What mid-motor might fit?

[amberwolf]

However, I really need to figure out configuring the CAv3 so that the throttle isn't so touchy, I need a much lower 'gain', so it's so much power with just a tiny bit of throttle. Likewise on my cadence PAS, first time using one, and it just seems to go to full throttle when it turns on, not just a little bit of help. Any recommendations on that?

I use cadence-controlled speed on the SB Cruiser, and it works well. I don't think I've changed anything in that regard since creating the settings I've attached to this post back in 2019. I'd recommend looking at these settings using the CA setup program from grin, and comparing them to what you use to see what you might be able to copy over and check out on your system. (directly using all of my setup is unlikely to work on yours as our setups are different).

 

[Drizzt321]

I use cadence-controlled speed on the SB Cruiser, and it works well. I don't think I've changed anything in that regard since creating the settings I've attached to this post back in 2019. I'd recommend looking at these settings using the CA setup program from grin, and comparing them to what you use to see what you might be able to copy over and check out on your system. (directly using all of my setup is unlikely to work on yours as our setups are different).

Thanks. I actually lost my programming cable, I have another one I just ordered. Hopefully here by Wed, Thur latest.

The small sprocket on the jack shaft is great. The motor runs at decent RPMs, but the actually axle shafts are moving a bit slower. I think it's a lot better, although of course I'd still love to have a somewhat lower motor power at lower throttle.

Video! 20250810_192233.MP4

I do have to get a chain tensioner on the motor<->jackshaft sprocket. Fortunately I put in some M5 threaded holes in the motor mount, just need to get some bolts for it. Time to go get a few different size bolts, washers, nuts.

 

[amberwolf]

Thanks. I actually lost my programming cable,

The good news is you don't need one to look thru my settings with the program, and then to compare them to yours--you can open any of the .hex setup files in the program without being connected to the CA. Then you can go thru the relevant menus in the setup on your CA itself to compare, and play around. When you start to get close to something usable, you can then save that whole configuration on the computer via the cable once it arrives.

 

[Drizzt321]

The good news is you don't need one to look thru my settings with the program, and then to compare them to yours--you can open any of the .hex setup files in the program without being connected to the CA. Then you can go thru the relevant menus in the setup on your CA itself to compare, and play around. When you start to get close to something usable, you can then save that whole configuration on the computer via the cable once it arrives.

I'm just gonna wait for the cable, since it's SO much easier to look at it via the programmer. Plus, my CA is older, has 3.0 1 firmware on it, and looks like some of the settings have been tweaked/changed. Might just work out I want without much effort with 3.1.

Now to run all the wiring/etc semi-neatly, and safely. And in a way that's easy enough to remove some parts, since I'm putting it on the roof of my car for transportation. Going to look crazy. From wheel on a normal roof rack bike carrier, except way forward sticking out over the windshield, and rear wheels 9n canoe carrier blocks, hopefully far enough forward to let me open the rear hatch to access it. And then ratchets going back to front and front to back to the roof rack crossbars.

Plus there's going to be a 27' flag pole with lights all up it, a PVC 'holster' for the light up cane I made,and LEDs along various spots. I suspect I'm just going to need to end up zip tying some to the frame parts I'm going to do. Need to do some kind of screw down holders and glue for the rest. Might need to do it AT the Burn I'm running so far behind. Hm. Might get lazy and just get hold down wire staples. Need to get some small screws, make sure I don't go down through the 1/2" ply of the box. Yeah. Lazy. I like that. Especially since my 3D printer has been cantankerous.

 

[amberwolf]

the light up cane I made

I'd like to see that, too.

My cane holder on SB Cruiser and the old CrazyBike2 is a "wet floor" sign holder.

To use it horizontally, I wrapped a rag around the bottom of the cane and ziptied it on there; later siliconing that in place, to create a friction fit to hold the cane in while riding but make it very easy to still pull it out when I get off the trike to walk around. Original plan was to make a rubber foam "cork" around it but the rag worked fine, so....





Used to be like this


and before that it was like this

 

[Drizzt321]

@amberwolf Mine's a 3" (I think) black PVC with one of those drain mesh glued into the bottom. Held on by pipe clamps around it (through some thin slots I cut out of the bottom of some wood). Then the wood backbone is glued on (wood glue) to the plywood box, with a few screws from the inside for a little extra support just in case. Then some bungie to hold the cane down by the handle or wrapped around the tube.

I'll have to get some pictures when I'm there with everything put together. At this point, I'm going to be finishing off building part of it (mostly the lighting and final wiring) while I'm there. *shrug* About usual for things.

 

[amberwolf]

@amberwolf Mine's a 3" (I think) black PVC with one of those drain mesh glued into the bottom.

First time I set mine up, vertically, I didn't think about the drain problem...after the first rain filled it up to the first wall-screw-mounting-hole it has molded into it, about a third of the way up? I drilled a tiny hole in the bottom and that was enough (not like it rains here much). Once I moved it horizontal it was no longer an issue. (it's a lot easier to pull out horizontally before I get off the trike, to use it to help me get up).

Held on by pipe clamps around it (through some thin slots I cut out of the bottom of some wood). Then the wood backbone is glued on (wood glue) to the plywood box, with a few screws from the inside for a little extra support just in case. Then some bungie to hold the cane down by the handle or wrapped around the tube.

I had to give up on bungees after having so many of them sunrot in just weeks (less for crappy ones), in the az sun. :/

I'll have to get some pictures when I'm there with everything put together. At this point, I'm going to be finishing off building part of it (mostly the lighting and final wiring) while I'm there. *shrug* About usual for things.

I wish I had the energy these days to work as fast as you do.

Are you going to have a music system on it too? (seems like a lot of the bikes/trikes I've seen posted from BM have them, along with all sorts of lighting). I use an old Vizio soundbar with BT to my phone cuz it runs off 16v and that's what my lighting pack is (when full). I use it to listen to my compositions-in-progress when on my way to / from work or the store, whenever I've got a new one going that I'm still working out details on. (being right behind my head it doesn't have to even be loud enough to be heard by anyone else around me while i'm riding)

 

[Drizzt321]

Having the mesh at the bottom is more about dust for me, but yeah.

For the bungies, well, it's not out there so much that it matters. But yeah, in the sun/heat it'd degrade fairly quickly. Consider using a pull latch with some something like some nylon webbing? That probably could last pretty well, and has a slight bit of give so that it'll tighten up well.

Heh, this isn't working fast. If I had some kind of real metal shop capabilities (a decent 90 deg cutter, small welder, more accurate means of drilling holes) I'd probably have gotten to this point a month ago. It's been soooo slow to me. Waiting for this part, waiting for SendCutSend, waiting for this, waiting for that. It's like I get stuff in, and then have to wait 4-7 days for the next set of parts/things to try. The iteration/testing of things has been so slow. If only I had planned a bit better in regards to the mid-motor. If that hadn't happened, or I had planned for it right away, I'd probably have been done with the core of the trike 3-6 weeks ago, and have finished all work on the box on the back, and have been sipping some wine and hanging out with friends all this past weekend instead of futzing and FINALLY getting the motor & pedals to work well.

No, I'm not going to do any speakers. I've done that before, there's plenty enough music going on around elsewhere all over the place. Maybe some time. I do have an OK pair of cheap speakers and small 12v amp I could use. But then I need a music source and all.

I actually have a separate lighting battery pack for the lighting. That way I can pull it out and charge it when i get home, even during the day, and still have the battery for the bike. I went a little bonkers on the battery pack when I first got it some years ago (doesn't see a lot of use, so still low cycle counts). It's a 16Ah, so only need to recharge once or twice while there. Usually. We'll see this year, with all the dust dunes, might be hitting it more. Usually it's a front hub, so to get my prior upright trikes through them, was always a pain and I had to really pedal. Given it's fairly low geared (motor -> rear axles), I might not need to pedal much. Plus it still has 3 front speeds for me to change, if I need.

What's nice is the sprockets for the motor drive parts are all keyed sprockets, so I'm not worried about slipping with high power. Now I just need to worry about if that's going to drive me through the dust piles as well as I'm hoping it will... Worst case I get off and push it through *shrug* They aren't usually _that_ big, a dozen feet across generally, or big enough for me to easily see and go around them.

 

[Drizzt321]

So post-mortem:

Issue: With the jackshaft,even with some amount of chain tensioners/guides, it was tricky to get things right to get the motor & pedals working without regularly hopping off the sprockets. This was further hampered by the fact that those extension arms were actually _angled_ inwards, slightly, because A) the rear arms/dropouts were angled and B) there was a small difference in width between the dropouts width and the bike-to-trike conversion bolt points. And also the motor mount arms ended up being sorta partially not entirely straight along the chain path, although the motor was reasonably well straight along the chain path. Except that the tensioners I used were mounted (through the helpful M5 threaded holes I built in) to the motor mount arms.

Advice: So have some way to adjust forward/back up to 1/2" in total, overall, to at least get the chain links from the motor to the jackshaft well tensioned without needing more than a chain guide, perhaps, rather than a chain guide + tensioner sprocket thing like I needed (and fortunately brought just in case). Or plan better to have a proper spring chain tensioner in the path and installed quite straight to the chain path.


Issue: Also, the solid metal spacer on the one axle side was important to keep distance, not just to 'protect' the axle from dust and stuff. I had made a TPU cover for the freewheel on that side, and it extended out over the axle, and so the length of the metal spacer was a touch long, so I made a TPU cover to replace it. I now realize it kept the axle from shifting outwards slightly, and thus causing the nylon joiner (between the freewheel on one side, and the 7-speed on the other) and so due to the motor having enough force on that axle, it would partially spin/damaged the nylon joiner on the 7-speed side. So now need a new one.

Advice: Understand what all the parts do, before you decided to change them out for something without similar mechanical properties.


Issue: The very low gearing has great torque, but I think slightly higher gearing, maybe another 5-7 teeth on the jackshaft sprocket would probably have been good, allowing the motor to run at somewhat less throttle for similar speeds, and thus using a bit less power. Although some of it was just the absolutely HORRIFIC surface conditions this year. First very deep powder dust piles everywhere, and then the rains and people coming in/driving which started to tear up the road surface causing bad to horrific bumps & ruts and such everywhere. So probably was going to use more power regardless. The good news, with my larger house battery (280Ah @12v) I didn't really mind charging up 10-12Ah even in the afternoon/evening when my solar (400W @12v total) wasn't producing much or at all.

Advice: Have a chance to actually USE whatever your build is, even if not in exactly the same surfaces, and perhaps find some torque vs rotation speed calculations to decide what the right ratio is. I just didn't have the time to do so.


Issue: Probably low(ish) pressure 3.5-4" fat wheels, at least on the rear, and larger diameter (24"/26" instead of 20") would have been MUCH better. Partially shock absorbing, partially better grip when it was muddy/slipper. I had 20" 2.125" tires on. However, it would have raised up the seat a lot, so I would have had to have spacers to get the extenders much more horizontal so I could actually step over and sit in the seat. So anyone doing any kind of extenders, really consider seat height before you lock in your design, because if you keep it at the angle of the rear mount arms, you'll end up with a much higher seat.

Advice: Consider well the surface you will be riding on, if you get freak weather what might happen, and don't be afraid to learn to re-lace your wheels to larger and/or wider rims, as well as if doing something wacky that might change geometries, be careful of changing height to ground or the like too much.


Issue: And probably last... consider much stronger rims & spokes, especially if you are going to have a lot of weight like someone sitting on the box on top. The last evening of the rains, there was a light right, not enough to be truly muddy, but enough to make the top surface slippery. I was going along, my partner on the back, and although she's not big, it's still a not inconsiderable extra amount of weight. The wind was pretty strong, and so the flag pole on the side with a couple of flags was bent over, so a lot of additional force. And so I think what happened is was riding along in a slight curve (roads around the center are curved), and I think the tires lost traction somewhat (the mud is very sticky and tends to build up in the treads and stops them up, turning them into more smoothish), slide sideways some to the left, and then stopped sliding at the bottom of a rut. Except the rest of the trike, box and partner and wind on the flag pole and all, kept wanting to go left. And so spokes just broke and/or the spoke nipples just pulled right out of the rim. I think some pulled out of the rim, and then others just broke at the hub as more force was put on them. And of course, no spare spokes anywhere, and none of the bike repair camps (reasonably) had a spoke cutter/threader.

So in short... if you're going to put any significant weight on this sort of conversion, consider a stronger rim (do they even make steel bicycle rims anymore?), thicker spokes (at least 13ga, 12 ga better) or figure out some way to do more motorcycle or 'flat' spoke sorta wheels. Or maybe something like this chain drive differential with a jack shaft to convert bicycle chain (e.g. pedals) to the correct chain type.

Advice: If you're using general purpose bicycle parts... before of overloading or very rough terrain or just not using parts really under the stresses they were designed for, but far higher stresses. You'll eventually find the weakest part. And then you'll find the next weakest part. Also, if you have something far out of the ordinary, maybe bring spares of things nobody else will (such as spokes).

I doubt I'll be going quite for this sort of lunacy again, at least not for quite some time. I say that now though...

 

[amberwolf]

Regarding rims and spokes...I use sapim 13-14g single-butted spokes on a simple doublewall aluminum rim for my heavy heavy cargo trike SB Cruiser (to carry hundreds of pounds of stuff or dog(s), etc), and don't have problems with those except the very few times I have had unavoidable interactions with sharp-edged potholes or large road debris falling off of vehicles, etc. Those tend to damage the rims, and once broke some spokes (but usualy the spokes remain intact even when the rim requires replacement).

They're 20" wheels, (probably heavy-duty BMX) 20"x40mm(?) rims with eyeletted nipple holes, moped tires (shinko sr714 16"x2.25"). Radially laced, sapim 13-14g single butted spokes from ebikes.ca laced up by me.


Most of the wheel problems I have ever had were caused by factory-built wheels, mostly those with hubmotors in them, but regular ones off random cheap bikes too. Usually from poorly-built wheels improperly tensioned, and from too-thick spokes that then damage the rim because of the too-high tension required for thicker spokes.


So you don't want thicker spokes, you want *thinner* spokes, so they properly tension and stay tensioned, with eyeletted doublewall aluminum rims.


If you want to use thick spokes, you'll need to upgrade to rims that are capable of handling the tension they'll require--probably moped or motorcycle rims...but there really isn't any need for that under most circumstances. Even pedicabs that carry a half ton or more of people, in addition to their own weight, usually still use regular bicycle rims and thin spokes appropriate for the rims.


Excessive sideloading causing rims to bend is not uncommon in accidents...but unless you expect that sort of thing to happen it's not something you have to overbuild a wheel to deal with. If you do expect it to happen, then you may have to overbuild tthem; this might require motorcycle rims and spokes (which may also require MC hubs, as the bicycle ones probably can't handle the tension required for MC spokes especialy after being drilled out to acommodate the larger size, but you can also custom-make hubs to do it).

 

[Drizzt321]

So...I think this went even beyond that. These were double walled aluminum, but just WAY too much weight and force on them. Literally pulled the spoke nipples out of the rim. Although to be fair, I haven't been checking on spoke tension the last few years, so if they had been properly checked and tensioned they might have survived fine.

I don't want to continue with 20" wheels out there, at least not unless they're 3.5-4" fat tires, at a minimum. But I'd rather 24-26". But that's very specific to that terrain.

After reading up a bit more, yeah, thicker spokes only would be good with much heavier duty rim & hub, so what I need is a stronger rim (if I can find a steel double wall rim in the size I want), and the 13/14 Sapim Strong and, especially, properly tensioned. Along with a full set of spares _just_ in case when I'm out in the middle of nowhere.

I will say that pedicabs generally aren't used on used on things other than moderately smooth surfaces. Sure might be some potholes or gravel, but here's a few pictures illustrating the wet muddy surface, and then when it drives (after it's been ripped up by bikes, pedestrians, and especially vehicles) it dries hard like concrete and becomes extremely bumpy.

A mud covered bicycle leans on a metal rail in a wet desert setting. A geometric wooden art installation and distant mountains are visible in the back Stock Photo - Alamy

Download this stock image: A mud covered bicycle leans on a metal rail in a wet desert setting. A geometric wooden art installation and distant mountains are visible in the back - 3CHJ9D4 from Alamy's library of millions of high resolution stock photos, illustrations and vectors.

www.alamy.com

Muddy Road with Art Installations at Burning Man Festival 2025 Stock Photo - Alamy

Download this stock image: Muddy Road with Art Installations at Burning Man Festival 2025 - 3CHJCDE from Alamy's library of millions of high resolution stock photos, illustrations and vectors.

www.alamy.com

I also think the problem was I slide sideways a bit, and then the rest of the weight effectively slammed into the wheel hub which pulled sideways, rather than the normal compression/pulling force that is exerted between the hub and rim through the spokes. If it hadn't been pushed sideways, I think it would have survived just fine, even with my spokes not fully properly tensioned up.

Or maybe, and this is crazy, but what about thin steel washers the spoke nipples fit into to help spread any major pull (e.g. being forced sideways to get pulled out) to spread the load further on a well made aluminum double wall rim?

The question is how to reinforce for a significant sudden sideways force with the wheel hub being pushed out away, almost perfectly perpendicular, to the rim and keep the spoke nipples from being pulled out or the butts at the hub from being snapped? 13/14ga can help with being stronger at the hub from lateral forces, but the other?

The other thing I saw actually, was someone in a tadpole recumbent with a small 1-wheel towbehind trailer. Maybe the Bob Ibex? Looked similar anyway, after doing a bit of searches. So maybe something like that, or a 2 wheel cart/trailer with a very good hitch/connector might be a lot easier and sufficient. And let's me use pretty much any style of recumbent, as long as I ensure a good strong hitch connection. But that's for planning at a different time.

 

[amberwolf]

If the rim is failing during the sideloading, then you'd need a stronger rim in the specifc ways that the one that failed isn't.

If it fails at the nipple holes, then perhaps belleville (?) washers (possibly inverted so they're not used as springs, just cups, but this is probably wrong), to help spread the load across more of the internal rim surface, and making sure you have eyelets on those holes to reinforce them. (you will need washers that do not themselves deform like you would with a spoke flange washer at the elbow, or it won't spread the load over the rim internals the way you want). The washers may have to be shaped to correctly apply their load to the curved rim surface, so more saddle-shaped at the rim surface side instead of flat--this will complicate the lacing and tensioning process.

If it fails at the spoke elbows, immediately during the sideloading, then the forces on the spokes are more than they can take and you'd need larger spokes (and hub and rim) to fix that.

If it fails at the rim structure itself, tacoing without ripping nipples thru or breaking spokes, then a (laterally) stronger rim would help with that.

Etc.


To fix/prevent any particular failure in anything, you have to see how the failure started, and progressed, and ended. This takes some imagination, some study of the actual parts involved, and some knowledge (or research) of how the parts interact and are supposed to function, so that you can see how they *didn't* function and then figure out how to fix that.

That's one process I'm reasonably good at.


The delta trike I ride works with the smaller wheels well for sideloading, but the ride is pretty crappy during the large proportion of nonsmooth roads around here. The one I'd like to build (thread around here somewhere) would use 29" wheels, but probably won't handle sideloading as well, because the larger diameter wheels experience stresses in taht way differently than smaller ones.

SBC, for instance, can be drifted around a corner if I do the braking and steering just right, but I might not be able to do that with such large diameter wheels as I want. I can live with that for the ride quality improvement.

 

[Drizzt321]

Yeah, I'm certain it was during significant sideloading. And pretty sure it _started_ with spoke nipples being pulled out (e.g. rim spoke holes). I'm pretty sure that the spokes broken at the elbow were secondary after some of them pulled out of the rim and thus imbalanced and actually flexed the spoke at the elbow as even more sudden lateral loading was put on as more of the weight and force got put on fewer spokes as the hub vs rim got further out of proper alignment.

In short, if I could fine some rim spoke eyelets that'd be nice, or those belleville washers you mention, that might be viable. Or something similar.

Should I go to do something vaguely similar, I'll be sure to make a new post. I do have some Atomic Zombie plans I bought a while back, perhaps I'll dust them off and make some tweaks. Maybe variant of the Loderunner with some shocks or Aurora, and perhaps using an IGH as a jack-shaft from a standard mid-motor/pedals to one of those AliExpress chain drive differentials.

EDIT: This thread seems to have some relevant information spoke nipple diameter

Oh look, and Sapim has some spoke nipple and elbow washers Washers | Sapim