solely to take up the slack as the triangle moves back down, and provide enough extra chain that I don't need to worry about the actual rear derailer jamming due to chain overtension when I'm on big ring front plus big ring rear on the occasions that must happen.


Now, chainlines I'm still working out, so stuff may change as I do this. In theory with the spring preloaded by cable, the chain should pass normally thru both triangles to the rear wheel. That might not work perfectly thru the gear range at the back, so I might need to add a guide wheel to get around the stays. Hope not, but....

A close up shot of the ride height adjuster.


In first testing, I already had a problem (of course). The steel plate the whole thing goes thru under the seat is great when pushing against it, but apparently not in pulling.

I didn't take a pic of it, but when I sat on the seat and started bouncing up and down to see what would happen (before I put this thing on the road), at full compression the angle of the shock is just above and down onto the front pivot point. That forced the pivot to pull on the plate rather than push against it, and the whole assembly sort of folded down into the empty original rear triangle. Easy enough to bend back up once I got enough leverage, but it certainly suprised me (and shouldn't have).

So I'll need to do some rethinking on this. I have a 1/4" steel bar that I put under the pivot point across the square tubing for the cargo rails, and this prevented it from happening again, but I don't want to add essentially another pound just for that--plus eventually that might bend, too. A thicker plate for the pivot to bolt into would help, too, but again, it's just more weight. There should be a better solution.

I could move the rear pivot point downward closer to the BB, so it is always pushing upward against that plate, or even better against a pivot point that is part of the cargo pod rails. That would actually counter the weight of cargo in the pods pushing down on them, and if the pivot point joins the rails horizontally it will also stiffen that part of the frame.

Chainline currently does not come out right, so having to rework this is actually helpful. I might wind up putting a large sprocket (to reduce noise) on a jackshaft in front of the rear wheel, between the cargo pods, to keep the top of the chainline clear of both sets of stays even during pivoting.


Another idea DrunkSkunk from the Endless Sphere forums had is to use a seatpost in the seat tube, and attach the rear pivot point to *that* instead of my contraption from the Razor/chair up front. Then I could move the seat post up and down for ride height adjustment, and if I use a quick-release seatpost clamp, that'd be very easy to adjust.

The same problem I have with the first arrangement comes in here, though, where the shock is in the way of laying cargo across the pods--something I would like to be able to do, and could not do with the tire there.

If I move the front pivot point to somewhere within the dropout area of the original rear triangle, then I can have both the new adjustment method and be able to use the top of the pods for cargo, too. I just have to put the bottom connection point on in a way that won't interfere with putting the bike back together the way it was, if none of this works out.

It'd look something like this, I think:

where purple is the original frame, brown is the load-bearing cargo rails, orange is the new triangle, gray is the seatpost, and red/black is the shock and spring.

Motor Rips Loose From Mounting Plate

(Much delayed posting due to holidaze and circumstances; was started thanksgiving night but not finished till the 28th)

Last week, on the way up toward Arrowhead along the canal, about 3 miles from home, the motor mounting plate gave way along the only rightside mounting bolt it had.

It looks much worse in person than I could capture on camera. The largest hole in it on the right rear of the plate is for the old motor's clutch lever to pass thru, and that weakened the plate enough in that area that the hole for the rightside mounting bolt of the new motor, right next to it and partly intersecting it, finally expanded and let the bolt pass thru it.

It took a small chunk of the plate out with it. This was during uphill travel on one of the under-road tunnels on the canal path; they're pretty steep. Not sure of the grade, but steeper than I can pedal up from a stop on my other unpowered bike, the DayGlo Avenger (the upright aluminum bike), without hurting my knees pretty badly even in the very lowest gear, and even that only at just enough speed to stay barely upright (if wobbly); perhaps 1-2MPH.

I didn't have any thicker steel plate, so I just cut another plate of the same material and same shape to weld to the existing one. First I had to hammer and bend the other plate back mostly flat, then I clamped them together, welded one edge (where it joins the frame), then clamped along the flat portion of the plates and welded thru the various holes in the plates (mounting screwholes from whatever they originally came off of) to the plate underneath, to join them more thoroughly. Not as good as a single thickness, most likely, but good enough for this, I hope. Sorry there aren't any pics of this process; again I didn't think to do it until too late.

After welding them, I did a lot of comparing, holding, marking, placing, and test-fitting of potential chainlines before I drilled any new holes, and before cutting the new slot for the chain to pass thru on the left edge of the plate (it's only major weak point now that there will not be slotted holes nor clutch lever hole).

Eventually I decided to do two things differently than before. First, to move the pedal crank chainring to the *right* side of it's spider, since it is a bolt-on to a flat plate.

This moves the pedal chainline right far enough to completely clear the motor chainline, even if I move the motor chainline more right as well. Then I did that, too, by flipping the hub over, cutting off more of the hub the same way I did it before (hacksaw while spinning it on lathe), and using the removed parts as spacers on the left.

This also allows me to center the motor better between the cranks, and it straightens the motor's chainline--part of the problem I had with it coming off (besides flex from the motor plate prior to failure) was that the chain had to be super-tight due to the chainline passing from left at front to nearly 1/4" out of line at rear, with no guide or jockey wheels to keep it lined up where it met the bottom of the receiver sprocket. So under the right circumstances (left turns with a lot of tilt, especially on bumpy roads or rough intersections, etc), it would come off, and sometimes tangle.

Now that won't happen, as the motor's chainline is as close to straight as I can see, as is the pedal chainline. The pedal chainline doesn't even need the tensioner/guide wheel anymore; even under bouncy conditions it stays on, so far, despite still being about 1/2 link too long.

I left the plate to bolt the wheel onto in case I have problems on the road; the wheel and bolt is in my toolkit.

While I was at it, I also welded up some battery retainer strips, just to give them some guide at the bottom, so I don't have to keep using the wood blocks (which deform over time and have to be readjusted) to keep the batteries from shifting around. For the front battery, I just used the bottom tray from a small standard computer UPS (the kind that uses a 7Ah battery), and cut a piece just long enough to tack weld onto the bike frame and still keep the bottom of the battery from moving side to side.

I cut a small slit for the hose clamp that secures the batteries to pass thru, for more clearance to the chain. No rubbing problems, even in a hard right turn. It does rub if the bike is tilted far enough to lift the rear wheel off the ground, using the right cargo pod as a "stand", but that's not relevant to riding it.

For the rear battery, which was the most problematic on the road, I took the two triangular strips left from cutting the new motor mount plate, and notched them to fit the frame and be out of the way of the motor bolts.

Then spot-welded to the frame and motor plate (as this also stiffens the motor plate some), and can now clamp the battery down without worries of it moving. Due to chain clearance, the clamp only goes around the rightside plate, but it is very secure and doesn't shift around even with that.

A quick shot of the PDA used as a bike computer, showing the readings at the time.

22MPH was unpowered gliding down into the tunnel that I had to walk the bike back out of due to the motor plate breakage. Usually (in daylight when I can see in the tunnel and it's entrances better) I can keep gliding until I am most of the way back up the other side, as long as there is no other traffic (normally there is not) or anyone sleeping in the tunnel with a cart full of their belongings (this happens more than encountering other traffic), and then I can engage the motor in a low gear and continue up the rest of the way.

This time it didn't work out like that, because when I engaged the motor, almost instantly the motor pulled out of the plate on the right side, which allowed it to be pulled left and back by chain tension, getting in the way of even the pedal chainline, which made me just stop right there, and set the parking brake lever (taken from the scooter) on the left, to the rear wheel. Then I saw what had happened, and just ended up walking the bike the rest of the way uphill, then walked it home via the surface paths.


Some new full-bike pics, including the headlight/taillight. First is the room light (same 15W/60W CFL that's in the HL/TL) and camera flash.

Next is just the room light, flash, and HL/TL.

Just the HL/TL

Just the room light, HL/TL. No flash.

Just the room light, no flash or HL/TL.


I've now gone another 31 miles, for 905 total, and the only thing I had to change (at 882 miles) was to weld the longer piece of hub that I'd cut off and used as a spacer, to the end of the hub it now sits against.

This is because the little pin that rests in the groove of both the hub and gearbox axle isn't long enough to totally fill the space from one to the other, and apparently can work it's way loose. The original one *was* long enough, but I managed to misplace it during my original modification of the hub, and had to make a new one; for whatever reason I no longer remember, I did not make it the same length. Now it's welded, *and* has a hardened torx-head bolt threaded into the groove for the rest of the length, to ensure full contact and power transfer between the axle and hub.

I was very lucky that it failed where it did, less than 1/4 mile from a friend with a welder and the large 19mm wrench it takes to undo that locknut, or I would not have made it home in any reasonable time that night--the motor couldn't transfer any torque to the drivetrain, and I could not have gotten the nut off to put the pin back in place (the washers block the pin from coming out, and thus anything I have from going in!). So my thanks to him for letting me barge in after turkey-day dinner and use his tools!