GL1 Hub Motor Kit:
Movie of GL-1 motor in 26" rim at 40km/hr here
The GL1 Kit is a motor which has almost identical speed and torque
characteristics to the Crystalyte 408 motor. GL1 weighs 5.8kg and is 18cm in
diameter.
This motor is used on ebikes in china (which are more like mopeds or small
motorbikes) so its made for the Chinese market in large numbers and hence
cheaper prices (the motors are hand wound as I discovered on a recent
visit to a factory that produces them)
There are some similarities and differences to the 408 which I will outline :
1. top speed at 48volts on 26" rim = 40km/hr ( 408 top speed is
40km/hr at 48volts also)
2. torque is quite similar to the 408 but the GL1 controller limits the maximum
amps to 18amps where as the 408 controller can go up to 20amps (so simply due to
controller there is more torque with the 408).Also there are differences in the
thickness of the copper wire and number of windings in this motor compared with
the 408.
( I did a test ride against the 408 with Tony Mathews of Surfers Paradise he was riding the 408 motor
, I was riding the GL1, we were quite evenly matched, though as the GL1
has a maxiumum current draw of 15amps (now the controller has been
increased to 18amps) on the ride home I was still zipping along
at 40km/hr whilst he had used 20amps of current at times which drained his
batteries quicker I assume, and he was stuggling along for the last 5 or 6 km, we did
about a 30km ride that day from Surfers Paradise to Burleigh Heads and back)
3.There are also some differences in the thickness and number of turns of the
copper wire windings for each motor. I'll outline later when I find out the
exact structure of the GL1 windings.
3. GL1 only available for rear wheel.
4. the main difference between the motors is that the 408 has its axle longer
at one side to make it easy to fit a 6 speed cluster on (the downside is the
brake pads will need re-alignment as the wheel is moved to one side slightly).
It is quite ok to use a 6 speed cluster on the GL1 though it does make the total
dropout width needed wider than a standard bike by about 1cm.
5. One advantage of the GL1 over the 408 is that it has a thread on one side
of the motor for a bandbrake or disc brake. I find with the extra weight of
motor and batteries that good brakes are a must. Band brakes are quite cheap to
fit on the motor and give a very good rear brake.
If you use aluminium rims with pad brakes you wont need a band brake or disc
brake on the motor, aluminium rims provide very good braking compared to steel
ones when using caliper or 'v' type pad brakes.
I have ordered some disc brakes to suit fiting on a hub motor but
haven't as tried them. The Crystalyte kits do not have a thread for a brake
(on opposite side to cluster) as they have no room since the axle has been
shifted to make way for a 7 speed cluster.
6. One other advantage is that the controller that comes with the GL1 kit has
regenerative braking. Its quite a sophisticated controller, I recently met the
designer of the controller who tried to explain to me how it works (I think he
succeeded to some degree!). Its a
very interesting way that the regenerative braking is produced via the
controller (see controllers section) and certainly not how I thought it would be
produced.. Usually regenerative braking controllers
can be quite expensive though this particular one is produced by a leading ebike
manfacturer near Shanghai and is in used on many tens of thousands of their ebikes in
China so its a well and truly tried and tested regenerative braking system.
6. Like the 408 the controller on the GL1 can also run on 36v
or 48volt
[postscript: I am now finding it difficult to get the 36v/48v controller so I
will have to supply with 48volt controller only for the moment]
Crystalyte
motor kits have NO regenerative braking function built into their controllers.
7. because its a gearless motor there is no freewheel mechanism in the motor,
but once installed in a rim with a tyre the resistance to turning is negligible
and the bike can be riden like an ordinary bike. The resistance against turning
is called cogging, but it is very small amount of resistance.
If you try turning the shaft in the motor by hand it will appear difficult to
turn, but once installed in a bike the resistance is very small indeed.
GL-1 installed in Neddies bike (in Sydney Australia):
The Picture below shows GL1 being used as a front motor (its really a rear motor) on an experimental trike
(hence the strange twin forks at the front). I will replace with a picture with
motor being used on rear as time permits. Its a good example of how you can use
a rear hub motor on the front, but this did require me to pull out the front
forks by a cm or two! [postscript: it recently came to my attention that
the motor can be installed in the front by removing both the threads off each
side of the motor and lengthening the flat on the axle shaft, you can get the
motor width down to about 10cm!).
Front forks were steel (not aluminium!!!!) and reinforced with a second set of
fork tubing from another bike, the old stick welder comes in handy some times!
Torque Graph of GL1 shown below:
I've overlaid some of the more important figures on the graph below :
Below is the original graph:
Some notes from graph:
Unloaded:
360rpm @ 0.749amps
Maximum Torque:
41.77 Nm @ 17.796amps
Maximum Efficiency:
87.44% @ 331rpm @ 6.45Nm @5.333amps @ power output of 223.6watts (hey thats
not bad....87% its creeping up!!!!)
Maximum Output Power
654.1watts @76.15%efficiency@252rpm@24.79Nm@17.911amps
For an explanation of the graph see torque graphs section
Dimensions of GL-1
Picture below shows how to calculate the offset, the offset means the centreline
of the motor is shifted to one side depending on the width of the cluster used.
It means that brake pads will need to be adjusted to suit as the rim of the
wheel will be shifted to one side in the bike frame due to puting a cluster on
the motor. For example a three speed cluster has a width of 19mm, once installed
on the motor it will mean the rim will be sitting 4mm (19mm-15mm = 4mm)
off the central axis, so the brake pads will need to be adjusted to suit the
sideways movement of the rim.
Below comparison of crystalyte 408 and GL-1 hub motors to show how cluster
effects offset of rim to one side. The crystalyte motors have more offset with a
7 speed cluster as the thread for a brake on one side is removed, brake pads
need to be adjusted to account for this offset. GL-1 has less offset but still
requires brake pads being adjusted to suit. (note the 408 at the top has a 7
speed cluster and the GL-1 has a 6 speed cluster installed).
It is possible to get the tyre in the centre of the bike with no offset by
puting some dishing in the spokes, this means having the side of the rim where
the gear cluster is the spokes are almost vertical and on the other side they
are at an angle. There is a bit of an art to dishing the spokes of a rim, I'm
not very good at it, so wont put any instructions up until I get better at doing
it!!
INSTALLATION INSTRUCTIONS FOR GL-1
If your ok using the 3 speed cluster supplied with the motor steps below are not
necessary (go to step 4)
Before spoking the motor into a rim, it will be necessary to adjust the width
of the thread on the motor to suit whichever cluster you will be using.
A three speed cluster will come installed on the motor. If you wish to use more
than 3 speeds in order to fit the motor into the standard rear width of the
frame (14.5cm) it will be necessary to remove about 5mm of the thread on the
side of the motor that has no wires coming out of it.
I find that when you have a hub motor it is not necessary to have as many gears
hence I've supplied 3 speed clusters with these motors (in fact all the island
earth motor kits come with a 3 speed cluster installed ).
If you intend to install a 5,6 or 7 speed cluster it will be necessary to cut
5mm off the thread on the motor to keep the width of motor to a minimum so that
it will not be necessary to spread the rear frame to accommodate the motor. The
picture below shows that the motor has 15mm of thread but a standard
cluster only has 11mm so its necessary to take off about 5mm of the motor
thread.
Picture above shows the 5mm gap that can be removed by following the steps
below.
Step 1: mark and cut off 5mm of thread
Note: the thead on the side of the motor with no wires!!! this is where the
cluster goes.
The thread is aluminium so it is quite easy to cut with a hacksaw. But it should
be done accurately or it may be difficult to get the cluster onto the thread
later if it is done poorly.
Once you go right around the thread the cut should line up with where you
started the cut.
Step 2: Clean up the cut and thread
Clean up the cut with a file. Note in the second picture below go around the
edge of the thread very gently to remove the rough edge. Lastly clean up the
thread with a wire brush (just to clean out any debris).
Step 3: Install the cluster
Sit the cluster right up against the thread, move the cluster backwards
(anti-clockwise) until you feel it sit on the thread correctly, then rotate
cluster clockwise onto the thread, if all goes well the cluster should go onto
the thread no problems. Don't force the cluster onto the thread, it should go on
easily, if it doesn't just clean up the thread again with wire brush.
Picture below shows a 6 speed cluster installed on the motor after cutting
off 5mm of thread.
Step 4: Spoking
Spoke the motor into your rim: see http://www.users.bigpond.com/solarbbq/spoking.htm
Next use Step 5a if using a 3 speed cluster or use step 5b if using a 5,6 or
7 speed cluster.
Step 5a: GL-1 installation using 3 speed cluster supplied with the
motor kit
(to be inserted sooooooon)
Step 5b:GL-1 installation using 5,6 or 7 speed gear clusters
(note: with the three speed cluster that comes with the motor it will fit into
the rear of a standard bike without the need to remove the brake thread off the
motor so the step below wont be necessary!)
Before you do this part read the whole section first to get an idea of what is
involved. Also make sure the cluster you use (if not using the 3 speed cluster
is as close to the motor as possible when screwed on the gear thread side of the
motor, it may involve taking off about 7mm of the gear side thread of the
motor).
If using another cluster apart from the 3 speed cluster supplies with the
motor it may be necessary to make some fairly major adjustments to the motor to
allow room for the larger cluster. The motor is designed for use in chinese
ebikes which will normally only use a one speed cluster. Hence the need for some
DIY work.
The first option is to spread out the width of the rear frame to accomodate
the motor with 5,6 or 7 speed cluster. Usually frames can be spread quite easily
just with hands and feet and some force. If your not keen on that idea, the
below are details on how to do it another way.
Step 1: Cut off the brake thread as shown by white line in left picture below,
make sure you cut off the thread on the side of the motor which has the motor
wires coming out of it (the other side of the motor is for the gear cluster).
The thread is aluminium and quite easy to cut.
It should look a bit like the pictures below, note in these pictures I could
have cut more thread off (theres is about 5mm of where the brake thread was I've
left in place) but at that time I wasn't sure if it would effect the brearing in
the motor, but the bearing is located deeper within the motor so its no problem
to cut a bit further back then shown in these pictures.
Below I've filed off the extra 5mm I could have taken off initially.
Step 2:
Just place in motor in the upside down bike frame and check if you have
enough width. You need about 5mm gap on both sides between motor and frame.
Side view of the above right hand side picture.
Step 3:
Next you need to cut with a hacksaw some slots in the axle. The idea is to
extend the flat part of the axle to within about 5mm of the motor.
Cutting a slot will define where the new flat will end and give place where the
bike frame can sit against.
White dotted line below shows line along where the flat part of axle will be
extended.
Picture below shows the top view ready for the grinder. Right hand picture below
shows after grinding the flat part to where the slots were cut with the hacksaw.
Step 4:
Next it is necessary to adjust the axle so the torque washer can slide
right up to the motor. Theres two ways to do this, you can either file out the
hole in the torque washer so it will slide right along the axle to the motor, or
grind a bit off the rounded edges of the part of the axle near the motor so the
torque washer can slide across.
Repeating the same procedure as before I make a slot with a hacksaw to define
where the grinding will end.
Getting out the trusty grinder and taking a bit off the rounded part of
axle, then filing smooth, note in the picture on the right below you can see a
well defined circle where the flat of the axle ends (the place where the slots
were made with the hacksaw). That circle can be also be more well defined with a
small file if necessary.
Check the torque washer will slip over the axle now right up to the motor (well
up to where the initial slots were made with the hacksaw).
Step 5: Make a spacer bar to suit your cluster width.
Below I've used two pieces of tube.
You will need to leave about 5mm or a bit more gap so that
the bike frame wont rub on the gear cluster.
Picture below shows the gap needed between the end of the gear cluster
and the end of the spacer tube. There should be enough room so the cluster wont
hit the bike frame when it rotates.
Place the motor and rim into the bike. Make sure the motor doesn't touch the
frame, in this case there was only about 5mm gap as shown by the left hand
picture. The right hand picture below shows the gap between the motor and bike
frame as defined by the initial slots cut in axle with a hacksaw.
You will notice that the wheel has been offset (shifted to one side) by making
room for the larger gear cluster. This wont cause any problems for bike riding,
but will require the brake pads being adjusted to suit the shift of the wheel to
one side. The dotted black line in the left picture below shows how the wheel
has been shifted to one side (black dotted line is centre line of the bike).
Step 6:
Ensure the torque washer lips will sit against the bike frame, it may be
necessary to bend the lip over more by puting the washer in a vice, and hitting
the lip with a hammer to bend it over a bit more.
When all this is done you will see that even though there is some offset
(probably about 1cm or so) that the front and back wheels can still run pretty
much in a straight line, there wont be any noticeable difference when you ride
the bike from when the wheel was perfectly centered.
Picture below shows front and rear wheels in straight line even though rear
wheel is offset somewhat its not very noticeable from this view.
Step 7: Install the torque bar
Installing the torque arm. The torque arm is a necessary part in order to
assure the axle will not rotate in the bike frame. If for some reason a torque
washer does not work correctly then the torque arm is an added precaution.
This is only a suggested way to install the torque arm. Because there are many
variations in rear frames its quite difficult to get a torque arm that would fit
any bike frame, so heres my solution to the problem. (requires a welder).
Cut the torque arm ( with hacksaw) into two pieces as shown below.
Install the flat piece onto the axle as shown below .
Place the other part of the torque arm so it sits next to the bike frame where
it will later be held on by hose clamps. It will be necessary to make a
spacer tube so that the two pieces will line up for welding later. Two views
shown below.
Cut the end of the torque bar which is sitting along the bike frame in the pic.
below (on right in pic below) so that it will join neatly to the torque bar that
is sitting on the axle.
Place some tape on the bike frame to protect it from scratches. Using plastic
cable ties or similar to hold the horizontal torque bar in place so that it sits
right next to the torque bar on the axle. Then just do a tack weld to hold them
together.
Remove the torque bar and make a weld to join the two parts together as shown
below (dont weld while on the bike the paint might be damaged).
Picture below shows torque bar back in position after being welded off the bike.
Make sure the weld is a very strong one. Hit the weld with a small metal hammer
numerous times to remove slag and relieve stresses inside the weld (this will
also test to see if the weld is strong!).
The finished weld shown below (a bit rough!), two hose clamps the same as you
find on radiator hoses will be required (dont use aluminum type hose clamps they
are very weak, use steel ones).
Put the torque washer, spacer tube and torque arm on the axle with the nut. Note
the torque washer can also but put on the inside of the frame between the motor
and bike frame, this will move the wheel axis over by a few more mm towards the
centre line of the bike.
The finished torque arm with the bike turned up the right way on its wheels.
Note the torque washer is not really visible in the pictures below as I placed
it on the inner side of the bike frame to move the wheel centre over just a few
mm more (the tyre was almost rubbing on the bike frame on one side).
see customers pics
section for some other ways to use torque arms.
Neddie in Sydney made his own torque arm which screws into the holes made for a
rear carrier rack as shown below:
to be continued..............installing controller/throttle/brake handles
beware of spray ebike company:
more info
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