My armchair engineering ebike

[TwisterGripper]

I am looking in the 1500 (cont/3000wpeak) power range to achieve around 60kph top speed, and would like to still have a 7 speed freewheel or ideally a 9 speed cassette on it.

That's a job for Leaf Motor 1500W. For future-proofness, get a freewheel model (which has a better axle and versatile freewheel interface. You can get good quality 8, 9, 10-speed freewheels from SunRace, though once you have >1kW on tap, having lots of gears isn't important at all.

Thanks for the tip - had no idea about the larger freewheels - i like to pedal still, and increase range.
Why the Leaf motor over other options? Does it offer the best value/performance/features mix compared to others? I just started looking at the 1500-2000w options and its very difficult to find/compare. Especially with all the aliexpress listings giving close to zero information on specifics.
I remember on Toms Hardware forums they would post a yearly "best buy" components list for building pc's - is there something like that on ES forums that you know of?

 

[Chalo]

Why the Leaf motor over other options? Does it offer the best value/performance/features mix compared to others?

Right now? The benefits of the Leaf 1500W are weight, excellent efficiency, decent build quality, and custom winding count (which is to say, custom RPM per volt) at no extra charge.

It's not as much of a bargain as it was a couple of years ago, but it's still price competitive.

To get a special winding, tell them in the order notes what wheel diameter and voltage you're using, and what top speed you'd like (though it must be a speed that 1500W will support).

 

[TwisterGripper]

....custom winding count (which is to say, custom RPM per volt) at no extra charge...tell them in the order notes what wheel diameter and voltage you're using, and what top speed you'd like (though it must be a speed that 1500W will support).

cool, I havent decided on 20"24"or26" wheel yet, likely to go with 48v or 52v battery pack (price, availability) - what would you recommend for a 60kph top speed?

 

[CONSIDERABLE SHOUTING]

cool, I havent decided on 20"24"or26" wheel yet, likely to go with 48v or 52v battery pack (price, availability) - what would you recommend for a 60kph top speed?

Not gonna lie to you bro- don't even try. 40MPH/60KpH is gonna require a battery that can pump serious amps, an expensive controller in the ASCI/APT range (they're also huge aluminum bricks too) and a fairing for wind. Check Dui's thread here on his Ninja 250 clone to get an idea of what it takes, I think his bike tops out at 100KpH or so. Peep the size of the controller.
Believe me; sometimes, 25MpH/40KpH is sometimes very fast on a bike :lol: and the energy needed to defeat wind resistance above 35MpH is actually somewhat considerable. Personally- I'd focus on turning what you've got into something with good parts and see what you get. You genuinely might have something that can do 30MpH, and never hit that speed again lol

 

[TwisterGripper]

cool, I havent decided on 20"24"or26" wheel yet, likely to go with 48v or 52v battery pack (price, availability) - what would you recommend for a 60kph top speed?

Not gonna lie to you bro- don't even try. 40MPH/60KpH is gonna require a battery that can pump serious amps, an expensive controller in the ASCI/APT range (they're also huge aluminum bricks too) and a fairing for wind. Check Dui's thread here on his Ninja 250 clone to get an idea of what it takes, I think his bike tops out at 100KpH or so. Peep the size of the controller.
Believe me; sometimes, 25MpH/40KpH is sometimes very fast on a bike :lol: and the energy needed to defeat wind resistance above 35MpH is actually somewhat considerable. Personally- I'd focus on turning what you've got into something with good parts and see what you get. You genuinely might have something that can do 30MpH, and never hit that speed again lol

Maybe your comment was meant for OP - sorry don't mean to be hijacking this thread. that ninja 250 is using a 3000w continuous (6000w peak) motor capable of 70kph+ - that is way more power than i want/need. 1500w/3000 peak is much more achievable on a low budget. Also, I'm no stranger to speed on 2 wheels, did some 600cc motorcycle road racing back in the day...

 

[The Madmadscientist]

Hello and thanks for answering my post.
Yes, the 'hide all the electronics' issue is real.
I've planned out two motorcycle hard case saddle bags which should mount to my rear rack.
I've included pictures of the cases, the rack and what this frame looks like when it's a bicycle except its not the exact frame.
One of the reasons that I am doing this is because I like how the frame looks and don't want it to be covered up.
I think I've answered all of your questions.

Okay, well... The saddlebags will totally work, and I would suggest keeping the luggage to a rear rack and using the bags for all batteries and electronics. Space will be a premium, and weight distribution might be an issue but frankly, I'm just parroting what I've heard from more experienced opinions I trust. Because of that space issue, you might have to stick to the 750w -> 1500x size for your motor since it's more likely you'll be able to fit that battery in them. I'm not sure what range and top speed you'd like- or even how you want to run the motor- but I imagine from looking at those, a 13s3p pack of 2170s should be easily doable but I imagine you'll be splitting the battery between the two packs (which isn't complicated, but might be a bit of a pain :wink: ).

Rear rack- to keep the aesthetic, I'd try to build one instead of buy one if you like that frame enough to stick with it. Probably have a bit of a duck tail? Not sure how i'd work it into the chopper look.

Hiding electronics- In my view, you'll want to run the wiring in a loom of some kind alongside the brake and shifter cables to keep the appearance instead of cutting into the frame and potentially lowering it's rigidity and safety. I'm not sure how you want to control the motor just yet, but if you want a super-clean look you could do a twist throttle with a voltage display on one side and a small percentage meter on the other- that could be only ~4-5 wires back to the controller so they'd be hard to spot, if you don't want something like PAS. All depends on what you'd like tho, I totally understand not wanting entire heads-up displays but I find ancillaries like lights really nice "Quality of life improvements" to have.

Hi,
I had to do some searching for saddle bags that were big enough to hold the proposed battery and controller and all other electronic gizmos. The bags in the picture would allow for a battery with a max size of 482mmL by 190mmW by 216mmH.
I've been talking with several battery manufactures about a custom size battery. My specs for the battery so far are pretty simple...I think a 72V 20Ah NMC 21700 with a 60A continous rating battery pack would be ideal. The quotes I'm getting back the battery will take a little less than half of the space. I've tried to go longer than high or wide. On the other side case will hold the controller, the step-down dc-dc converter for all the ancillaries meant to be used in cars/motorcycles. This will bring down the 72V to 14.5V. I will build a false floor to protect the electronics from the groceries. I've been toying with the idea to cut a hole in the bottom of the bag so I can mount the Sabvoton controller with its fins out to catch some cooling air.

I plan to really pump those pedals. I am not going to be one of those folks who never pedal their ebikes...so yea a PAS sensor would be great..I wish there was a way to use those aliexpress torque sensors...

Yes on hiding all the wires and bike cables in one black loom that runs from front to back. I'll need at least one relay to feed the lighting.

For the display, I'm happy with the UKC1 its not miniscule but I like my real-time data.

Rear rack is going to be almost completely covered by the 'chopper esque' hard cases so I am fine with the rack shown. It has a 110 pound rating.

Think that's everything...

 

[The Madmadscientist]

The horizontal dropouts and the lack of a derailleur mount means that the bike is meant to be a single gear or have an internal geared rear hub. Neither of which would be desirable on a commuter/cargo bike that you intend to install a hub motor on.

Thanks for catching the 'no derailer dropout thing'. I totally missed it.
I was sunk for an hour but did some googling and found that universal derailers exist that attach to the axle. Shimano makes a decent one apparently.

"Direct mount" derailleurs exist, but they're for through-axle frames. What you need is a separate hanger. They're are two basic kinds. The common one is for front opening dropouts:

Less common, but still easy to find, is a hanger for rear opening dropouts like those on track bikes and some cruisers:

Are you sure that the direct mount derailers are only for thru axles...I swear I saw a pic, which of course I can't find now, that showed it otherwise. Thanks for the pick of the horizontal adapter my rear dropouts are horizontal.

 

[amberwolf]

I plan to really pump those pedals. I am not going to be one of those folks who never pedal their ebikes...so yea a PAS sensor would be great..I wish there was a way to use those aliexpress torque sensors...

Unless there is something in your frame choice specifically preventing it, there's no reason you couldn't use a BB cartridge torque sensor. If it has an output compatible with the Cycle Analyst v3 from Grin Tech, you can use the CA to interpret the sensor and any other inputs you wish to use (throttle, etc), process them from whatever settings you choose in it, and generate a throttle signal compatible with any controller to drive the motor the way you want it to.

Even if you can't use a torque sensor, the CA can still easily be used with a pulse-type "cadence" PAS sensor to control the motor's speed or power by how fast you are pedalling. (most controllers that use this type of PAS sensor only detect that you *are* pedalling, and then supply full assist at whatever level was chosen on the controller display, etc; you can't control it finely like with a throttle or the true cadence-control method like the CA can generate).

 

[amberwolf]

Are you sure that the direct mount derailers are only for thru axles...I swear I saw a pic, which of course I can't find now, that showed it otherwise.

This might be helpful:
https://wheelsmfg.com/blog/standard-mount-vs-direct-mount-derailleur-hangers.html
if you haven't seen it already. I don't know which axle types they show, but at least one looks like a QR, rather than thru hole?

 

[The Madmadscientist]

I plan to really pump those pedals. I am not going to be one of those folks who never pedal their ebikes...so yea a PAS sensor would be great..I wish there was a way to use those aliexpress torque sensors...

Unless there is something in your frame choice specifically preventing it, there's no reason you couldn't use a BB cartridge torque sensor. If it has an output compatible with the Cycle Analyst v3 from Grin Tech, you can use the CA to interpret the sensor and any other inputs you wish to use (throttle, etc), process them from whatever settings you choose in it, and generate a throttle signal compatible with any controller to drive the motor the way you want it to.

Even if you can't use a torque sensor, the CA can still easily be used with a pulse-type "cadence" PAS sensor to control the motor's speed or power by how fast you are pedalling. (most controllers that use this type of PAS sensor only detect that you *are* pedalling, and then supply full assist at whatever level was chosen on the controller display, etc; you can't control it finely like with a throttle or the true cadence-control method like the CA can generate).

I don't know anything about the cycle analyst. Does it replace a standard display like the UKC1?
Time to get to learning....it's too hot here 100 in Berkeley and everyone is losing their minds...

 

[The Madmadscientist]

Bummer!
Just got an email from Schmulf....They don't have a solution that will work with me fat bike BB.
The dia of the BB is 40mm acording to Tracer....they said that they couldn't match it....
I've looked and can't find anything that will fit a 40mm wide BB?
They want a BSA BB of 34mm.
seems like there should be an adaptor.
I'm hoping the tracer guy got it wrong...I'm checking with them today.

 

[Chalo]

Schlumpf two speed BBs use conical interfaces on the BB shell to transmit reaction torque. If the conical surfaces bear on adapters, the adapters are likely to spin around.

Maybe you could have someone machine press fit adapters with conical edges, but bond them into the frame bores with epoxy or cylindrical fit Loctite.

 

[amberwolf]

I don't know anything about the cycle analyst. Does it replace a standard display like the UKC1?

It's not a display for a controller; it's a separate computer that just processes various sensor inputs thru settings you choose to create a throttle signal to drive a controller in a way the controller itself isn't capable of. (if a controller is capable of it, you wouldn't need to use the CA ). It doesn't communicate with your controller, etc. It doesn't have to be placed where you can see it to do it's job, but sometimes the info it can display is useful during initial setup / usage, and for troubleshooting a problem.

So any controller that uses a display to access it's own settings, etc., or display info from the controller, will still need that display.

https://ebikes.ca/product-info/grin-products/cycle-analyst-3.html

There is a bit of a learning curve in using it, as it can do quite a variety of things, and not all of them are needed by most people; deciding which ones you want to use, and setting it up to just use those things, the way you want them to work, takes some work. There's videos on that page if you prefer that sort of learning, or manuals attached to it, and this very long thread
https://endless-sphere.com/forums/viewtopic.php?f=4&t=37964&hilit=cycle+analyst
that discusses many ways to use it, and how features work (and how they have evolved over the years in different firmware versions). If you do use that thread, start with the first few pages to get the gist, then start looking back from the end to see more recent functionality.

Time to get to learning....it's too hot here 100 in Berkeley and everyone is losing their minds...

Only 100? That would be a nice cool change for me.

 

[E-HP]

Time to get to learning....it's too hot here 100 in Berkeley and everyone is losing their minds...

Only 100? That would be a nice cool change for me.

It's oddly hot. I'm used to a dry 110, but it feels hotter than that even though it only hit 99 today. Maybe more humidity, maybe the still air, but I went out for a ride, stayed mostly in the shade, but it was as hot in the shade as in the sun. I rode back home after 20 minutes. I felt like throttling all the way back, but it was cooler riding slow, since riding fast felt like a blast furnace with the hot air hitting you. Very strange weather.

 

[E-HP]

I don't trust those tires...

https://endless-sphere.com/forums/viewtopic.php?f=3&t=114679&p=1695762p1695762#p1696075

 

[The Madmadscientist]

I don't trust those tires...

https://endless-sphere.com/forums/viewtopic.php?f=3&t=114679&p=1695762p1695762#p1696075

I'm planning on using 26by4 wide white wall tires with street tread. Not a lot to choose from unfortunately. They are surprisingly expensive...

Your blowout reminded me of when a friend and I filled up the tires on our Schwin scramblers until they were as hard as a rock. We liked how easily they rolled. Got about 2 blocks we stopped at a pet store to look at the fish and BOOM!!! My tire blew. It was so loud that everyone rushed outside.
There was just our two bikes and no evidence...hated having to walk my bike home...

 

[e-beach]

........hated having to walk my bike home...

Yep ,informally known around here as "The walk of shame." Just another reason why keeping an extra tire on the shelf is a prudent idea. People around here try all kinds of things to make their tires puncture proof, but just wait until you get a drywall screw plunged through your sidewall where there is little puncture protection. Ask me how I know. And yes, I did a three mile walk of shame with that one.

As for tires, you might consider scooter or motorcycle tires.

https://endless-sphere.com/forums/viewtopic.php?t=55458

 

[The Madmadscientist]

Well, hot damn,

Was contemplating my 'no rear derailer dropout' issue yet again.
I went to look back at the other pictures of the proposed frame and realized this.....that the frame shot I shared is the exact wrong one.

Another shot clearly shows the dropout.
Yay!!! A break! Check out the puc below.

A note for those of you who shake your head and say, 'he thinks he's going to do this on a budget' I can hear the smirking you know.

When I say budget I don't mean cheap.
I mean that I will research the hell out of every last widget I need. Then I make a decision about which parts to buy.
If I can't afford to buy the correct part at once then I'll have to wait till I can. I don't cheap out.
Remember when I said that building this bike up was going to be a long term process?
I mean jeez guys, do you have to be so ruff on the new guy?

 

[e-beach]

.....I mean jeez guys, do you have to be so ruff on the new guy?

Well, because ES is actually a frat-house full of many mad-scientists. :wink:

 

[Chalo]

I went to look back at the other pictures of the proposed frame and realized this.....that the frame shot I shared is the exact wrong one.

Another shot clearly shows the dropout.

It also shows the BB shell, which looks like a regular threaded one (though unusually wide). I think the person who told you 40mm was talking about the outside diameter and not the bore diameter.

 

[The Madmadscientist]

I went to look back at the other pictures of the proposed frame and realized this.....that the frame shot I shared is the exact wrong one.

Another shot clearly shows the dropout.

It also shows the BB shell, which looks like a regular threaded one (though unusually wide). I think the person who told you 40mm was talking about the outside diameter and not the bore diameter.

That is exactly what I am hoping. I sent Tracer an email about it but have not heard back from them.
I've found bearings for a 41mm BB but not a 40mm.

 

[amberwolf]

That is exactly what I am hoping. I sent Tracer an email about it but have not heard back from them.
I've found bearings for a 41mm BB but not a 40mm.

Sounds like time for a direct measurement. Even a cheap digital caliper (random google link:
https://www.amazon.com/Digital-Caliper-Adoric-Calipers-Measuring/dp/B07DFFYCXS ) would let you do a good enough ID measurement to be pretty sure of which kind of BB shell it is.

This page lists a lot (all?) of the standards used (at least, almost certainly any yours might be):
https://wheelsmfg.com/bb-standards

 

[The Madmadscientist]

That is exactly what I am hoping. I sent Tracer an email about it but have not heard back from them.
I've found bearings for a 41mm BB but not a 40mm.

Sounds like time for a direct measurement. Even a cheap digital caliper (random google link:
https://www.amazon.com/Digital-Caliper-Adoric-Calipers-Measuring/dp/B07DFFYCXS ) would let you do a good enough ID measurement to be pretty sure of which kind of BB shell it is.

This page lists a lot (all?) of the standards used (at least, almost certainly any yours might be):
https://wheelsmfg.com/bb-standards

Hi and thanks for that link.
I've been feeling overwhelmed with trying to spec the correct complete crankset.
Yes, definitely, I will measure the BB just as soon as I have that silly frame in my grubby hands.

 

[LewTwo]

The problem being that much like FreeWheel threading, it may not translate to Chinglish.

FYI:
A standard "ISO 1.375 x 24 TPI" (34.92 x 1.058 mm) FreeWheel thread in Chinglish is translated to "34 mm inner diameter" and frequently labeled simply "34 mm".

 

[LewTwo]

My plan is to build up an ebike that is personalized to my tastes ...

Yo, Daniel .... have you seen this? Looks a bit like they had you in mind.
https://www.amazon.com/dp/B08Y1VVW7Z