PaulD's lightweight mid drive development

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ScooterMan101   1 MW

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Re: PaulD's lightweight mid drive development

Post by ScooterMan101 » Jun 17 2019 11:16am

Very Good, to have different plates for the different style frames . :thumb:

In regards to someone saying that 350 watts in enough ... No it is not.

I live in a Hilly area , I often am seeing over 1k watts on the Cycle Analyst when going up hills.

Add to that at my Age I have arthrits/ inflammation in my knees, ... and weak cardio vascular system.
If I did not have these conditions I would not need a e-bike in the first place ,
So
Higher power possible with higher voltage packs and A throttle are must have features .

( I already use XT 90 's on all my wiring harness that connect the battery pack to controller on my current conversion. )
My first conversion ... Sold

viewtopic.php?f=3&t=71378&p=1077497&hil ... 1#p1077497

It's 2018 already, ( now 2019 ) lets get some real , improved e-bike / e-velomobile / e-motorcycle designs .

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PaulD   100 W

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jun 18 2019 4:57pm

ScooterMan101 wrote:
Jun 17 2019 11:16am
In regards to someone saying that 350 watts in enough ... No it is not.
I think we can all agree that 350W is enough for many people. It's more that a typical pro cyclist can deliver for an hour. I totally understand that not everyone has the fitness and mobility to pedal or they want to go motorcycle/scooter speeds. This kit is not intended for them.

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Re: PaulD's lightweight mid drive development

Post by BeachRider2016 » Jun 18 2019 6:59pm

How much will they run?

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PaulD   100 W

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jun 20 2019 2:29pm

BeachRider2016 wrote:
Jun 18 2019 6:59pm
How much will they run?
We will have that posted soon. With the 378wh battery, a little under 1500 USD.

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PaulD   100 W

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jun 21 2019 12:35pm

Just a quick update to show the first few production units being assembled and the long awaited freewheels!
prod motors JUN2019.jpg
Freewheel JUN2019.jpg

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Re: PaulD's lightweight mid drive development

Post by aCeMadMod » Jun 29 2019 9:41am

Nice work. How much dose the motor wight ?

Dose it use sun gears?

What are the pad things?

What cost of setup? And watts


Thank you

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Re: PaulD's lightweight mid drive development

Post by neptronix » Jun 30 2019 12:59pm

Wow, that's a really nice looking little package!
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
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Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: PaulD's lightweight mid drive development

Post by flat tire » Jun 30 2019 1:36pm

PaulD wrote:
Jun 18 2019 4:57pm
\
I think we can all agree that 350W
No we can't. If 350w is enough for many people it's only because they can barely ride a bicycle in the first place and 15 mph is terrifying. 350w sucks ass and is very SLOW! Professional cyclists aren't fast, regular humans are barely moving at all.

Your frame of reference is probably distorted by your love and skill for pedal pushing and bike control. 350W is more than enough to make bike control the limiting factor on technical terrain but so what? I would be more willing to accept 350W if the system was a lot lighter and smaller.

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PaulD   100 W

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jun 30 2019 3:46pm

aCeMadMod wrote:
Jun 29 2019 9:41am
Nice work. How much dose the motor wight ?
Dose it use sun gears?
What are the pad things?
What cost of setup? And watts
Thank you
The motor with ASI controller, wiring as shown and mounting plates is about 4.7lbs. The battery is about 4lbs.
Yes, it uses a planetary gear reduction (12.6:1)
I think you are referring to the controller cover. This just covers and protects controller wiring.
As noted above, total price for the kit (motor, controller, battery, freewheel, bb, cranks, display) is a little under $1500. Max power is 450W.

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PaulD   100 W

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jul 01 2019 10:04pm

neptronix wrote:
Jun 30 2019 12:59pm
Wow, that's a really nice looking little package!
Thanks Neptronix! Trying to keep the wiring nice and clean is a challenge with kits that will be mounted to a wide variety of bikes.
flat tire wrote:
Jun 30 2019 1:36pm
PaulD wrote:
Jun 18 2019 4:57pm
\
I think we can all agree that 350W
No we can't. If 350w is enough for many people it's only because they can barely ride a bicycle in the first place and 15 mph is terrifying. 350w sucks ass and is very SLOW! Professional cyclists aren't fast, regular humans are barely moving at all.
Ok, I think we'll have to agree to disagree on this. :D

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Re: PaulD's lightweight mid drive development

Post by Bigwheel » Jul 01 2019 11:10pm

Very nice effort. Next time I'm down that way I'll have to check it out perhaps?

Two things,

1) It is too bad that Sempu etc. don't make an ISIS type bb. I have pretty much promised myself that I won't buy another bike without that interface, it is just plain superior to the tapered spindle and way more crank options out today.

2) No throttle? I just like to have one on board for the times when it becomes the best tool for the job.

Keep up the good work!

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jul 03 2019 6:07pm

Bigwheel wrote:
Jul 01 2019 11:10pm
Very nice effort. Next time I'm down that way I'll have to check it out perhaps?

Two things,

1) It is too bad that Sempu etc. don't make an ISIS type bb. I have pretty much promised myself that I won't buy another bike without that interface, it is just plain superior to the tapered spindle and way more crank options out today.

2) No throttle? I just like to have one on board for the times when it becomes the best tool for the job.

Keep up the good work!
Thanks Bigwheel. Let me know when you are down this way, and we'll get you on a test bike.
1) - Yes, square tapered is a bit out dated, but sufficient for most riders. We have a lot of test miles on the Sempu, and they seem to be holding up well as long as you don't let your crank bolts get loose. We are using high quality Miranda cranks which help. I abuse it regularly on the trails here, but I am not very heavy. Heavy or very aggressive riders should wait for our ISIS or Cinch solution (working on it).
2) Yep, just like a Shimano or Bosch bike. I wanted it to be Class 1 legal, but the savvy DIY'er could certainly wire up a throttle. Settings on the ASI would have to change, but it's certainly doable. If there is enough interest, I would consider a throttle version.

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Re: PaulD's lightweight mid drive development - Looking for Beta Testers

Post by justin_le » Jul 04 2019 3:57pm

PaulD wrote:
Oct 01 2018 10:41pm
Image
Hey Paul, what's that cute looking battery package I see there!? :wink:

Big kuddos on getting a custom kit design from development into what is getting very close to full production. I love seeing people succeed in making their vision pan out, it's never an easy or short road to travel.
Previously competed in the Suntrip race on a back to back tandem solar powered row/cycle trike. 550 watt solar roof, dual Grin All Axle hub motors, dual Phaserunner controllers, 12 LiGo batteries, and a whole wack of gear.

Now back in Vancouver learning to be a dad with my Big Dummy Frame (yes This One, thanks ES!) with GMAC 10T rear hub motor, Phaserunner controller, and 52V 19Ah EM3EV pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled

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PaulD   100 W

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Re: PaulD's lightweight mid drive development - Looking for Beta Testers

Post by PaulD » Jul 04 2019 11:42pm

justin_le wrote:
Jul 04 2019 3:57pm

Hey Paul, what's that cute looking battery package I see there!? :wink:
:) That's our Grin inspired potted battery pack. 10S3P LG MJ1 cells with Grin's amazing full featured LIGO bms. It's potted in super tough UL 94 V-0 polyurethane. With our stealth quick release mounts it's a pretty tidy package.
justin_le wrote:
Jul 04 2019 3:57pm
it's never an easy or short road to travel.
Thanks Justin! I definitely underestimated the challenges involved despite my past experiences with new product development. So many hurdles with procurement, and tricky technical stuff.. I'm stoked to get these into customer hands soon!

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Re: PaulD's lightweight mid drive development

Post by thepronghorn » Jul 06 2019 4:07am

On the first page you mentioned a theoretical max of 60Nm at the crank. Is that still the case?

Looks like a very clean lightweight kit! Very impressive! Can I get a quick test ride next weekend?

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PaulD   100 W

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jul 29 2019 2:02pm

Hey All,
I'm stoked to announce that our pilot production run is now available! These first pilot builds will be available for a slight discount. Feel free to ask any tech questions here. I'll start a new thread in the for-sale section. I also have various ebike parts available in my online store. Ebike cranks, Sempu bottom brackets, and some sprockets for #25 chain.

pronghorn,
I'm working on a new dyno setup to do empirical validation of the crank torque. I've been experimenting with higher phase currents for the last 6 months, so we are likely exceeding 60Nm in the production config.

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Re: PaulD's lightweight mid drive development

Post by spinningmagnets » Jul 29 2019 5:22pm

I am interested in how your custom freewheel will allow a mid drive to use the sophisticated Sempu "torque-sensing" BB...nobody else has that option....

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jul 29 2019 6:36pm

spinningmagnets wrote:
Jul 29 2019 5:22pm
I am interested in how your custom freewheel will allow a mid drive to use the sophisticated Sempu "torque-sensing" BB...nobody else has that option....
Hi Ron, the custom freewheel bolts to the Sempu T4 sensor shaft with 5 M5 screws. All of the riders power goes through this shaft and that is how the Sempu measures both right and left leg output.
The Sempu T4 is normally supplied with a rigid spider that bolts to the shaft, but this doesn't allow for a mid-drive freewheel.
The custom freewheel uses big 50mm ID bearings so it fits around the spider and it's big external bearing without forcing the chainline outboard.
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Re: PaulD's lightweight mid drive development

Post by agniusm » Jul 30 2019 12:01am

Very, very, very very nice.

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PaulD   100 W

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Re: PaulD's lightweight mid drive development

Post by PaulD » Jul 31 2019 4:27pm

agniusm wrote:
Jul 30 2019 12:01am
Very, very, very very nice.
Thanks Agniusm,
Here's a pic of the custom wire EDM ratchet ring. I'm using White Industries pawls and springs.
Edit: I forgot to mention that there are 2 offset sets of pawls, so with the 40 tooth ratchet, we get 80 points of engagement.
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ratchetring.png
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Last edited by PaulD on Jul 31 2019 9:44pm, edited 1 time in total.

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Re: PaulD's lightweight mid drive development

Post by spinningmagnets » Jul 31 2019 5:32pm

I'm using White Industries pawls and springs
All materials are not the same. I had the pleasure of meeting the owner of White Industries at one of the Interbike meets. Cheap steel "looks like" high quality steel. Not only the quality and consistency of the material can vary, but the case-hardening, and the heat-treating too...

White Industries is in it for the "long game"...high quality and low volume. They are the best available, and this was a good choice.

For a short time, I was a QA inspector for aerospace sensors at Barksdale Controls. We ran lifetime cycle-testing on samples of sensors 24/7, in the millions of cycles. Quality materials coupled with a quality design will last your lifetime.

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Re: PaulD's lightweight mid drive development

Post by briangv99 » Aug 07 2019 2:52am

Bigwheel wrote:
Jul 01 2019 11:10pm

1) It is too bad that Sempu etc. don't make an ISIS type bb. I have pretty much promised myself that I won't buy another bike without that interface, it is just plain superior to the tapered spindle and way more crank options out today.
Searching images on the web turned up an ISIS version of the Sempu, does not seem to be available for purchase yet.

https://www.aliexpress.com/item/32671603270.html
bilateral-torque-sensor-transducer-433x367.jpg
bilateral-torque-sensor-transducer-433x367.jpg (35.02 KiB) Viewed 1846 times

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PaulD   100 W

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Re: PaulD's lightweight mid drive development

Post by PaulD » Aug 07 2019 12:56pm

briangv99 wrote:
Aug 07 2019 2:52am

Searching images on the web turned up an ISIS version of the Sempu, does not seem to be available for purchase yet.
As far as I can tell, Sempu stopped making these. They were only available in 68x128mm. I have a few left over in stock that I don't need, as I have moved onto the T4, since it measure both right and left leg torque and is available in more sizes. : https://www.revelpropulsion.com/store-1 ... m-x-128mm

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Re: PaulD's lightweight mid drive development

Post by 2old » Aug 27 2019 2:55pm

I have a production kit and IMO it's a masterpiece of design and execution. The motor/controller, display and all attachments weigh slightly less than eight pounds and, since my bottom bracket and crankset weigh slightly more than two pounds, represent a net gain of less than six pounds. The battery and "cradle", which attach where the water bottle mounts on the down tube, weigh slightly more than four pounds. Also, there is an instruction manual online.

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Re: PaulD's lightweight mid drive development

Post by neptronix » Aug 27 2019 7:07pm

If you still need another tester, i have a pair of recumbents here, as well as some long 1-30% grades to scale.

Image
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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