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2019 YT-TUES Downhill Electrification Custom Build

e-Sprocket

1 mW
Joined
May 14, 2019
Messages
11
Ive been playing around with e-bikes for the last few years and have ridden many good ones and not so good ones. For this build I wanted to build a high end e-bike with the best components. Decided that I would start with an amazing bike and a Mini Cyclone as my power plant. The reason I chose this motor is because of it low weight, the big one is just to heavy for my application. Below is the process I went trough to electrify this bike.

Things to buy:
1. 2019 YT-TUES form YT-Industries. This is a full carbon downhill race bike and is considered one of the best DH bikes made.
2. Mini Cyclone motor from Luna. Ive used this motor before and was quite happy with the power output.
3. Purchased a ASI controller directly from Accelerated Systems. These controllers are very well built and you can purchase the developers package to program them yourself. Much better than the Kelly controllers I’ve tried in the past.
4. ORO mini twist throttle for the power control. I don’t like pedal assist and rather have a throttle to apply the power.

Time to build:
1. Stare at the bike for some time to figure out how to mount the motor and controller with minimal weight and bulky mounts.
2. Take a bunch of measurements of the frame and bottom bracket. I had a friend help me 3D scan the geometry using a Faro arm. This gave me a 3D image of the down tube and basic dimensions of the bike to start with.
3. Created a sketch of the bottom bracket using Fusion 360. (Fusion 360 is a CAD program for mechanical engineering, amazing tool, you can build anything with it.)
4. Measured and replicated the Mini Cyclone in my Fusion 360 software so that I can have a 3D model of the motor to work with.
5. Sketched out the ISCG mount to use as the main mount point for the drive plate. Lucky that the technical drawings for the ISCG mount were really available online.
6. Created all the 3D CAD drawings for the motor mounts, drive plate, and down tube mount.
7. 3D printed all the parts using my home made FT5 printer.
8. Test fit everything onto the bike to check clearance and fitment.
9. Make some minor adjustments to my 3D files and reprint all the parts.
10. Final test fit of all the parts
11. Make a custom adapter to thread into my mid drive freewheel for the main chainrings. This was made to adapt the RaceFace direct mount style crankset to the threaded freewheel chainring adapter. (Thank you Jonny V For the machine work.)
12. CNC cut the main drive plate from a kevlar/carbon composite 5mm thick sheet. (Also a Jonny V job)
13. 3D print the down tube mount for axial load and motor stabilization. (This part doesn’t hold that much force so its made from 3D printed PLA).
14. Program the ASI controller and fine tune some parameters.
15. Final install of all the parts
16. Test drive. I hit 40 MPH! Not bad for a mini cyclone motor.

Weight
Total weight of all the parts, controllers motors etc. approximately 8Lbs.
Total weight of the bike 43.8 LBS, that’s pretty cool and it still feels very snappy and nimble over jumps.

Next steps
1. Having some minor issues with the chain tensioner. Redesigning one in my 3D software with a chain guide built in.
2. Front chain cover to keep out the sticks and weeds that get sucked up into the motor.
 
Photos here. https://electricbike.com/forum/forum/main-forum/diy-discussion/86760-2019-yt-tues-downhill-electrification-cusom-build
 
ca583c260b63449d47497cb3d82d3f81.jpg



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What battery you have? Backpack? How many cells is it? How heavy do you find it?
 
Tommm said:
What battery you have? Backpack? How many cells is it? How heavy do you find it?

You got it with the backpack. It’s an additional 10 lbs of battery in my evoc backpack. I run a 14s 7P custom built pack made with Tesla 18650’s. That comes out to 98 cells at 51.8 volts nominal.

I’m building a new pack, thinking possibly 17s that would put me at 62.9v nominal. Im a big fan of higher voltage. Less heat.


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e-Sprocket said:
Tommm said:
What battery you have? Backpack? How many cells is it? How heavy do you find it?

You got it with the backpack. It’s an additional 10 lbs of battery in my evoc backpack. I run a 14s 7P custom built pack made with Tesla 18650’s. That comes out to 98 cells at 51.8 volts nominal.

I’m building a new pack, thinking possibly 17s that would put me at 62.9v nominal. Im a big fan of higher voltage. Less heat.


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How many cells will the next battery be? How long rides do you go on and how uncomfortable is it?


For sure, go as high as the motor efficiency will let you. I build 72v on everything 17 is a bit odd so you might get a poor selection of bms/chargers.
 
e-Sprocket said:
I’m building a new pack, thinking possibly 17s that would put me at 62.9v nominal. Im a big fan of higher voltage. Less heat.

That's a pretty misleading oversimplification. Note that with higher voltage, motor unloaded speed increases. The larger the difference between unloaded speed and road speed, the lower the efficiency (so heat increases). If you turn up the speed so the motor operates at higher efficiency, current quickly comes back up to where it was in the lower voltage system, and resistive heat is therefore the same (but power consumption and magnetic heating are higher).

You can use a slower wind motor, so higher voltage doesn't result in higher RPM. But slower winds have more resistance, so you end up with... the same amount of heat.

What raising voltage definitely does is make your electronic components less reliable and more expensive, like for like.

The real reason to raise or lower system voltage is to match a given motor's speed and power to the demands of a specific application. At any specific combination of speed and power that is attainable in a specific vehicle with a lower voltage, raising voltage generally has no positive effect on efficiency or heat generation. It can make it worse, though.
 
Tommm said:
e-Sprocket said:
Tommm said:
What battery you have? Backpack? How many cells is it? How heavy do you find it?

You got it with the backpack. It’s an additional 10 lbs of battery in my evoc backpack. I run a 14s 7P custom built pack made with Tesla 18650’s. That comes out to 98 cells at 51.8 volts nominal.

I’m building a new pack, thinking possibly 17s that would put me at 62.9v nominal. Im a big fan of higher voltage. Less heat.


Sent from my iPhone using Tapatalk

How many cells will the next battery be? How long rides do you go on and how uncomfortable is it?


For sure, go as high as the motor efficiency will let you. I build 72v on everything 17 is a bit odd so you might get a poor selection of bms/chargers.

I have a charger that can change anything up to 24s so no problem with charging. As for the BMS, going to make one myself. I don’t know how many cells yet, just kicking around the idea for now.

The backpack solution works very well and is more comfortable that one would think. I don’t even notice the extra weight as long as you have a good backpack that tightly molds to your body. I do rides that last between 1-2 hours depending on terrain. Not all that is under power, I use man power and assist with the electric part.


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Chalo said:
e-Sprocket said:
I’m building a new pack, thinking possibly 17s that would put me at 62.9v nominal. Im a big fan of higher voltage. Less heat.

That's a pretty misleading oversimplification. Note that with higher voltage, motor unloaded speed increases. The larger the difference between unloaded speed and road speed, the lower the efficiency (so heat increases). If you turn up the speed so the motor operates at higher efficiency, current quickly comes back up to where it was in the lower voltage system, and resistive heat is therefore the same (but power consumption and magnetic heating are higher).

You can use a slower wind motor, so higher voltage doesn't result in higher RPM. But slower winds have more resistance, so you end up with... the same amount of heat.

What raising voltage definitely does is make your electronic components less reliable and more expensive, like for like.

The real reason to raise or lower system voltage is to match a given motor's speed and power to the demands of a specific application. At any specific combination of speed and power that is attainable in a specific vehicle with a lower voltage, raising voltage generally has no positive effect on efficiency or heat generation. It can make it worse, though.

As long as the items are rated for that voltage range, components won’t be compromised and lose reliability. I agree that the Mini Cyclone would prob not like the higher voltage and the ASI controller is only rated to about 90v. I don’t like to bog down my motors when running a higher voltage so gearing needs to be adjusted for the added RPM.

I was going to use a different motor that is specifically built for higher voltage and lower RPM. It requires a custom controller that we are also testing. This is all in the works and I’ll post the data when we get closer to having something working. It’s a totally different build.

This build was made with a simple generic motor and parts from Luna for fun.

Thanks for the feedback.


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Nice build 👍. I’m a big fan of backpack batteries as well. I’ve been using it for the past 3yrs, so stealthy!
A big bonus is if you fall, the cable just disconnected the bike.
How is the noise level on the mini cyclone with the asc controller?
One of my bikes, I used my mini cyclone with stock controller it was quite loud, ended up switched to a tsdz tongsen. I’m itching to use that motor on a fat frame.
 
Please keep me posted, by PM , since I will probably loose track of this thread .

What do you think the cost of this new higher voltage and lower RPM ( Kv ) system with all components will cost ?

I have a F.S. Santa Cruz Bike that I am wanting to put a high power mid-drive on. It has the usual dog leg shape on the lower downtube near the BB.

Thanks


e-Sprocket said:
I was going to use a different motor that is specifically built for higher voltage and lower RPM. It requires a custom controller that we are also testing. This is all in the works and I’ll post the data when we get closer to having something working. It’s a totally different build.

Sent from my iPhone using Tapatalk
 
Great Conversion

Looks like someone finally made a freewheel for a more modern style of Crankset / BB

What is the make and model of the Crankset and BB ?

The YT has a BB30 or other or BSA Threaded on the Frame ?
 
How did you end up mounting the battery? I am doing a similar conversion but with a TSDZ2 and a 2016 Tues CF that I'm not finished with yet.
rGhhNbq.jpg


The motor, wiring and display are all done but haven't got the battery in yet. I'm very slowly designing a battery pack that fits into the triangle on the frame right now (a 28 cell 14s2p using samsung 18650s). The 3d printed prototype fits pretty well with the BMS and all the cells. I just need to get around to figuring out the final attachment points and an nice aesthetic / waterproof cover. The pack conforms pretty well to the curvature of the 2016 L frame though, I was surprised I could get it to fit.
HmZtQOg.png


If anyone else tries to do this with a TSDZ2, you need the eccentric bottom bracket adapters and the 83mm TSDZ2 axle extension kit from Eco-ebike. That extension is not super easy to install but if you make a nice tapping jig to hold it all straight, it isn't too bad. Also, FYI, I looked at a lot of different downhill bikes and very few had thin enough frames around the BB to fit the TSDZ2. Most aluminum frames work (like a Banshee Legend or a Tues AL) but very few CF frames will work. Lastly, the TSDZ2 reduces the ground clearance a small amount (not actually that much though compared to the stock chainring on the stock bike).
 
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