Vetting the XYD-16 (24V 450w DC Brush Motor)

Vetting the XYD-16 24V 450w DC Brush Motor


While hunting for a replacement, I found the manufactures specs of this motor.

View attachment 1
Most surprising was that this 450w "rated" motor is capable of 750w output!
No, not by over volting, simply by removing the current limitation.
Rated 450w with a 26A controller.
70A controller allows 750w output.

Why the 450w rating ... ?
Regulated to prevent damaging heat!
But also, it places maximum motor output right near top speed ... where it is needed, for continuous cruising.

Hunting with the ebike.ca /simulator, I found a motor that matches the XYD-16 motor, at 24V with 13T motor sprocket mod, nearly identically.
The Nine Continents 3004

Proven out by comparing to 25A controller


Much easier to do a direct comparison


At 20mph+, torque, acceleration, efficiency etc. are nearly identical.
Motor is designed for cruising = ideal commuter.
Not ideal for hills, stop and go traffic etc.
You could regear to match your hills ... ?
But I recommend as more of a cruiser than a climber.

Of course ... with pedal assist at lower speeds, performance can be surprisingly good!

Manufactures specs in PDF
http://www.cytron.com.my/usr_attachment/XYD-16 Drawings.pdf
http://donar.messe.de/exhibitor/hannovermesse/2014/M619072/xyd-16-series-eng-296356.pdf

The Unite MY1018z motor seems to be nearly identical to the XYD-16 motor.

The My1018z was the predecessor, replaced in 2009 Currie applications, differing in that it uses straight cut gears in the gear reduction component.
By replacing the straight cut gears with helical gears, the motor became much quieter.

However there are advantages to the MY1018z!
1. straight cut gears are more durable
2. straight cut gears allow 100% durability in CW and CCW directions. Works just fine in forward and reverse directions, mobility scooter, small 3-4 wheel applications etc.
3. direct and extended testing demonstrates a slight speed and power advantage ~5%+

Well 25.9V w/13T mod numbers look right.
So, 33.3V w/13T mod supplies reasonable assist to 30mph, will even push near 30mph motor only ... with an aerodynamic tuck!



But I am more inclined to use a MY1018z and gear a specific bike for higher pedal assist.
At 30mph, the wind past my ears is loud enough to drown out any motor noise and My1018z gives just a smidge more power ...

Most impressive is that full throttle top speeds are both in the 80% efficiency range!
80% efficiency is likely sustainable at most any cruising speed, on level ground.
This is important considering the limited heat dissipation of this reasonably air tight motor.
Not designed for stop and go traffic or climbing hills, but looks satisfactory for cruising, even at impressive speeds.

Are there any motors that use the same interface, and can be a drop-in replacement for the XYD-16?

However there are advantages to the MY1018z!
1. straight cut gears are more durable
2. straight cut gears allow 100% durability in CW and CCW directions. Works just fine in forward and reverse directions, mobility scooter, small 3-4 wheel applications etc.
3. direct and extended testing demonstrates a slight speed and power advantage ~5%+

Click to expand...

Interesting so going from strait cut gears to helical in a single stage caused a 5% loss of speed ? so imagine how much the losses would be if it was multi stage helical like the bafang mid drives ? I would image 7 to 10% for 2 stage helical vs strait cut kits like the cyclone types with strait planetary spurs.

Have you tried also putting noise reduction covers over the gearbox ? it would help reduce the noise and then you would have high efficiency and also reasonably low noise with no downsides. As you point out about a certain speed the wind noise is more then the gearbox.

Any cover would likely reduce the natural convection cooling, so I would recommend against.
Alternately, a simple shield between motor and riders ears might make trips more enjoyable, as long as it doesn't restrict air flow.

Tho ... at 20mph+ I appreciate the warning supplied to unwary pedestrians!

spinningmagnets said:

Are there any motors that use the same interface, and can be a drop-in replacement for the XYD-16?

Click to expand...

There are 3 similar gear reduction motors:
The MY1016z
Which appears to have an identical bolt mounting pattern

Specifications:

MY1016Z
24 Volt DC Operation
Permanent Magnet DC Motor
No Load RPM: 3850
No Load Current: <2.2 Amps
Rated Wattage: 350W (0.33 Horsepower)
Rated Load RPM: 3000
Torque (NM): 1.1
Rated Current: 18.7 Amps
Efficiency: 78%
Reduction Ratio: 9.78:1
Direct Drive (No Free Spooling)
Suitable for Forward and Reverse Operations
Base Mount Model
9 Tooth Sprocket for 1/2" x 1/8" Pitch Chain

This motor is capable of rotation in either clockwise or counter clockwise by reversing the motor's power wires.
Please note that these would be illegal to connect to your Electric Bike or Scooter, The maximum legal limit is 200w.

The MY1018z
The predecessor to the XYD-16

Specifications:

24 Volt, 25A Rated Load, 2.5A No Load
9 tooth sprocket for 1/2'' x 1/8'' pitch bike chain
1.43Nm at the output sprocket @440 RPM
12 gauge power leads
Gear Ratio: 79:11 (7.18:1)
Weight: 2.2KG (alloy motor and frame!)
Reversible, motor can run in either direction simply by swapping the motor leads to the opposite polarity!
Alloy case for good heat dispersion.
Bicycle style mounting bracket available as an optional extra (Suits the 250w and 450w models)
9 Tooth Sprocket for 1/2" x 1/8" Pitch Chain

Warning !

Please note that these would be illegal to connect to your electric Bike or Scooter as in most states the legal limit is 200W (or in some states 250W with a peddled sensor)
While the maximum legal limit is 200w, you could voltage or current limit this to bring it down to the legal power requirements.
And remember, If you overdrive this motor, under heavy loads it CAN pull over 130 AMPS on a 24V supply!

The MY1020z
Much wider! Designed for applications not requiring limited size. Appears to have active cooling!(?)


Comes in multiple voltages and watt outputs


Not bolt on compatible. But a marked enhancement is the
MY1020ZX Dayton 800w (1HP), 36V DC Planetary Gear Motor, 500 RPM
Gear reduction method should be nearly silent.
Not feasible for eaBike application but ideal for eTrike or small project vehicle?



Specifications:

Permanent Magnet DC Motor
Voltage: 36 Volt
No Load RPM: 3400
No Load Current: <2.4 Amps
Rated Wattage: 800W (1.01 Horsepower)
Rated Load RPM: 3200
500 RPM at gearbox output (+/- 5%)
Torque (Nm): 12.5
Rated Current: 26.7 Amps
Efficiency: 78%
Reduction Ratio: 6.67:1
Direct Drive (No Free Spooling)
Suitable for Forward and Reverse Operation
Base Mount Model
12 Gauge Power wire
10 Tooth Sprocket Suits chain types #40 or #420

Mounting bracket measures 5-1/2'' W x 4-1/2'' L with 4 mounting holes.

Please note that these would be illegal to connect to your electric Bike or Scooter.
The maximum legal limit is 200w, though you could voltage or current limit them to bring them down to legal power requirements.

Nov 14, 2014 10:58 pm

Any cover would likely reduce the natural convection cooling, so I would recommend against

Click to expand...

The gears inside are metal right ? so they don't need any cooling. Where you don't want to block the cooling is on the motor but the gearbox often in industrial applications they cover it with a noise cover. If you need cooling on the gears oil in the gearbox will cool them better then anything else as grease provides no cooling effect. So you could easily make a cover just over the gearbox portion that would stop a lot of noise compared to the thin alloy covers it has.

The XYD-16, and similar, are designed for maximum performance, for their size, but then limited by reduced current.
This seems to make them ideal ... for specific applications!
Other applications, ... not so good.
For identification purposes:
"Mid Peak" or "MP" = the full current model, which has maximum power, (watt), output at ~40-50% of top unloaded motor speed
"Top Peak" or "TP" = the restricted current model, which has maximum power, (watt), output at ~80-90% of top unloaded motor speed



Mid Peak (MP) motor advantages:
For the standard user, with a mix of terrains and gradients the MP motor would seem to be much preferable!
Acceleration is excellent for attaining cruising speed
Is very efficient at cruising speed
If it starts to climb hills at top speed, motor applies more power (watts) as it slows down, giving more power where needed (till below ~50% of top speed)

Mid Peak (MP) motor disadvantages:
Possibly the only disadvantage - the increased inefficiency and heat production at lower speeds

TP Peak (TP) motor advantages:
Ideal for specific applications!
For those who use the eBike as an eaBike (electric assist Bike)
Gearing allows excellent pedal assist at lower speed, reducing as speed increases, this blends nicely with the increasing power (watts) applied by the TP regulated motor

Rather than a central peak of power, power is more even and progressive.

Where this type, and specifically this motor, might shine is as a mid-drive motor
Very similar to a gas motor the HP peaks near top rpm
This allows the very familiar winding motor to top speed then shifting into the next gear for maximum acceleration

TP Peak (TP) motor disadvantages:
From top speed, when you hit a hill, motor assist decreases along with your speed, creating a speed-torque downward spiral
(However, dependent on gearing, torque should increase greatly during initial speed loss)

I modded a graph to compare Mid vs Top peak motor outputs



Not specifically accurate, more a reasonable representation that allows watt output profiles.
The efficiency graphs also demonstrate a marked bonus for the TP motor.

Oh!
While the MP motor has maximum output at ~50% efficiency ...
The TP motor has maximum output at near 80% efficiency!

However, please note that output and efficiency profiles can be greatly improved-moderated by applying restraint to throttle positioning!