My armchair engineering ebike

The Madmadscientist · Jul 25, 2022

Hello All,
This is only my second post here but I think I got the correct sub-forum

My plan is to build up an ebike that is personalized to my tastes (goofy).
This will be a do everything bike as I don't own a car or motorcycle currently and don't care too. Im on the old side, 53, and find that I now need help doing what I could easily do in my 30's.

My admittedly vague plan so far.

I want to do an actually rideable fat tire semi-chopper ebike. My plan is to buy parts slowly as funds become available but guess it would take ~6-9 months for completion. Yes I plan on using the cheap Chinese product sites as much as reasonably possible.

My goal is to hide the fact that the bike is an ebike as much as reasonably possible.

I like the tracer sienna frame. I'm hoping I can add a rack and fenders.
I like the black/chrome springer fork.
I'm planning on some kind of fat bike rims, preferably red with 4" white wall tires.
I'm thinking of using hard case motorcycle panniers to hide the electronics and battery.
I would use 4-pot disk brakes with 203mm floating disks.

Because of cost and esthetics I think I'm going to be forced to use a rear hub motor. The panniers should almost completely hide it.
I do personally think that mid-mount motors are better but how would you hide it? I really like the CYC stealth model.

Is it nuts to want to run all the cables inside the frame?

I'm a physicist/fire artist/freelance imagineer so I should have the skills required...famous last words I know.

I would appreciate any thoughts on this admittedly early stage plan/idea.

Thanks,
Daniel

spinningmagnets · Jul 26, 2022

welcome! Looks like a fun project...

Chalo · Jul 26, 2022

The Madmadscientist said:
I do personally think that mid-mount motors are better but how would you hide it?

You wouldn't. It's on display by default. You could fit one into that weird frame, up inside the "triangle", but you'd have to lose the chainguard.

Is it nuts to want to run all the cables inside the frame?

Yes. The wires are easily damaged at the entry and exit points, it's extremely time-consuming to install, tedious to troubleshoot or replace anything, and the only benefit is to appease an infantile need to not see necessary components of your bike. Expensive road bike makers are hiding all their cables and hoses lately, and it's madness. Simple and cheap maintenance tasks turn into expensive, lengthy ordeals. Don't even get me started on Van Moof fashion victim e-bikes. I won't work on them anymore.

But if that's what cranks your knobs, well, you do you.

99t4 · Jul 26, 2022

The Madmadscientist said:
This will be a do everything bike as I don't own a car or motorcycle currently and don't care too.

To me, a "do everything bike" means some large proportion of it needs to be practical, as in able to carry groceries/liquids, comfortable over rough pavement, work well in all weather, able to lock up for short periods of time without worrying, easily repairable, parts availability, etc.

What are your other requirements outside of style?

In the late '70s I rode a Honda 750-4 chopper as my "do everything bike" but it wasn't well-suited to "do everything." More like 10% of everything :lol: . Everything else was a hassle.

amberwolf · Jul 26, 2022

Chalo said:
Is it nuts to want to run all the cables inside the frame?

Click to expand...

Yes. The wires are easily damaged at the entry and exit points,

Additionally, if hte holes for these are in the wrong places, the frame is compromised and can fracture and break there, potentially causing a serious crash.

(I ran wires thru my tiller on SB Cruiser, and that eventually broke off, essentially leaving me with the handlebars and half the tiller in my hands. Thankfully I was just pushing the trike into the yard after coming home, rather than riding on the road in traffic....).

amberwolf · Jul 26, 2022

The Madmadscientist said:
This will be a do everything bike as I don't own a car or motorcycle currently and don't care too.
<snip>
I want to do an actually rideable fat tire semi-chopper ebike.
<snip>

I like the tracer sienna frame. I'm hoping I can add a rack and fenders.
I like the black/chrome springer fork.
I'm planning on some kind of fat bike rims, preferably red with 4" white wall tires.
I'm thinking of using hard case motorcycle panniers to hide the electronics and battery.
I would use 4-pot disk brakes with 203mm floating disks.

What is the order of your requirements? Do you need it to be looks-first, functionality second, or vice-versa?

What specifically does "do-everything" mean, and under what specific conditions? (terrain/hills, winds, road conditions, riding style, traffic, speed, weather, etc).

What is your specific definition of "actually rideable"?

For my own definitions of "actually rideable" and "do-everything", there are significant conflicts between some of your listed stuff, but they may not be so for your own. See my SB Cruiser trike thread, etc., for what works as my "do-everything". I suspect my requirements are more stringent and needs more expansive than yours

So we need to know what *you* need to do with it to help you find the best match of solutions.

The Madmadscientist · Jul 26, 2022

Chalo said:
The Madmadscientist said:

I do personally think that mid-mount motors are better but how would you hide it?

Click to expand...

You wouldn't. It's on display by default. You could fit one into that weird frame, up inside the "triangle", but you'd have to lose the chainguard.

Is it nuts to want to run all the cables inside the frame?

Click to expand...

Yes. The wires are easily damaged at the entry and exit points, it's extremely time-consuming to install, tedious to troubleshoot or replace anything, and the only benefit is to appease an infantile need to not see necessary components of your bike.

But if that's what cranks your knobs, well, you do you.

Hello and thanks for your candor it is much appreciated. Your 'weird frame' comment is fun.

The mid v hub thing is such a fine kettle of fish.
At this stage I haven't made a hard decision yet.
I admit that being an artist looks are important but I will always pick function over form.

Thankyou for your comments re hidden cables. It does seem to be a fashion item for fancy road bikes. Hidden cables is just one idea I'm noodling around in my rock box (head).

Daniel
Someday I'll have a cool signature here...

The Madmadscientist · Jul 26, 2022

Hello,

99t4 said:
The Madmadscientist said:

This will be a do everything bike as I don't own a car or motorcycle currently and don't care too.

Click to expand...

To me, a "do everything bike" means some large proportion of it needs to be practical, as in able to carry groceries/liquids, comfortable over rough pavement, work well in all weather, able to lock up for short periods of time without worrying, easily repairable, parts availability, etc.

What are your other requirements outside of style?

In the late '70s I rode a Honda 750-4 chopper as my "do everything bike" but it wasn't well-suited to "do everything." More like 10% of everything :lol: . Everything else was a hassle.

Well, my requirements are slightly vague at this stage but I want a bike that I can ride longish distances on. I live in CA on the Oakland-Berkeley border so I can access 6 cities before I have to hit a serious hill. So no offroading or inter-state travel.

It needs to be waterproof.
I need to find a large size rack so I can fit large size panniers. If I can fit a grocery bags worth of food in each plus one on my back that would be more than enough.

I get what you're saying bout a chopper. The folks at Tracer have been good about answering my questions. The distances between seat, pedals and handlebars seems reasonable.
I haven't done a mock-up yet but will before any dough is spent.

Daniel
Oakland Ca

99t4 · Jul 27, 2022

The Madmadscientist said:
It needs to be waterproof.

You mean water-resistant? :wink:

The Madmadscientist · Jul 27, 2022

99t4 said:
The Madmadscientist said:

It needs to be waterproof.

Click to expand...

You mean water-resistant? :wink:

Wellllll, as waterproof as reasonably possible....
There are a lot of waterproof electrical connectors.
I used to have this awesome heat shrink tubing where the inside was coated with a substance that would melt and make the connection waterproof.

Daniel

RunForTheHills · Jul 27, 2022

I don't think you need to hide the fact that it is an ebike. I see more ebikes than non-ebikes these days and they are legal to ride in California. If you are on a tight budget, don't have a car or motorcycle, and want this to be your primary transportation, I would consider picking up a used hardtail mountain bike at first. They are very easy to find in your area on Craigslist. Although I imagine there are lot of stolen bikes being sold in Oakland, so you need to be careful. You can always move the motor kit (and other components) to your dream frame at a later time. The advantage of buying a used bike is that it comes with all the components you need and building a bike from a bare frame is always a lot more expensive.

That said, I don't think the frame you showed would make a very good commuter bicycle. There is no clear way to install a rack on it and the unusual downtube and double top tubes will make it difficult to mount a battery. 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.

amberwolf · Jul 27, 2022

The Madmadscientist said:
I used to have this awesome heat shrink tubing where the inside was coated with a substance that would melt and make the connection waterproof.

Marine Heatshrink (adhesive lined):
https://www.google.com/search?q=Marine+Heatshrink&tbm=isch

99t4 · Jul 28, 2022

The Madmadscientist said:
I used to have this awesome heat shrink tubing where the inside was coated with a substance that would melt and make the connection waterproof.

Yeah that part is easy. Much harder to waterproof the controller, motor, throttle, etc. Surprisingly, full fenders help quite a bit.

The Madmadscientist · Sep 3, 2022

Well,
Most of my armchair enginering is done. I think I've figured out all the widgets I need and where to buy them.
Eventough I'm making strong use of alliexpress the parts total surprised me.
If I did it right it's going to cost ~$2400....
It's a little bit more than I was expecting but doable. It just means that it will take me longer than I had originally expected to gather all the bits.
I am slighty bummed...stupid reality...always ruining my 'great' ideas...I never noticed that my dream frame doesnt have derailer mounts...dang it.

Was doing a google image search for chopper style ebicycles and I hit on a commercial product that freaking WallMart was apparently selling in 2018. I feel kinda dirty with me and WallMart having similar ideas...

TwisterGripper · Sep 3, 2022

The Madmadscientist said:
Well,
Most of my armchair enginering is done. I think I've figured out all the widgets I need and where to buy them.
Eventough I'm making strong use of alliexpress the parts total surprised me.
If I did it right it's going to cost ~$2400....
It's a little bit more than I was expecting but doable. It just means that it will take me longer than I had originally expected to gather all the bits.
I am slighty bummed...stupid reality...always ruining my 'great' ideas...I never noticed that my dream frame doesnt have derailer mounts...dang it.

Was doing a google image search for chopper style ebicycles and I hit on a commercial product that freaking WallMart was apparently selling in 2018. I feel kinda dirty with me and WallMart having similar ideas...

Hi Daniel, I was searching this forum for completed cruiser builds (still am actually) and came across your post. I'm looking to do something similar. - I want a cruiser style, because its really comfortable.

Right now, i have an Electra Lux fat bike XL (ebike converted) that a customer traded in - its too big for me, so i'll either sell it or strip it for the parts and sell the frame. How tall are you? if 6' or taller it might be a good fit for you if ur interested... it has a bafang 500w motor in the rear hub from Grin.ca, a kt 22 amp controller (new), KT lcd3 display (new) and a 36v, 21ah battery (couple years old but tests very very well) - it cruises around 40kph top speed and has decent pull (800watts while accelerating) thanks to the upgraded kt controller. I also have a cycle analyst I could part with if you are interested in using that as your display.

Riding the Electra Lux conversion bike is so damn comfortable and laid back - it has inspired me to build a cruiser for my daily driver road bike.

thoughts:
mid vs rear hub; I struggled with this. i was really leaning towards the BBSHD. But...after looking at some comparisons, decided rear hub (likely direct drive) is better for how i plan to use it. I plan to do a 1500-2000w rated build (3000-4000w peak).
I like that i won't have to constantly be shifting to be in the right torque zone as I would on a mid drive.
The motors cost less (some anyways). They are less hard on your drivetrain components. The power is all in the "fun zone" once you get rolling its all smiles and no hassle.
If i had steep hills or planned on off roading at all, i would go mid drive. Thanfully I have a mid drive mountain bike for that already. As for the "tire changes are a bi#@h" objection - I wont be putting enough mileage on this for that to be a concern.

The frame you posted - love the look, but every tube is curved, which will limit your battery mounting options. The Lux came to me with a battery bag that was hanging from the top tube. It was fugly, and the loops were tearing. I re-mounted battery to the seat tube (yes it was long enough!) and it looks sooo much cleaner - the seat tube was the only straight tube in the front triangle.
Other options would be buy a rack style battery for your rear rack, which you would be mounting saddlebags to...so another big component hidden, problem solved. Also that "stretched" frame design might force you to reach forward much more than an ergonomic design like the Electra Townie or Lux series...something to think about, especially if you plan to do longer rides (more than an hour for example) i think the position might become tiring.

as for hiding wires....i'd love to do this for the clean look too but i agree with the other posters that this just makes life harder, and could compromise the frame.

You didnt mention what kind of power and speed you are looking for. Would 500-800 watts adn 40kph be enough for you or are you looking for more like me?

If its not too much trouble, could you post the links or at least the brand/model/price info of the components on your list?
might help me with my search for parts. I haven't settled on which motor/controller/display to get yet.

LewTwo · Sep 4, 2022

Madmadscientist

If you have not seen the thread for OldskoolGrimace's "Stretch Cruiser" then you might want to take a look at it.
https://endless-sphere.com/forums/viewtopic.php?f=6&t=115376

CONSIDERABLE SHOUTING · Sep 4, 2022

Welcome!

I love the chopper look, but frankly I'm not sure how you'll keep the aesthetic with things like racks or saddlebags for groceries and the like. Maybe look to Harley's for inspiration on that front.

This is all the opinion of a newbie who only owns a half-broken Sondors so take this with a SERIOUS grain of salt (more like, horse salt lick) but... Don't hide it's eBike nature. For the sake of argument, we'll say you've settled on that frame- where would the battery go that isn't obvious? My only thought would either be at level with the chainguard leaving the top open, or under/inside the rear saddlebags next to the motor. One physically may not fit, the other is very exposed, both could be too small for what you wanna do unless you're comfortable with pouch cells.

Now this is a dumb idea but... how artistic are you? Because eBikers in the past have "dressed" up their battery packs to look like engine cylinders before, typically having the cells in 3D printed enclosures. I know of one, that used headway cells bunched together in a hexagon of 7 cells, then connected the two in series with "Spark plug wires" to even complete the effect! Not efficient at all and only good for 24v, but it's got style.
Here's some other ideas.

IF you want fat tires, you've gonna need motor power to overcome the grip. For the look, I can't see you going anything other than a hub motor to be frank; It'll look more akin to an old drum brake an integrated spline gear, instead of the more moped style of having an engine hanging off the front of the downtube.

e-beach · Sep 4, 2022

Trust the guys who say water resistant. You could use adhesive lined heat shrink tubing on your connectors, but just wait until your cheap Chinese part fails and you have no way to easily disconnect it and replace it. Throttles ware out, controllers burn out. Motor Hall sensors burn out. That kind of stuff happens all the time. So water-proofing is really a bad idea unless you have a way to access all your connectors and wiring when your part goes bad.

And, in fact a prudent thing to do is to keep spare parts on the shelf. At least one spare throttle, a set of brake levers, a spare controller, two inner tubs and one replacement tire. Not to mention connectors and appropriate wire types.

When your bike has a problem you will be more able to get up and going again without delay.

The Madmadscientist · Sep 4, 2022

RunForTheHills said:
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.

The Madmadscientist · Sep 4, 2022

TwisterGripper said:
thoughts:

The frame you posted - love the look, but every tube is curved, which will limit your battery mounting options. The Lux came to me with a battery bag that was hanging from the top tube. It was fugly, and the loops were tearing. I re-mounted battery to the seat tube (yes it was long enough!) and it looks sooo much cleaner - the seat tube was the only straight tube in the front triangle.
Other options would be buy a rack style battery for your rear rack, which you would be mounting saddlebags to...so another big component hidden, problem solved. Also that "stretched" frame design might force you to reach forward much more than an ergonomic design like the Electra Townie or Lux series...something to think about, especially if you plan to do longer rides (more than an hour for example) i think the position might become tiring.

You didnt mention what kind of power and speed you are looking for. Would 500-800 watts adn 40kph be enough for you or are you looking for more like me?

If its not too much trouble, could you post the links or at least the brand/model/price info of the components on your list?
might help me with my search for parts. I haven't settled on which motor/controller/display to get yet.

Hello and I appreciate the time it must of taken to write your reply.
Okay so, my 'list' is a saved shopping cart on Aliexpress and Amazon I'll see about getting you the links.
I'm planning on a 3000W high speed hub motor but thanks for the bike offer anyways.
To combat the stretch frame issue I've got an adjustable, long handle bar stem that I am planning on using backwards so I should be in a comfortable upright position.
I've also spec'd a longer seatpost to increase my butt to pedal distance if needed.
I taped out the frame on the floor and I think this setup should be comfy....
If I had all the money in the world I'd probably buy that new uber expensive IGH that can actually handle BBSHD torque and go for a mid drive eventhough all that exposed bits bugs my sense of style...

TwisterGripper · Sep 4, 2022

The Madmadscientist said:
Hello and I appreciate the time it must of taken to write your reply.
Okay so, my 'list' is a saved shopping cart on Aliexpress and Amazon I'll see about getting you the links.
I'm planning on a 3000W high speed hub motor but thanks for the bike offer anyways.
To combat the stretch frame issue I've got an adjustable, long handle bar stem that I am planning on using backwards so I should be in a comfortable upright position.
I've also spec'd a longer seatpost to increase my butt to pedal distance if needed.
I taped out the frame on the floor and I think this setup should be comfy....
If I had all the money in the world I'd probably buy that new uber expensive IGH that can actually handle BBSHD torque and go for a mid drive eventhough all that exposed bits bugs my sense of style...

Main thing im interested in is the motor choice. 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. Fat rear tire, big skinny front for that "chopper" look lol. The QS205 is more power than I need but seems popular....what are you considering?

The Madmadscientist · Sep 4, 2022

CONSIDERABLE SHOUTING said:
Welcome!

I love the chopper look, but frankly I'm not sure how you'll keep the aesthetic with things like racks or saddlebags for groceries and the like. Maybe look to Harley's for inspiration on that front.

This is all the opinion of a newbie who only owns a half-broken Sondors so take this with a SERIOUS grain of salt (more like, horse salt lick) but... Don't hide it's eBike nature. For the sake of argument, we'll say you've settled on that frame- where would the battery go that isn't obvious? My only thought would either be at level with the chainguard leaving the top open, or under/inside the rear saddlebags next to the motor. One physically may not fit, the other is very exposed, both could be too small for what you wanna do unless you're comfortable with pouch cells.

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.

CONSIDERABLE SHOUTING · Sep 5, 2022

The Madmadscientist said:
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.

Chalo · Sep 5, 2022

The Madmadscientist said:
RunForTheHills said:

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.

Click to expand...

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:

Chalo · Sep 5, 2022

TwisterGripper said:
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.

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