AFT or LR or GNG which is better?

[slowhands]

I'm curious why belt reduction is used for first stage. Is it cheaper? Lighter? Quieter? What are the pluses and minuses? Why not HD25 chain, or 35 chain, or 219 chain, or T8 chain? What were the tradeoffs?

This is not a criticism, just curiosity about the strengths and weaknesses of the various options. I see the 219 is used on the LR big block, better tensile strength? I seem to remember the Aerovironment Charger used a belt primary and 25 chain to the rear hub, but that was lower power I'm sure. Why choose which size?

 

[markz]

AFT has an interesting price chart.



"They" did a study, the more choices a person has, the less likely they buy.
Its a toss up between the two for me.
I'd probably just go with the simple choice of L.R. for $1000, and a internally geared hub on the rear wheel.

 

[spinningmagnets]

I'm curious why belt reduction is used for first stage

Its quieter. If you want a 30:1 reduction in a single stage, and you want a minimum of 11T on the drive sprocket, that would entail finding and fitting an 11T: 333T sprocket combo. Dividing it into two stages with a jackshaft in the middle is a common solution that has been proven to work well, using easier-to-source sprockets/pulleys. Once two stages is chosen, the first stage experiences more RPMs and less torque, while the second stage experiences more torque and fewer RPMs.

All-belt and all-chain dual-reduction drives have been tried. On an all-belt drive, belt slippage on the second stage limited the power the drive was capable of. On an all-chain drive the primary was much louder than the secondary.

There are AFT customers who are happy with their purchase, and from reading their posts, DO NOT get the internal controller, and DO get the cooling fins.

 

[Lenk42602]

AFT.

 

[Nathan]

I'd probably just go with the simple choice of L.R. for $1000,

Hope you don't mind waiting ! as it seems minimum is 2-3 months before he ships a kit, which is quite tardy considering pretty much nearly every other kit will be at your door in less then 1 month. Sheeze in 3 months time by the time you order their could be so many new and better kits come out and if you have locked in an order well you are stuck with it....

 

[macribs]

What's so good about that kit ? [Tangent Drive that is] The continuous power rating is only 1350W continuous ? Ok 4000W peak sounds good but I don't think any normal bicycle chain and derailuers can handle more then 2-3kw anyway without destroying itself very quickly.

ok the weight might be lot less then the bigger motor GNG /LR kits but I don't think it would be much less 0.5kg then the Cyclone type kits. And where that weight is less is on the small motor thermal mass and Tiny ESC .Which is exactly where you do not want to loose the weight as you have no thermal mass to absorb the high loads of an ebike. Hence rapid motor overheat and ESC failures that are not a proper ebike controller .

Well first of all tangent uses Astro motors. Those motors have proven themself times and times again. Secondly because of the reduction the motor operate in the most efficient area more of the time. Less stress and less heat. Also Astro motors with axle mounted cooling fan makes for easy and effective cooling.

How well the reduction drive unit holds up is anyones guess at the moment by Tangent has driven hard without failure. The concept of his reduction unit seems to be widely known and well tested by others - what metal and hardening he uses I don't know but several ES members run his units now and I have yet to see anyone reporting problems.
If more power is needed why not run the Tangent drive with Astro 3220 rather then 3215? Twice the power.....

I don't think Tangent's drive unit should be ruled out of the competition here.

 

[jk1]

Well first of all tangent uses Astro motors. Those motors have proven themselves times and times again. Secondly because of the reduction the motor operate in the most efficient area more of the time. Less stress and less heat. Also Astro motors with axle mounted cooling fan makes for easy and effective cooling.

The ASTRO motor power ratings are rated for use in an aeroplane with high cooling air flow , so their continuous power rating on the ground on an ebike with a lot lower air cooling effect is a lot lower. Also the first people who have used it seem to match this as they say the motor heats up very quickly. Hence tangent dave list the continuous power a lot lower at only 1350w

https://endless-sphere.com/forums/viewtopic.php?f=31&t=70098&start=50

. Not exactly quiet even with the soft mount, but powerful, and lighter and more compact than any of the competition. Powering up 20% grade hills doesn't even stress it. It's possible to get the controller and motor both pretty hot by pegging the throttle,

 

[jk1]

Their is some more discussion on why an ESC is not a good idea to use as an ebike controller here:

https://endless-sphere.com/forums/viewtopic.php?f=2&t=23882

by madin88 » Fri May 30, 2014 3:28 am



mattetjus wrote:Since an airplane BLDC-motor can be assumed to need its maximum torque at its (near to) maximum RPM (the propeller of the aircraft turns easy at low RPM and pushed more air the faster it spins), such RC ESCs are built accordingly, not expecting high currents at lower speed. on a bike without extra protection this means that the ESC will try to run at maximum load (eg 5kW) from start and hence kills itself due to too large currents.


very good explaination. this is the main reason why RC ESC are not a good choice for our ebike usage.

 

[macribs]

Well first of all tangent uses Astro motors. Those motors have proven themselves times and times again. Secondly because of the reduction the motor operate in the most efficient area more of the time. Less stress and less heat. Also Astro motors with axle mounted cooling fan makes for easy and effective cooling.

The ASTRO motor power ratings are rated for use in an aeroplane with high cooling air flow , so their continuous power rating on the ground on an ebike with a lot lower air cooling effect is a lot lower. Also the first people who have used it seem to match this as they say the motor heats up very quickly. Hence tangent dave list the continuous power a lot lower at only 1350w

You are partly right - but notice that i wrote "Astro motor with axle mounted cooling fan". Matt has used Astros with cooling fans in his builds and those fans are very effective cooling the motors. The faster the motor spins the faster the fans RPM and more air flow around motor. And with the added cooling fan you can spend more time closer to the max peak performance without risking meltdown.

The continuous power and even peak power is not just a show off number only usable in RC air crafts, because of the high power from those Astros those motors will propel you and your ride so quickly up to high speed you will in most real world usage be forced to roll back on the throttle way sooner then the heat will become a problem. And with a fan mounted high air flow will reduce the heat build up and help with cooling.

 

[Ralith]

RC ESCs may not be designed for ebike use, but Castle Creations controllers such as the HV80 have been in use for years and nobody seems to have any trouble with them. As far as heat dissipation is concerned, the Tangent kit gives the Astro motor quite a bit more heat sinking than it would have in RC installation, and, as others have pointed out, if you're drawing multiple kilowatts you're going plenty fast. I have no trouble whatsoever with sustained draws above 2kW, and that's with a sealed motor.

The Tangent drive looks very interesting. Very high quality and very lightweight.

It looks like the "bare bones" kit with the mounting brackets, reduction gear-set, and freewheel is $700? And the "ready to run" version with Castle Creations HV80 ESC, Astro 3210 motor, and V3 Cycle Analyst added is $1800?

I would love to test - ride one, I'm sure it would perform well. What voltage are you running? 12S, 13S, or can the HV80 handle 14S?

Those prices look accurate to me. I'm running 12s on my Tangent kit, which is what the HV80 is rated for. I'm not sure if it can handle higher voltages at all; I certainly wouldn't want to test it on my unit. The controller is probably the one thing I'd change; the HV80 is being pushed to its very limits in both current and voltage, and a bit of breathing room would be nice. Then again, it's super compact, lightweight, and reliable, and there aren't a lot of other options at this power level. A HV110 wouldn't go amiss.

I was also looking to buy the LR kit and then i saw all the problems people were having on the thread and then when i added up all the costs its not as cheap as it seems as others have mentioned their is no controller and no throttle as well !

but what worried me even more was that since he doesn't sell the controller as part of the kit, its up to you to sort out the wiring and compatibility to motor. This is a problem if you have programmable controller and you need to match the current limits and setting to the motor. I could easily see the situation that if had a motor melt down it would always be the controllers fault.. because its not a complete system, its just a motor. I think its better to buy both from the same place so they MATCH each other and then no one can pass the buck and you have 1 warranty from 1 person for the whole system and how its setup is safer.

I ended up buying the cyclone 48v 1680w with the kelly, and i am very happy with the power ! it peaks at 3000w,

This tangent kit looks interesting but very pricey ! wow $1800 usd i could buy more then 3 of my kits

The cyclone kit's motor alone weighs almost 10 pounds according to their site, which is more than the entire tangent kit, gearbox and motor and mounting hardware and all.

Are u sure 10 pounds ? I have my kit off the bike on the bench and i just measured the weight as it always felt light but i never measured it. On the Tangent website photo of the kit on the weight scales, it just has the motor, gearbox, freewheel and mounting hardware and esc. weight it says 3.5kgs and that's without the bashguard which is extra.

And now i measured my cyclone kit the same parts, motor , gearbox and freewheels and BB mount and controller and its 3.9 kg or 8.47 pounds. 10 pounds must be with the chainwheels and BB. So the difference is 0.4kg or 0.88 pounds. With all the money i saved compared to the tangent i would rather spend that and get a new lighter bike ! or the best new high capacity battery cells and i will save a lot more then 0.8 pounds

The cyclone website is a terrible mess, so perhaps I'm looking at the wrong thing, but they explicitly advertise a "4.1Kg Light weight BLDC geared Motor !!" on at least one page. That's for a system rated at most 3kW. Perhaps you got a lower-power kit and are overdriving it?

The Tangent kit does not presently include a bashguard. It seems to be a structural consideration for an early prototype that proved unnecessary.

I agree that the LR kit seems pretty dicey. The Tangent kit is a work of art, but I have to agree that the cyclone kit does provide a nice price point. Seems like the AFT kit costs just as much as a Tangent, though.

 

[John Bozi]

Stuff always changes from design to exchange rates.

I have waited 3 months so far but am somewhere in the to be shipped queue. Apart from the AUD to USD plunge annoying me (not ebike builders fault) who cares if you wait. The design has improved for the LR again, so I am glad it took that long.

You lock your money in to something from Mike and you know it won't be el chineso.

I paid a deposit to be put in the queue and then I could search for a bike, batteries etc. It's been great working with Mike as busy as he is.

Tangent was very interested but the sound is scary and doubt it would sustain continuous climbing like the big block can.

AFT I was very close but at the time $3k was much higher than the LR. Now with the dollar exchange things start changing but still I wanted a set up that the maximum possible even if I don't know how to harness it yet. In time I think the big block is the best choice as it's not a first time kind of bike, it's a wait and work out the best you can get kind of set up.

If you are impatient and have hard headed views about what is possible than stick to lower power. Some people are happy to push the envelope and believe that there is a way forward with more power even if for now the every day bicycle drive train is not strong enough.

 

[Nathan]

The cyclone website is a terrible mess, so perhaps I'm looking at the wrong thing, but they explicitly advertise a "4.1Kg Light weight BLDC geared Motor !!" on at least one page. That's for a system rated at most 3kW. Perhaps you got a lower-power kit and are overdriving it?

I just measured my cyclone motor and gearbox and its not 4.1kg not sure what that is for ? photo attached and its 3.07kg for the motor and gearbox.

AFT I was very close but at the time $3k was much higher than the LR.

What AFT kit was $3000 ? the closest one I can see on their website to the LR kit is around $1800 AUD not $3000AUD ? And like others have mentioned it is a complete kit as it comes with a Kelly controller and throttle, wipperman chain . the LR doesn't even come with ANY controller/throttle as standard add delivery to all these missing parts and costs add up...
Also i am pretty sure the AFT kit comes pre assembled, controller mounted and wires connected like most other kits , unlike the LR which is a box of parts and no wiring done let alone controller mounted.... if you factor those difference in and how weak the AUD-USD price is similar to the LR, but a lot lighter ALU brackets and more compact gear reduction then the LR.

 

[John Bozi]

IF you get the all the upgrades + GST the quote I got was over $3000 AU.

I won't post my invoice as I said I wouldn't. But here is a break down of relevant parts:

-OFFROAD ONLY 1680w EXTREME KIT with 35A C/ 100A Peak Kelly = $1399 --EMAX upgrade pack add $449 for 6 upgrades below:

1)Gearbox Grease to oil conversion 2)AFT custom low friction oil with high concentration Mos2 NANO particles. “Moly Gear 3)Oil Additive considerably reduces wear and lowers peak temperatures. 4)AFT chain guide upgrade, 5) 3 x AFT hybrid ceramic gearbox bearings, 6) 2 X AFT Stage 1 Motor hybrid ceramic bearings -PRO KIT = Includes our heavy duty 6mm laser cut mounting kit , DICTA ur heavy duty 6mm laser cut mounting kit and ACS crossfire crank freewheel.

-EXTREME KIT = Includes PRO kit + ACS 13T motor freewheel, ACS motor Chain,

48T chain wheel, NEW stronger double cross brace mount and cooling fins

- Black anodised finish all laser cut parts add $169

- Stage 2 Ceramic motor bearings ABEC5, NON contact seal less drag then EMAX ceramic. Add $149 -Stage 2 oil conversion $129

- Stage 3 Magnet filter $75

- Cooling fins 169 Stg2= $249

- Noise reduction chain guard $99

- Noise reduction gearbox shroud = $139

- Excess pro crank freewheel upgrade Add $29

- Excess pro Motor 13T upgrade add $29

- Lightened drilled steel hduty chain wheel – Add $39

- motor tensioner upgrade $25

- Alignment and Tension tools = $35

-Wipperman 7R8 Strongest 3/32 chain on the market instead of ACS = $49

- Chainring Hduty bash guard = $54

- ISIS BB and cranks 68-73=$99

-gearbox refill purge kit = $59

- AFT custom ISIS large bore bottom bracket removal tool.$49

-CAv3 Thermistor supply and install into motor windings ( @EMAX upgrade) =$62

( Please advise down tube circumference for our frame clamps= 153C 48.7Dia mm , Chainwheels 48T motor and 40 T 32T bike And BB width and type = 68mm )

Yes it's a complete kit.

Even if the big block costs me $2000 AU with shipping and terrible exchange rates, a conctroller and throttle does not get me up to the $3k. It is getting there if I kept doing upgrades to all the freewheels though....

 

[Nathan]

That's a big shopping list did you select every single upgrade they sell that would have been one hell of a kit ! did you need all of those as the LR kit doesn't come with lots of those things ???
Ahh so you got the EMAX with ABEC5 ceramic bearings in the motor and gearbox ? They seem to be quite expensive but have extremely low rolling resistance and extremely long life and I would imagine their is quite some time involved to open the motor and gearbox to install.
Also you got a wipperman chain and CA3 temp sensor and some other special tools ?? and none of those things come in the LR kit.
So I don't think you are comparing like with like if you compare a kit that comes with cheap chinese bearings and hasn't been opened with one that has.
Also I think you are in AUSTRALIA? so bummer you need to pay 10% GST whereas as everyone else doesn't

 

[John Bozi]

I didn't buy it, I was on the verge of it.

A lot of the upgrades are essential for a small motor to deal with continuous steep climbing. Hence big block even if I run it at lower power, I have leg room to grow. Hopefully I ll rarely need to open the 3kw motor, much nicer to deal with external parts in my opinion than oils etc.

Yes in Australia we are dammed if we do GST and dammed if we don't as the AUD has tumbled.

 

[Nathan]

I didn't buy it, I was on the verge of it.

A lot of the upgrades are essential for a small motor to deal with continuous steep climbing. Hence big block even if I run it at lower power, I have leg room to grow. Hopefully I ll rarely need to open the 3kw motor, much nicer to deal with external parts in my opinion than oils etc.

That's assuming a large motor solves all your problems , it doesn't it only solves one and that is heat. Ceramic bearings and wipperman chain have nothing to do with heat load improvement but instead increase in quality and service life.

But if you have them I think ceramic bearings have a lot longer life then steel and also a lot less drag.
Because of the properties of ceramics, a hybrid bearing's service life can be up to 10 times that of a standard steel bearing, reducing the need for maintenance on your machine as well as the costly interruptions in production.
http://machinedesign.com/bearings/ceramic-bearings-save-energy-extend-life
The flywheel drive motor drew 10 to 12% less current when running ceramic bearings than when metal-containing bearings were used.
http://www.skf.com/us/products/mrc/hybrid-ceramic-ball-bearings/index.html
Increase service life

And the wipperman german chain is known to be very high quality steel so it will also have a lot longer life.