Planning ultralight, stealthy, silent build, questions..

E-HP

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When i first came on this forum, i tried to build the same kind of bike you're talking about.. of course my preferences changed over time.. this may happen to you too!
The lightest/stealthiest option I've seen on ES is Kepler's friction drive, which is much lighter than a hub, inconspicuous, and provides the low level of assistance, appearing to match the OP's criteria.
20200809_143435-jpg.277930
 

croowley

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Kinda sad to see this getting snarky.

croowley, is this your first bike build?

If so, please don't shoot for perfection up front.. you don't know what you don't know, you also find out what you really want after a first build. Don't let your first big problem be axle fitment though, i suggest keeping that part simple and straightforward.

When i first came on this forum, i tried to build the same kind of bike you're talking about.. of course my preferences changed over time.. this may happen to you too!

So tell me the issues instead of calling me out like this. I´m here to get help I don't know why you guys have this kinda attitude?
What´s the issue exactly? What is snarky, foolish, arbitrary and fad chasing?
Should I change forum?

Simple and straightforward as in easily manufacturing a custom part?

I know my preferences and I´m here to build a bike.
 

neptronix

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So tell me the issues instead of calling me out like this. I´m here to get help I don't know why you guys have this kinda attitude?
What´s the issue exactly? What is snarky, foolish, arbitrary and fad chasing?
Should I change forum?

Simple and straightforward as in easily manufacturing a custom part?

I know my preferences and I´m here to build a bike.

I'm saying the thread overall got snarky, not pointing all the fingers at you.

No need to change forum. I hope you get the help you need.

Just suggest you keep things simple and flexible if this is your first build. Nobody's first ebike conversion is their last.. :)
 

croowley

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The lightest/stealthiest option I've seen on ES is Kepler's friction drive, which is much lighter than a hub, inconspicuous, and provides the low level of assistance, appearing to match the OP's criteria.
20200809_143435-jpg.277930
Surely we can beat that. I like it, any link?

I'm saying the thread overall got snarky, not pointing all the fingers at you.

No need to change forum. I hope you get the help you need.

Just suggest you keep things simple and flexible if this is your first build. Nobody's first ebike conversion is their last.. :)
This will be my third, some things are completely new since I've had completely different bikes and I do appreciate the input I get but some seems a bit snarky ;)
 

E-HP

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So tell me the issues instead of calling me out like this. I´m here to get help I don't know why you guys have this kinda attitude?
What´s the issue exactly? What is snarky, foolish, arbitrary and fad chasing?
Should I change forum?

Simple and straightforward as in easily manufacturing a custom part?

I know my preferences and I´m here to build a bike.
I've been involved with, and led, a few projects that I felt had little chance of coming to fruition, but they did. The key was to invest time in a well thought out, well defined, and comprehensive goal, and ensuring any actions directly support the goal. That means if you have a solution to an issue that adds weight, no matter how little, it's not a complete solution unless you have something to offset that increase, and hopefully reduce the overall weight. You'll get help if you are serious and treat it that way. Things like aesthetics are squishy and undefined, so you'll need to address those yourself.
 

E-HP

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Surely we can beat that. I like it, any link?
It wasn't a one and done solution, so interesting to see the R&D evolve.
 

Chalo

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The lightest/stealthiest option I've seen on ES is Kepler's friction drive, which is much lighter than a hub, inconspicuous, and provides the low level of assistance, appearing to match the OP's criteria.
20200809_143435-jpg.277930
My limited observation of bikes that use toy airplane motors is that they make a conspicuous robotic noise. Probably a sine or FOC controller would reduce this.
 

E-HP

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My limited observation of bikes that use toy airplane motors is that they make a conspicuous robotic noise. Probably a sine or FOC controller would reduce this.
Problem identified; possible offsetting solutions provided, remaining consistent with the goal (y)

I haven't heard the Kepler version, but the commercial versions definitely not silent, and I think having knobby tires contributes to more noise as well.
 

neptronix

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RC motors are the furthest thing from silent as they often have open cases and high RPM... start with a huge disadvantage there vs hub motors which spin much slower.
 

99t4

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Motors 36 spokes, all rims I find within budget are 28 or 32 spokes what´s up with that?

What is your budget?

You will all laugh and I don´t need doubt and impossibilities. Let´s see where it lands ;)

Hey I was asking not to shame you or make fun of you but in hopes for someone to share a decent rim they know of that falls within your budget. Good luck finding a solution.(y)
 

Chalo

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croowley

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I've been involved with, and led, a few projects that I felt had little chance of coming to fruition, but they did. The key was to invest time in a well thought out, well defined, and comprehensive goal, and ensuring any actions directly support the goal. That means if you have a solution to an issue that adds weight, no matter how little, it's not a complete solution unless you have something to offset that increase, and hopefully reduce the overall weight. You'll get help if you are serious and treat it that way. Things like aesthetics are squishy and undefined, so you'll need to address those yourself.

Thank you.

Hey I was asking not to shame you or make fun of you but in hopes for someone to share a decent rim they know of that falls within your budget. Good luck finding a solution.(y)
All good man but I know some will you know (y)

Wow those are light! Nice!
 
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nicobie

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If you fabricate out of steel you don't need to add torque arms.
As the steel on these motor's axles are crap I think torque arms are a necessity especially if you want regen. Every right thinking person should want regen. Saves on brakes, saves on battery. To be honest I can't think of a reason to not want regen other than your bike can't take it without breaking. If so, time for a different bike. :mrgreen:
 

nicobie

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Note for your planning purposes that if "28H" means 28 holes/spokes, you may not be able to lace one with a hub motor, but they'll work for the mid drive, friction drive or other non-hub options.
Looks like you can get one in 32 and 36. however one will set you back ~$300
 

E-HP

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As the steel on these motor's axles are crap I think torque arms are a necessity especially if you want regen. Every right thinking person should want regen. Saves on brakes, saves on battery. To be honest I can't think of a reason to not want regen other than your bike can't take it without breaking. If so, time for a different bike. :mrgreen:
I'd agree normally, but due to the weight restriction, seems like a direct drive motor is out of the running, and my assumption is the motor will be a pretty small geared hub, so steel dropouts would suffice. He could weld the clutch to get regen, but then coasting is affected.

I miss regen <sigh>. The impact of not having it is twofold; a noticeable reduction in range and an increase in charging time, the second being worse.
 

Chalo

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Note for your planning purposes that if "28H" means 28 holes/spokes, you may not be able to lace one with a hub motor, but they'll work for the mid drive, friction drive or other non-hub options.
That outfit will customize rims, and drillings are just about the easiest thing to customize.
 

99t4

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I miss regen <sigh>. The impact of not having it is twofold; a noticeable reduction in range and an increase in charging time, the second being worse.
Threefold for me: (third) increased brake pad wear.
 

croowley

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Alright people.. How´s your evenings?

List is coming together somewhat..

According to my semi-accurate estimations we are well below 10kg with the g310 and rigid fork which was my plan from the beginning but I had a very good deal on a SID XX so with another kg to add I'm now speculating how to remove some weight elsewhere.

Read some blog that I cannot find again about reducing weight in the motor by changing parts to alu..
Question is, what parts can be exchanged for different materials except the most obvious ones..?
Can I for example replace heavy disk/plate holding gears for alu or even carbon without compromising performance?
According to the blog, up to 500g could be saved on a larger slightly larger hub motor..

Don't really care if u think it´s worth it or not , just wanna know what´s possible alright :)
 

glennb

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I don’t know how feasible any of that is.

It requires a degree of mental exercise that only a person interested in implementing the idea for themselves would consider undertaking.

But if you can dig up and post a link to the blog, that would alleviate some of the brain strain and could lead to constructive comments.
 

motomech

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I started out trying to build super stealthy bikes until I realized nobody cares.
If I was going to try to do it again I'd follow these tenets.
The bike doesn't have to be super lite or invisible, it just has to be something that when people look at it, they don't SEE it.
1) Start w/ a blk. or very dark bike and use Blk. wires exclusively.
2) The motor only needs to be slightly smaller than the brk. rotor/big chain ring to be hidden, so the Q100 is small enough. There most likely are better (Stronger, quieter, smoother) mini geared motors, but the Cute works ok and saves money to put into the battery.
3) No controller lights on the h.bars.
4) To hide the batt., it has to fit into a water-bottle shaped container that's not too big. The only way I could do that is to use Lithum Polymer custom fitted inside a spun alum Stanley single wall thermos. I could get 5 Ah.s. of 12S (44 V) inside for around 7-8 miles. But it was easy to carry another and swap them out for the trip home.
The vast majority of folks didn't realize it was an Ebike.
 
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croowley

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I don’t know how feasible any of that is.

It requires a degree of mental exercise that only a person interested in implementing the idea for themselves would consider undertaking.

But if you can dig up and post a link to the blog, that would alleviate some of the brain strain and could lead to constructive comments.
It took some heavy history digging but here it is
85f1263532e417c674374af8b5f4ea13.png
 

glennb

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Thanks for that.

He posts here, you could PM him.

The thing is, it’s hard to imagine who’d put the effort in.

Those most keen to minimise weight will already be using RC motors.

The small group of people using hubs as mid-drives (to achieve large gear reductions more easily than is possible for RC motors), use mini motors, which don’t have much fat on them.

A 3.5kg motor like the XiongDa, sure, but weight weenies won’t touch this motor weight class even if they could shed half a kilo from them.

You were interested in a 2.5kg Bafang, which is sort of a large mini motor. Knocking half a kilo off that might start to interest people, but not enough for them to be bothered when they can buy a 2.1kg AKM-100H instead.

The candidate motor would need to have some hugely redeeming qualities to make it worthwhile. If you can find such a motor, you’ll get help with it.
 
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