Dave's 80:1 RC mid drive kit build log

Discussions related to motors other than hub motors.
This includes R/C motors, botttom bracket, roller and geared drives.
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Re: Dave's 80:1 RC mid drive kit build log

Post by morati » Jan 16 2018 1:29pm

Dave, no more Domino throttle?

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tangentdave   1 kW

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Jan 16 2018 2:09pm

They're real nice, but expensive (I pay $90 for each and need about 10 minutes of futzing with the solder guns and JST crimpers to make 'em work with the CA). A few guys have broken them bunny hopping and inadvertently snapping the throttle back real hard, physically breaking the tiny gear inside. I've busted a couple during get-offs. The throttle is sorta bulky and doesn't play with with other handlebar components.
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I've been using this and it is pretty nice. The action of the throttle is smooth and consistent, low profile doesn't interfere at all with brakes/shifters. Being a half twist it seems to satisfy MTBers and moto guys, cheaper to replace. The diameter of the grip is a little larger than it could be though.

I can still get the Dominos and will offer them on the website as an option. I think the half-twist works better for us.
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Re: Dave's 80:1 RC mid drive kit build log

Post by morati » Jan 16 2018 4:03pm

Would they be a direct replacement for the thumb throttles you gave with your 1st Gen. PAS units?

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Jan 16 2018 4:15pm

Yep, they use the same voltage range. Plug it in and ride.
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Re: Dave's 80:1 RC mid drive kit build log

Post by macribs » Jan 16 2018 5:39pm

may i suggest real domino throttle? like for trail riding? great feel. and searcg forum to see how to make box thst convert wire action into 5v potentio style. gwhy used to make em, look at samd website for the controller 72200 that has similar setup.

domino moto throttle <30$ electronic less <20$ and best possible throttle that will never break. electronics in the box can be inside frame and 100% water proof. such a throttle will last forever.

cheap ebike throttles don't like rain aand prone to break easy

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Re: Dave's 80:1 RC mid drive kit build log

Post by Remi812 » Jan 18 2018 10:50am

Just throwing this here because I know some people are looking for a good alternative to the heavy ISIS crankset:

Rocky Mountain made exactly what I am looking for: a freewheel that can be mounted on a RaceFace cinch crankset. It is on their new eBike called Altitude Powerplay.
What I don't know though is if the spindle is custom made and what's its length. I am guessing it is for a 73mm bottom bracket.
I'll try to stop by a Rocky Mountain dealer, see if I can order the freewheel.
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Re: Dave's 80:1 RC mid drive kit build log

Post by BCTECH » Jan 18 2018 12:24pm

it seems not available in north America to check out?

"Available in select European markets only: France, Portugal, Spain, Germany, Belgium, Netherlands, Luxemburg, Austria, Czech Republic, Slovakia, Slovenia, United Kingdom, Switzerland, & Italy."

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Jan 18 2018 4:17pm

Are you sure there's a freewheel on that Rocky crankset? I don't see the reason to have one. I'm sure there is one on the motor output.
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Re: Dave's 80:1 RC mid drive kit build log

Post by PaulD » Jan 18 2018 7:59pm

tangentdave wrote:
Jan 18 2018 4:17pm
Are you sure there's a freewheel on that Rocky crankset? I don't see the reason to have one. I'm sure there is one on the motor output.
I think it might be possible with fast response time to have a torque and cadence sensor without a freewheel. It's on my list of things to try. Right now with an ASI controller and Thun BB, there is too much of a delay that can't be tuned out (I think due to the ASI Thun filtering algorithm).
The Kranked must certainly have a freewheel since it has a throttle: http://krankedbikes.com/product/e%C2%B2v10-pro/

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Re: Dave's 80:1 RC mid drive kit build log

Post by sephespid » Jan 18 2018 9:33pm

There are different angles between crankarm and spider. and I think it is freewheel crankset.

Image
Image

and... It is.

Image

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Re: Dave's 80:1 RC mid drive kit build log

Post by ScooterMan101 » Jan 18 2018 10:25pm

Sephespid,

Can you post that bottom picture ( photo showing the inside of the Race Face Cinch Crankset with what looks like a freewheel )
on
the Design a Freewheel Crankset for Direct Mount Cranksets ... thread ?
Here
https://endless-sphere.com/forums/viewt ... 28&t=90632

Thanks
My first conversion ...

https://endless-sphere.com/forums/viewt ... 1#p1077497

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

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Jan 18 2018 10:30pm

That's a sprag clutch in there. See the key?
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Re: Dave's 80:1 RC mid drive kit build log

Post by PaulD » Jan 18 2018 11:56pm

tangentdave wrote:
Jan 18 2018 10:30pm
That's a sprag clutch in there. See the key?
Just replied in the freewheel thread. Yup, looks like a big heavy sprag ironically attached to a lightweight aluminum-spindle crankset.

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Re: Dave's 80:1 RC mid drive kit build log

Post by sephespid » Jan 19 2018 12:18am

Spider is heavy too. :twisted:

For weight problem, ISIS BB is ok. Who cares BB axle weight at 3kw/6kw machine? But external BB bearing is larger than internal BB bearing. That causes difference about load capability.

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tangentdave   1 kW

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Jan 19 2018 12:19pm

The ISIS spindles we've been using are holding up well, so are the generic cranks.

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30x62x16mm, this site lists the bearing at 218g. Now there's this to consider:

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The ISIS stuff is heavy. The sprag clutch would replace the flanged freewheel which weighs almost exactly 218g also, the sprag clutch spider would be about the same, crankset would weigh significantly less but probably require modification to fit the one-way bearing (maybe just a keyslot, maybe retaining compound would hold it on the spindle?)

The RaceFace Cinch BB's are available in varying spindle lengths:

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We need at least 150mm wide spindle to clear the 3220. This chart shows 169mm and 189mm Cinch spindles are available. Wonder if a CSK one-way bearing could be held between the BB cup and crank...I bet we might save 500g over the current ISIS setup.
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Re: Dave's 80:1 RC mid drive kit build log

Post by 12-C » Jan 19 2018 1:15pm

Personally I don't mind some weight, there is a reason that tanks and humvees heavy :lol:

But I'm all for progress! :D

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Re: Dave's 80:1 RC mid drive kit build log

Post by ScooterMan101 » Jan 19 2018 2:09pm

500 g is a little over a pound, that is a huge weight savings when talking about just one/two piece component of a bike.

I thought Shimano and the rest went with bearings on the outside of the BB shell were making improvements as well with having the bearing load wider than Square taper BB's and ISIS BB's .

With the extra torque delivered to that area when using a motor, I would think we want that outer bearing system as well.
My first conversion ...

https://endless-sphere.com/forums/viewt ... 1#p1077497

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

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Jan 19 2018 4:21pm

Wider bearing spacing = better
Spindle mounted freewheel > crank mounted freewheel

I've also been thinking about torque sensing PAS for a while. If, at the motor, we use a freewheel-on-a-freewheel, we can separate the pedal chain from the motor chain for torque measurement. The pedal sprocket runs up to a FW on the motor, which is mounted onto the output FW of the motor. The motor output runs back to the crankset and spins a bearing mounted spider with the derailleur front ring mounted to it (we want to run the bike driveline as designed, so always from the BB). The crankset could be an unaltered RaceFace Cinch style with the bearing mounted inboard of the pedal spider. We'd have a big bearing(s) like that CSK series we're talking about, so it' look similar, but instead would just spin on the spindle, not attached to the pedal spider. The pedal forces would get to the rear wheel by turning the motor freewheel, which would turn the BB bearing spider.

Now, if Grin would hurry up and finish re-designing the BeamTS so I can get one and see why this don't work.

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Re: Dave's 80:1 RC mid drive kit build log

Post by cr0m08 » Jan 19 2018 7:41pm

I actually like the current generic cranks, hugely, because they are easy to have them shortened. Due to knee issues and a severe hip injury, I find it very difficult to either spin cranks or crank hard @170mm length so I don't really want to see this option disappear. My LBS was able to shorten and steel thread (helicoil) these cranks down to 143mm. As we are riding with such high power systems (even the 3210) the short cranks have multiple advantages. Higher cadence spinning is much easier, not so much offset of the feet with cranks parallel to ground and much more ground clearance if a crank is on downstroke.
I realise this probably does not suit many people, but I think many would be surprised at just how good it can be with short cranks.
Dave has given me back a level of ride strength and speed I just could not achieve since that hip injury, the steel hip insert is permanent. You rock Dave!
As an aside, I would love to see a straight through peg system (moto style) like the downhill snow bike conversion kits (or the Stealth Hurricane). On a 3220 would be an absolute hoot off road of course! Don't know how much I would use it, but damn it would be fun!
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2015 Nukeproof Pulse, 3220/HV160 @12S V1.5, 26x2.8" Nextie 50mm wheel set
2006 KeeWee Cromo Eight, 3210/HV80 @12S V1.5, 24x3" wheel set.
1998 Marin B17, Mac 10T @18S in 19" Kris Holme Trials rims, 19x2.5" wheel set (still to finish)
part build Basman 346, QS205 hub motor @12S in 24x3" wheel set. (still to finish)

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Re: Dave's 80:1 RC mid drive kit build log

Post by ScooterMan101 » Jan 20 2018 12:29pm

crOm, 160 mm crank arms are easily found now so 175 down to 160 should cover most everyone, even good and very light weight carbon ones are available in 160 mm length.

Dave , I am getting more convinced that we ( anyone who wants to sell a product for mid-drive e-bikers ) , that we should just develop/design our own cranksets using design clues from the Race Face Cinch and other Direct Mount Cranksets from other Mgf's / AKA 3 piece cranksets, in the following way.

1 ) Design around the Typical Outer Bearings like
Shimano 24 mm into threaded BSA
or
Sram GPX Outer Bearings 24mm or 30 mm into threaded BSA

2) Copy the Design of the Race Face Spindle and Crank arm interface in both 24mm or 30 mm spindle so that every one can use it on their bike .

3 ) And this is one of the more important items, Design the Crank Arms so as to have enough room to fit a freewheel and 2 chainrings. ( one chainring motor one or even two chainrings driving the rear cassette )

4) Machine the Spindle/Drive side Crankarm longer so that either the Chainrings or the Freewheel can slide directly onto the Spindle, or if spiders are involved so as to operate the freewheel and one chainring and the other chainring bolted to the crank arm.
( not ever seeing and operating a freewheel crankset I am not sure which should be directly slidded onto the Spindle ).

By Designing Spindles for mid-drive e-bikes as we all know it needs to be a little longer than typical in order to have enough room for the freewheel and both chainrings , with the inner chainring located to have the proper chainline , and for the higher power systems I am understanding that we should be using the largest 5 cogs of the cassette in order to have enough chain in contact with enough teeth.

Also we no not need to have crank arms that bow outward as they do on a standard bike with 68mm-73mm shell. Since the Spindle is now longer the crank arms can be straight and still be able to fit a riders hip / feet position that is needed .
My first conversion ...

https://endless-sphere.com/forums/viewt ... 1#p1077497

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

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Re: Dave's 80:1 RC mid drive kit build log

Post by Leeleeducati » Jan 21 2018 11:34am

Hey Dave,

In getting my chain line ready to accept the Ascent V2.0 I have a few questions;

1) What is the thickness of the mounting plate? See the first picture, I have a temp. 4mm spacer as a place holder, but need to know exact. Left to right you can see the frame, then the PF to threaded adapter, then the spacer then the bottom bracket cup.

2) Would an FSA Platinum BB (100mm x 148mm) give enough clearance, not sure what you use in your kit? With the Echos I get some good clearance between the crank arms (7.5" to 7.75" -ish).

Let me know and thanks!
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Re: Dave's 80:1 RC mid drive kit build log

Post by Ecyclist » Jan 21 2018 12:20pm

tangentdave wrote:
Jan 15 2018 12:51pm
I am curious about the power draw of the Cyclone and Bafang kits, if anybody has one with a CA, please share the full-speed power draw when the chain isn't connected to the rear. I think 200W loss at 12,000RPM is fine.
-dave
I don't have Cyclone or Bafang kit and I don't know if that will help but I measured my setup with my Hypocycloid powerd by 6374 motor (3200W and 125Kv).
Motor only 45W
Motor with transmission 65W
Motor with transmission running rear wheel off the ground 85W
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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Jan 21 2018 6:40pm

Each mounting plate is effectively a 2.35mm thick spacer. The plates are 1/4" thick but I cut a pocket at the BB so the added width needed at the spindle is 2.35mm per side. Can you measure the outside face to outside face of the PF adapters? This would be the effective BB width I need to space the plates to (with the spacers). I'm sure the Echo cranks give enough clearance; middle chainline to outside motor is 150mm, the motor chainline is 20mm outboard of the BB face.

Ecyclist, 20W for 4600RPM is pretty f'n ridiculous. I've been following your thread, nice work. I've put some big bearings in the Tangent, they may be overkill, but I gotta flog this chassis
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Steel frame, high pivot, progressive smashness. The frame is a Peregrine (http://www.peregrineindustry.com/), Maintou Dorado forks, Saint stoppers, 26" wheels, Chris King hubs. Bike is setup single speed, 16/24t motor/crank so 400RPM at the crankset and the wheel (32t/32t crank/wheel), 31mph and will lift the front at any point on the way there. The frame is stout, look at the wide stance of the swingarms. No noticeable flex at 7.5kW. Waiting for Seattle to finish draining then trail smash.
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Re: Dave's 80:1 RC mid drive kit build log

Post by Leeleeducati » Jan 21 2018 7:14pm

Here you go... call it 96.25 +/- .25 face to face with the PF adapters.
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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Jan 21 2018 10:52pm

Roger. This is PF92 with adapters? Can you link to the exact adapters installed?
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