No cogging or with cogging, hmm

FurryOnTheInside

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#1
I'm being indecisive due to lack of experience. I thought I'd see what others have to say from their experiences. Particularly the cogging of non geared hub motors and the different battery types.

I'm trying to decide on an electric front wheel kit to be able to have a stealth mode for my "Night Fur(r)y" touring m'bike.
View media item 61364
I can have 36v and limited to 250w/ 15.5mph but "geared" for no drag when switched off..
Or I can have 48v 1000w /31mph but it will drag when switched off (and my 2T chain drive already drags enough).

I can't find any geared 48v front wheels or hubs, or even any geared 360W 36v/ faster than 15.5mph front wheels or hubs in the UK and Europe websites/ marketplaces. So it's just a choice between those two already mentioned.

If it get a 1000W 31mph top speed then its possible to use as an AWD dual power bike, and in stealth (E only) mode I could get well ahead of the cyclists I'm passing before restarting the 2T :cool:
but with the 250w, and the 15.5mph restriction, the 2T engine only makes real power and torque after the front hub exceeds its speed limit and cuts out, so no AWD :cry:
and with a weak and slow stealth mode I have to start the 2T right in the roadie cyclists' faces because I can't pull ahead. :oops:

So how annoying is "cogging" drag from a direct drive motor (in addition to the 2T chain/clutch drag)?
Do you have an experience with the two motor types to compare them?
 
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FurryOnTheInside

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#2
Anyway I think I'll get the cheaper low power low speed motor-front-wheel, because it has no mechanical resistance to rolling when the motor is switched off. So I can pedal some of the time, roll down hills etc, with only the resistance of the rear engine chain and clutch parts.

I really don't think I can add the extra mechanical resistance of the non geared 1000W or I'll never pedal the bike unaided (with momentum or gravity counts as unaided lol). I'll nearly always be using one motor or the other or both while optionally pedalling seldom unaided because the bike will roll even less well than it does already with the 2T on there.
Electric + Petrol AWD
Electric + Petrol AWD + Pedal
Electric + Pedal
Petrol + Pedal
Electric only
Petrol only
= 6 options but no option of just pedalling my bicycle. What a drag. :confused:

The 250w geared (freewheeling) but low speed limited motor means I'll never be able to use both motors together because the electric cuts out just as the petrol engine gets going. But it means I'll be able to pedal with no motor help for at least some of the time. Then it will be indeed three individual power sources on one bike, each able to be used on its own or one motor + pedalling.
Electric + Pedal
Petrol + Pedal
Electric only
Petrol only
Pedal only
= only 5 options but I can pedal unaided and coast further, which I like.


(Edited multiple times due to massive stupidity)
 
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FurryOnTheInside

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#3
Well, I thought about buying a 250W 20" wheel kit and rebuilding the hub onto a new rim with new 12g spokes (£65 extra cost).. but then I read about the common controllers often having a speed limit that is reprogrammable, or easily disabled by unplugging a connector between two of the wires as in this diagram.
Controller.jpg

So there would be no advantage in getting a controller that believes the wheel diameter to be 8" smaller than it really is...

UNLESS the hub in each of the sizes has different planetary gear ratios to optimise its performance at higher or lower WHEEL RPM with the 20" & 700c respectively.
However I read that the hubs in the different size wheels (from the same company) are very likely to be 100% IDENTICAL including the planetary ratios
because a) these are cheap motor wheels,
and b) because the fixed centers of the little planet gears would be at a different radius, meaning that the OD of the central motor and the ID of the outer shell would have to be different.. And that is very unlikely.
planetary-gear-gif1.gif


I also read about "overclocking" which I would have expected they would call "overvolting" but I call gas petrol so who cares..
I will have to see what the label on the controller says about the compatibility, but it is very possible that I can simply:
PLUG A 48v Battery STRAIGHT INTO THE CONTROLLER of my 36v kit, and unplug the speed limiter loop to get a 21mph top speed (and ~350w max power) for overtaking fast cyclists on the path in a polite way. (wshhhhh rather than BRAPPPP!P!P!)
I CAN DO IT! :coffee::D

Holy my beer batman, I might even be able to:
USE THE LCD display that comes in the 36v kit and still have an accurate battery level (voltage) indication on a 48v battery! Just have to plug it in and see. :giggle:

However I definitely need two batteries, for evenly weighted front panniers and two 48v (13S) will be heavy because they don't seem to make small ones.
I'll have to read about whether 24v batteries can be wired in series, or I can just buy a second 48v after no food for several months and just as the summer ends. :X3:


Anyway, because I love new toys, I bit the bullet and I ordered a road legal 700c front wheel! (with geared, freewheeling, brushless (250w max@36v)) kit (controller and LCD display and thumb throttle included) for £186. ($232.. ouch!)
I hope it arrives soon so I can update with real information and post a few photos! :coffee::geek:
 
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#4
Well, I thought about buying a 250W 20" wheel kit and rebuilding the hub onto a new rim with new 12g spokes (£65 extra cost).. but then I read about the common controllers often having a speed limit that is reprogrammable, or easily disabled by unplugging a connector between two of the wires as in this diagram.
View attachment 85477
So there would be no advantage in getting a controller that believes the wheel diameter to be 8" smaller than it really is...

UNLESS the hub in each of the sizes has different planetary gear ratios to optimise its performance at higher or lower WHEEL RPM with the 20" & 700c respectively.
However I read that the hubs in the different size wheels (from the same company) are very likely to be 100% IDENTICAL including the planetary ratios
because a) these are cheap motor wheels,
and b) because the fixed centers of the little planet gears would be at a different radius, meaning that the OD of the central motor and the ID of the outer shell would have to be different.. And that is very unlikely.
View attachment 85476

I also read about "overclocking" which I would have expected they would call "overvolting" but I call gas petrol so who cares..
I will have to see what the label on the controller says about the compatibility, but it is very possible that I can simply:
PLUG A 48v Battery STRAIGHT INTO THE CONTROLLER of my 36v kit, and unplug the speed limiter loop to get a 21mph top speed (and ~350w max power) for overtaking fast cyclists on the path in a polite way. (wshhhhh rather than BRAPPPP!P!P!)
I CAN DO IT! :coffee::D

Holy my beer batman, I might even be able to:
USE THE LCD display that comes in the 36v kit and still have an accurate battery level (voltage) indication on a 48v battery! Just have to plug it in and see. :giggle:

However I definitely need two batteries, for evenly weighted front panniers and two 48v (13S) will be heavy because they don't seem to make small ones.
I'll have to read about whether 24v batteries can be wired in series, or I can just buy a second 48v after no food for several months and just as the summer ends. :X3:


Anyway, because I love new toys, I bit the bullet and I ordered a road legal 700c front wheel! (with geared, freewheeling, brushless (250w max@36v)) kit (controller and LCD display and thumb throttle included) for £186. ($232.. ouch!)
I hope it arrives soon so I can update with real information and post a few photos! :coffee::geek:
What da ya mean by cogging and drag? Idk about amazon in uk but in us a 1kw wheel w/ controller is only 160 usd.
 
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#5
What da ya mean by cogging and drag? Idk about amazon in uk but in us a 1kw wheel w/ controller is only 160 usd.
The most common type of hub motor, called a "direct drive" is just like a RC aeroplane motor except it rotates around the fixed shaft instead of being fixed and rotating the shaft. This direct connection means that any time you totally de-power with throttle or the on/off switch the motor will act like a brake.
Which would be uncomfortable to have on the front wheel at up to 40mph while under 2T engine power!
And while pedalling I already have an annoying drag from the fixed rear sprocket turning the chain and half the draggy clutch in the engine.

You can tickle the throttle, allowing just a tiny bit of current, to stop the braking;
but I really wasn't keen to have to do that, especially at high speed.

So I got a hub with a freewheel inside so there's never any hub drag. :)

(It also has planetary gears which allow a higher motor RPM while the wheel turns at a moderate RPM. This should be helpful afaik since I have 700c wheels so they rotate relatively slowly for a given road speed.)

I'm still reading and learning about this ebike stuff. :coffee::geek:
Most of it goes right over my head though. :oops:


Yes the cheapest "1000W" kits are about the same sort of price here if you convert $ directly to £ one-for-one. (So actually 25% more expensive but I can't help that. Never understood money, that's why I'm poor.)

Anyway I can't seem to find hubs on their own, just wheels and most of them are direct from China so too slow plus import charges, and 99% of everything is direct drive, 99% are built into a 26" wheel, and 99% of those are REAR wheels so it just left me with only the two options for a 700c front wheel. 1000W/48v DD or 250W/36v geared.
I decided an overvolted "250W" 36v geared hub would be ideal for my needs as a 2T mbiker who just wants to stealthily slink through the more risky, public, exposed sections of the journey to my favourite camping and fishing spots, and not have the function of the 2T, gravity, or pedal power affected in any way other than the added weight.
I need the wheel to rotate at any speed up to 50-55 mph without any drag at all.
The 250W/36v hub overvolted to 48v should be around 333W sustained so not too much that heat and chewed up planetary gears would be a problem.
 
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#6
I read that "On the 36v controller, chances are very good it can handle 48v with no problem. To be sure, peek inside. If capacitors that look like little cans say 60 or 63v, go for 48v."
A little knowledge is a dangerous thing. :whistle:
 
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#7
I read that "On the 36v controller, chances are very good it can handle 48v with no problem. To be sure, peek inside. If capacitors that look like little cans say 60 or 63v, go for 48v."
A little knowledge is a dangerous thing. :whistle:
Ok but ya know u could just take a rear wheel and install it in the front? What’s the problem then except maybe your freewheel and brake thing. Just not install the cassette. Most of the kits on amazon are front/rear in the description. U just don’t install certain attachments.
 
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#8
Ok but ya know u could just take a rear wheel and install it in the front? What’s the problem then except maybe your freewheel and brake thing. Just not install the cassette. Most of the kits on amazon are front/rear in the description. U just don’t install certain attachments.
No I didn't know. I didn't get any response from the thread before I ordered a kit. :censored:
Amazon is a very expensive company to buy stuff from at least here it is so I haven't been looking there except when something pops up on a websearch.
There's a few reasons why I wouldn't expect a rear wheel to work well. Perhaps these are just my imagination? I have never seen an ebike conversion kit up close and I don't really know what I'm going to receive or how any of it works so it's going to take some time to learn. (That's half of the fun I suppose.)
Anyway the kit is already ordered so I won't be getting a rear wheel and putting it in the front. :confused:

Unrelated thought for the day:
I don't think I'll mind too much if the controller I receive is 24v/36v instead of a 36v/48v because I have seen one I'd like to try as an upgrade anyway. :) I don't know what a sine wave is but people who like them seem to be very enthusiastic about them. I can try one and see if I feel "smoother". :cool:
 
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bakaneko

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#9
Look for scooter batteries on eBay if possible in the UK. They are good starter batteries and can be as low as $30 for 150 wH @ 36V nominal. I think two of these will be good enough for your hybrid setup. Sorry, since the electric bike not much to report or issues, don't peruse these forums much. But, I will start my serial hybrid build soon. Also, I would do it exactly as you if I were to do a traditional hybrid (front wheel electric, rear gas). The way I am going to do it is serial hybrid (electric mid drive, gas generator). What voltage is the front wheel motor?

You will love the kick from the near instant torque of the electric motor. I am having so much fun just gunning it sometimes and hitting 40 mph+ in seconds and leaving cars confused as hell at the light.
 
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#10
Look for scooter batteries on eBay if possible in the UK. They are good starter batteries and can be as low as $30 for 150 wH @ 36V nominal. I think two of these will be good enough for your hybrid setup. Sorry, since the electric bike not much to report or issues, don't peruse these forums much. But, I will start my serial hybrid build soon. Also, I would do it exactly as you if I were to do a traditional hybrid (front wheel electric, rear gas). The way I am going to do it is serial hybrid (electric mid drive, gas generator). What voltage is the front wheel motor?

You will love the kick from the near instant torque of the electric motor. I am having so much fun just gunning it sometimes and hitting 40 mph+ in seconds and leaving cars confused as hell at the light.
I don't think it's even possible to mount SLA batteries. (Edit: this bit I misunderstood.. SLA wasn't mentioned. carry on.)

Haha I won't quite hit 40 with the electric motor alone. Or get a kick in the pants from the 250W/36v (333W on 48v?) front hub.
I have been enjoying my 60v/500W rear wheel drive electric moped recently though. It tops out at 24mph but nothing stops it. :cool: That has a SLA battery, weighs 75kg with rear passenger seat that transforms into a cargo rack rated for up to 75kg. The pedal assist cannot be switched off so it's a bit hilarious and mildly hazardous to manoeuvre. :ROFLMAO: Lots of laughs but it'll never pass for a bicycle. :X3:
 
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