front hub kit on a Sun EZ3

[ddk]

Today (6-12) I started on a project to change my neighbor's Sun EZ3 into a SUPER DUPER high PERFORMANCE E-vehicle
capable of attaining speeds up to and possibly including ... 10mph.

The Sun EZ3 screams for a mid-drive system, but I recon it would be best for the neighbor's project to go the far simpler route of installing a front-hub geared motor, not unlike my previous EMoto trike and the main drive system on my My Trike (which also uses a mid-drive system, good for confusing this board's limited thread directories)
-Less maintenance problems with a hub motor; as chain-drive systems inherently require occasional readjustments. And less maintenance is an IMPORTANT FEATURE for this project.

Wholly barnacles, that 16" wheel looks mighty tiny sitting next to the My Trike front wheel...

This 16" wheel further limits my options to either using a magic pie (not a good choice due to local topography) or having a custom wheel built with a geared hub motor. (better choice for all the local hill-climbing on the coast)
However, a third option suddenly appeared.
When I queried about a possible build with Terry@highertekbikes he mentioned he'd recently ordered some 750w Aotema motors mounted in... 16" wheels.
Yesterday he emailed me a message simply stating "The Motors Have Arrived".
(oh, and the price LOL)

There is a fourth option for the Sun EZ3 that involves changing the front fork to accommodate a larger front wheel and, in fact, one supplier of e-bike motor kits does just that. (whom I've unfortunately forgotten) They provide a "free" front fork with a wheel kit specifically for Sun EZ3 and it's varients.
The problem with this fourth option is the Sun EZ3 itself.
Compared to the My Trike, the EZ3 with it's normal 16" front wheel requires a much higher leg lift to successfully clear one's foot over the frame. (yes. I was unsuccessful in my first attempt, doing a passable Gerald Ford impression)
A taller front wheel would exacerbate this condition, which is a concern for anyone with limited physical dexterity. (like me, for instance)

The main difference between My Trike and the Sun is the EZ3 uses a 16" front wheel and the former uses the 24" version.
And My Trike with it's 24" wheel WOT = 20MPH @40V.
I haven't calculated the TOP SPEED of the Aotema motor mounted in a 16" wheel fed from a 40V battery because the highertek website doesn't list the RPM of the motor directly, but mentions the motor should give 22mph in a 26" wheel.
Assuming Terry meant 22mph using the standard controller and a 36V battery, a simple ratio calculation indicates the Sun EZ3 with it's soon-to-be Aotema-equipped 16"wheel might have a top speed of a hill-munching 13mph.


...so this is the beginning of This Thread.
I ordered the Aotema 750wmotor kit and a battery today. (well, yesterday mid afternoon-ish)

My neighbor, whom we'll call "Bob" because it's easier to type than "neighbor" (and less chance of mistyping, as I've managed three times now)
Bob doesn't need nor want to travel far. Where we live, 10 miles pretty much covers the whole civilized area.
Bob has had some experience with electric vehicles before this moment in time. Bob successfully killing several poor, (sic) defenseless SLA battery packs by forgetting to recharge them for weeks (and months) at a time
Therefor Bob needs a simple-to-use battery with possibly less shelf self-discharge.
LiPo would likely be Bob's nemesis.
-So I ordered a 36V 10AH LiFePo4 for him, thinking the cost of a replacement battery might be just enough money to jar Bob's memory on the recharging issue.

...only time will tell

 

[dogman dan]

For the purpose of calulating the motor speed only, you could go to the Grin Cyclery simulator, and use the 2806 9 continent motor setting. Similar speed motors, close enough.

It's a slightly fast winding, which normaly would be a plus with a tiny rim.

There is an option for crazy slow, Methtek still has a 2812 9c motor in 20" rim. You'd have to relace of course.


One thing though, that aotema kit comes with a 22 amp controller. So you'd be pushing a 2c cells 10 ah pack in my opinion. But not by much, if the guy never selects full throttle, ever. So like my wife, who'll never draw more than 5 amps on any ebike, he should be ok with your battery selection.

But like my wife, he might prefer a more underpowered motor, which gives better fine throttle controll at really low speeds. Cut a shunt wire and make it a 10 amp controller?

 

[ecowheelz]

We did this EZ3 a couple years ago:



At the time, we used a Crystalyte Roadrunner (which are no longer available). If we were doing one today, we'd get a 16" wheel built by Jason at E-BikeKit...

 

[dogman dan]

Yep, he's got that 2810 winding motor in the trike kit. Since he does his own wheel lacing, he'd likely be ok with making one in 16" rim. normal is 20" but other sizes are $30 more. So likely $30 would get you a 16" rim version.

 

[Airjnke]

After a few years on an EZ3 I've finally arrived at this configuration. Changed the 16" X 20" layout to a 20" X 24". Because of the 8" head tube length I had to weld an extension on a 20" front fork tube. Put a Maxis Hook Worm 1.95 running at 70 psi in the front. The back has some 3" Kenda flames running at 40 psi. Installed a springer seat I found on the web but I don't think they are made anymore. Between the springer seat, larger dia wheels & low psi rear tires it really smothes out the ride. Both have a 36v C'lite 405 motor with a 14ah SLA on one trike & a 36v 20ah Lifepo4 on the other. The Watts Up? meter has served me well especially for the price. Last was a Windwrap fairing made for the EZ3. Liked this config so well I made two of them.
Airjunkie

 

[Rassy]

DDK, I think Bob will be okay with the 10AH battery. I've used a 48V 10AH Ping on my trike for the last two years. The controller is limited to 23 amps and I often pull over 20 amps when pushing hard up hills.

The bigger problem with the EZ3 SX is the offset low slung deraileur. By offset, I mean it is ahead of the rear wheel axle, and thus it will catch on a very low obstacle. Airjnke's bigger wheels and tires would help eliminate that problem. For my brother, (pedal only, post stroke) I shortened the chain, which eliminated use of the larger front chainrings, but keeps the deraileur higher when in low gears. Eliminating the faster gears has worked fine since we didn't want him to be a speed demon at this point.

As far as getting on and off the trike my brother has not had any problem even with limited use of one leg. Having over seat steering so there are handlebars to hang onto helps compared to tadpoles or the Sun EZ3 USX.

 

[ddk]

We did this EZ3 a couple years ago:



At the time, we used a Crystalyte Roadrunner (which are no longer available). If we were doing one today, we'd get a 16" wheel built by Jason at E-BikeKit...

clean build!
under-the-seat controller installation noted-
I'm thinking of using the seat support brackets to support the battery sled, as the cg will remain forward the rear axle.

 

[ddk]

Yep, he's got that 2810 winding motor in the trike kit. Since he does his own wheel lacing, he'd likely be ok with making one in 16" rim. normal is 20" but other sizes are $30 more. So likely $30 would get you a 16" rim version.

Thanks for the suggestion
-maybe the next time I do an EZ3..... :lol:

The guy who bought the local sign-shop owners' EZ3 is likely monitoring This Thread. (per discussions) so he can make do with suggestions that, because I'm a self-centered a**hole who thinks His Opinion is The Best Opinion, I rarely take suggestions for.

 

[ddk]

After a few years on an EZ3 I've finally arrived at this config. Changed the 16" X 20" layout to a 20" X 24". Because of the 8" head tube length I had to weld an extension on a 20" front fork. Put a Maxis Hook Worm 1.95 running at 70 psi in the front. The back has some Kenda 3" running at 40 psi. Installed a springer seat I found on the web but I don't think they are made anymore. Between the springer seat, larger dia wheels & low psi rear tires it really smothes out the ride. Theres is a 36v C'lite 405 motor on it with 14ah SLAs. The Watts Up? meter has served me well especially for the price. Last was a Windwrap fairing made for the EZ3. I liked it so well I built two of them.
Airjunkie

?did the extension maintain the top-tube height?

I choose not to diddle with a bigger front wheel as Bob can't physically lift his leg over the EZ3 top bar without assistance.
...Bob manages the EMoto well enough, whose crossbar is several inches lower than the EZ3.

Bob's not a hardcore trike rider like I am.
The Bobs are into pleasure riding only... mainly to entertain their cats, I'm thinking.

 

[ddk]

DDK, I think Bob will be okay with the 10AH battery. I've used a 48V 10AH Ping on my trike for the last two years. The controller is limited to 23 amps and I often pull over 20 amps when pushing hard up hills.

The bigger problem with the EZ3 SX is the offset low slung deraileur. By offset, I mean it is ahead of the rear wheel axle, and thus it will catch on a very low obstacle. Airjnke's bigger wheels and tires would help eliminate that problem. For my brother, (pedal only, post stroke) I shortened the chain, which eliminated use of the larger front chainrings, but keeps the deraileur higher when in low gears. Eliminating the faster gears has worked fine since we didn't want him to be a speed demon at this point.

As far as getting on and off the trike my brother has not had any problem even with limited use of one leg. Having over seat steering so there are handlebars to hang onto helps compared to tadpoles or the Sun EZ3 USX.

excellent info per usual Rassy.
Ya gotta stop doing that!

For the meanwhile, until Bob undergoes some chassis rebuild, I'm reversing one of the cranks by 180 degrees as a simple, reversible footrest solution.
Should Bob's rebuild go smoothly than I'll suggest/make whatever mods Bob prefers to the chain.

However, Bob has ridden this trike for several years without indicating ever having issues with derailleur catchment.
(it's likely Bob has never used the largest chainring :lol: )

 

[ddk]

...about that derailleur issue.
What the heck is it about Sun bikes and these derailleurs?
That was one of those endearing 'features' of the Sun USB SX that nailed my decision not to buy it.




As with my thread about My Trike (http://endless-sphere.com/forums/viewtopic.php?f=3&t=36490) I'll basically interject off-topic crap as I see fit.
Today's off-topic discussion (by one, me) involves the Bell version of Slime tubes

Verdict:
"It Sucks"
-In fact, the Bell self-sealing tubes hold up to road debris as least, or almost as well as any random untreated tube.
...I guess you sumtimes getz what you payz, the Bell self-sealing tubes being several dollarinos cheaper than the Slimes.

I've modified my workshop with SHADE

 

[docnjoj]

About 2 years ago I set up a USX (similar to the EZ-3 but with underseat steering and we have not had any problem. even with the "speed bumps" they are so fond of using on our residential streets. It looks low (the deraileur) but seems to work OK. We have the front wheel as a 20" 9C since it came with the 20 originally. Sun may be willing to sell the fork and tube at a reasonable price to allow a 20 wheel on the Ez-3. Their parts are not really expensive.
otherDoc

 

[Rassy]

Sort of a repeat of my last post, but the difference between the Sun USX and the other Sun delta trikes is that the deraileur is under the axle for the USX and thus it moves up and over obstacles with the rear wheels. With the other Sun delta trikes the deraileur and gear cluster are on a jack shaft ahead of the rear wheel axle and thus catch on things before the rear wheel gets to them.

I always figured it would be easy for Sun to design a deraileur that was at least an inch shorter to help avoid this problem. A "taller" tire would also help.

 

[ddk]

About 2 years ago I set up a USX (similar to the EZ-3 but with underseat steering and we have not had any problem. even with the "speed bumps" they are so fond of using on our residential streets. It looks low (the deraileur) but seems to work OK. We have the front wheel as a 20" 9C since it came with the 20 originally. Sun may be willing to sell the fork and tube at a reasonable price to allow a 20 wheel on the Ez-3. Their parts are not really expensive.
otherDoc

as Rassy (repeatedly :lol: ) pointed out, the difference between the EZ3 and the USX is the location of the derailleur arm

Sort of a repeat of my last post, but the difference between the Sun USX and the other Sun delta trikes is that the deraileur is under the axle for the USX and thus it moves up and over obstacles with the rear wheels. With the other Sun delta trikes the deraileur and gear cluster are on a jack shaft ahead of the rear wheel axle and thus catch on things before the rear wheel gets to them.

I always figured it would be easy for Sun to design a deraileur that was at least an inch shorter to help avoid this problem. A "taller" tire would also help.

As I see it, if I owned this trike my simplest solution for the EZ3 is simply raising the jackshaft a few inches.
Not a problem raising the jackshaft, since the EZ3 comes equipped with a power idler already installed.
Of course I would also add another gear to the 15mm axle, driven from a geared-hub motor along with a front hub motor.
But that's because I prefer having two motors working half as hard as one motor when climbing mountains.



As I noted about the trike's owner, Bob's never mentioned previously having any problems using the trike as is but Bob's currently physically unable to pedal it (for the time being) -and our little oasis is cursed with tall speed bumps.
Therefor the simplest solution is for me to shift the gears where the derailleur arm no longer poses a concern before returning the trike to it's owner (for the time being) :lol:
This is Bob's trike, and should Bob regain physical prowess I would only suggest to Bob that replacing the gear cluster with a multi-speed hub would be the most reliable solution (though not the cheapest).

On a completely unrelated subject, I managed to pedal 196 miles this week.

 

[Rassy]

ddk wrote:

On a completely unrelated subject, I managed to pedal 196 miles this week.

My buddy Bob (that you met on my last trip down your way) was here over the week-end and we pedaled about 60 miles. But in my case I use the word loosely since I used almost a KW of battery juice. 69 year old Bob on the other hand has no assist on his trike and he did pedal the distance.

We also hiked to the top of Humbug Mountain which is 2 1/2 miles, uphill all the way, and 3 miles down the other side. Even found a couple of ripe Salmon berries next to a little waterfall.

 

[ddk]

ddk wrote:

On a completely unrelated subject, I managed to pedal 196 miles this week.

My buddy Bob (that you met on my last trip down your way) was here over the week-end and we pedaled about 60 miles. But in my case I use the word loosely since I used almost a KW of battery juice. 69 year old Bob on the other hand has no assist on his trike and he did pedal the distance.

yep, you and Bob put me to shame, although in my defense I have to limit a particular muscle from over-exertion, otherwise it quickly goes into 'thermal runaway'

We also hiked to the top of Humbug Mountain which is 2 1/2 miles, uphill all the way, and 3 miles down the other side. Even found a couple of ripe Salmon berries next to a little waterfall.

Before 2009 I hiked the Humbug a couple of times. It 'was' one of my favorite hikes!
My other favorite hike 'was' arch rock, down to the beach and back.
Nowadays if I can't bike it I can't go.
Biking a path provided the testing material for Bell self-sealing tubes, and they failed the encounter with blackberries. :lol:

 

[docnjoj]

Sort of a repeat of my last post, but the difference between the Sun USX and the other Sun delta trikes is that the deraileur is under the axle for the USX and thus it moves up and over obstacles with the rear wheels. With the other Sun delta trikes the deraileur and gear cluster are on a jack shaft ahead of the rear wheel axle and thus catch on things before the rear wheel gets to them.

I always figured it would be easy for Sun to design a deraileur that was at least an inch shorter to help avoid this problem. A "taller" tire would also help.

That is a really good point Rassy! The USX series has separate axles and negative camber to help with stability. Unfirtunately it makes and mid-drive gear box only supported on one side and thus possibly way open to failure. It does make the trike more stable, however. My wife is yet to tip the USX, but she does keep trying! She made it to two wheels a couple of times.
otherDoc

 

[ddk]

Sort of a repeat of my last post, but the difference between the Sun USX and the other Sun delta trikes is that the deraileur is under the axle for the USX and thus it moves up and over obstacles with the rear wheels. With the other Sun delta trikes the deraileur and gear cluster are on a jack shaft ahead of the rear wheel axle and thus catch on things before the rear wheel gets to them.

I always figured it would be easy for Sun to design a deraileur that was at least an inch shorter to help avoid this problem. A "taller" tire would also help.

That is a really good point Rassy! The USX series has separate axles and negative camber to help with stability. Unfirtunately it makes and mid-drive gear box only supported on one side and thus possibly way open to failure. It does make the trike more stable, however. My wife is yet to tip the USX, but she does keep trying! She made it to two wheels a couple of times.
otherDoc

If I remember correctly (unlikely) the usx could be modified fairly cheaply for a mid-motor.
Rebuilding one of the stub axles is all that's required.
The actual deciding factor for me to not purchase the usx was the cost of replacing the cranks and their position as delivered from the factory :| I was unable to find anything less than $200 for new crank arms and realized I needed the cranks to be substantially lower on the trike. These are the reasons I built my own 'crank forward' (a rans term for semi-recumbent) trike to suit my particular pains.
It cost considerably more than the usx to do so, even when using poorer components.
Cost is indifferent to pain, which I have none of when riding my trike.

I've only purposely tipped my trike once, to avoid being smashed by a truck, otherwise I corner without tipping up to the full speed of the trike (20mph)-although that was really scary the first time i did it. :lol:

 

[ddk]

-received all the electrical stuff
and it started raining :lol:
my shade-shelter fails the water test and I didn't expect it to be waterproof. I also didn't expect rain this time of the year :?

out of nowhere, Bob mentions the derailleur; I mention my thoughts about the least expensive 'fix' (multi-speed hub)
-Otherwise I think Bob will have a bigger (taller) problem mounting the trike (already does) using 24" rear wheels, which would also cost about the same as the multi-speed hub 'fix'.

There's still the issue of the crank arms being too long, in my opinion.
170mm cranks put too much movement on hips/knees and the semi-recumbent, or crank-forward position already accentuates knee pain.

 

[docnjoj]

-received all the electrical stuff
and it started raining :lol:
my shade-shelter fails the water test and I didn't expect it to be waterproof. I also didn't expect rain this time of the year :?

out of nowhere, Bob mentions the derailleur; I mention my thoughts about the least expensive 'fix' (multi-speed hub)
-Otherwise I think Bob will have a bigger (taller) problem mounting the trike (already does) using 24" rear wheels, which would also cost about the same as the multi-speed hub 'fix'.

There's still the issue of the crank arms being too long, in my opinion.
170mm cranks put too much movement on hips/knees and the semi-recumbent, or crank-forward position already accentuates knee pain.

My wife's USX has 165 mm pedals but she doesn't seem to have knee problems. I had to go to 150 mm cranks on my trike because of bad knees and it really helped. Shorter stroke really reduces the knee angles that need to be used. That said you really have to use the gears with short cranks.
otherDoc

 

[ddk]

-received all the electrical stuff
and it started raining :lol:
my shade-shelter fails the water test and I didn't expect it to be waterproof. I also didn't expect rain this time of the year :?

out of nowhere, Bob mentions the derailleur; I mention my thoughts about the least expensive 'fix' (multi-speed hub)
-Otherwise I think Bob will have a bigger (taller) problem mounting the trike (already does) using 24" rear wheels, which would also cost about the same as the multi-speed hub 'fix'.

There's still the issue of the crank arms being too long, in my opinion.
170mm cranks put too much movement on hips/knees and the semi-recumbent, or crank-forward position already accentuates knee pain.

My wife's USX has 165 mm pedals but she doesn't seem to have knee problems. I had to go to 150 mm cranks on my trike because of bad knees and it really helped. Shorter stroke really reduces the knee angles that need to be used. That said you really have to use the gears with short cranks.
otherDoc

I've never experienced knee pain before the My Trike project.
Pedal-forward is just that much difference on the my knee ligaments/muscles.

I use 142mm cranks on the My Trike :lol: no pain. I have several choices of cranks on hand from the 142mm to the 170mm sizes and since I'm using a single-piece crank, I have all of 20 bucks invested in my 4 sizes.
And I do use all my gearing, all the time. And unlike the EZ3 I only getz to choose 1 of 5

 

[ddk]

the ez3 is now an e-trike.
too late, too dark... no pics

extensive review to follow but here's some first impressions :

issues... only documentation was the care and feeding of the LiFePo4 battery.
I wonder what the blinking green led on the controller means?

1. I successfully mounted the motor wheel backwards, because the wiring exits backwards of my other two projects.
2. Definitely need torque arms or a new fork because the dropouts are hardly deep enough on the trike's existing fork and there isn't room to file out the fork's dropouts without significantly weakening the part.
3. The sensorless motor jitters a bit from a standstill but quickly smooths itself. (expected and delivered)
4. Far more powerful than my other geared hub motors. The Aotema is a DD rated at 750W.
5. The DD is heavy and cogs, but because it's in such a small wheel (16") I have -0- issues using the pedals only.

The hardest part of the project was making a 6' battery extension out of 8 gauge wire.
Momma don't allow no voltage sags here.

 

[Airjnke]

2. Definitely need torque arms or a new fork because the dropouts are hardly deep enough on the trike's existing fork and there isn't room to file out the fork's dropouts without significantly weakening the part.

Guess I should have mentioned it but now that I think about it that's another reason I went to a 20" X 24" lay out. My 16" fork needed to be spread out to clear the motor casing & then back again to keep the dropouts paralell. Had to file the slot a bit too. The motor with a 20" fork went right on but I had to weld an extension on the neck to make it tall enough. Can't change just one thing without it messing up two others. :?
Airjunkie
http://www.flickr.com/photos/airjnke/3239815217/in/photostream

 

[ddk]

... My 16" fork needed to be spread out to clear the motor casing & then back again to keep the dropouts paralell. Had to file the slot a bit too. The motor with a 20" fork went right on but I had to weld an extension on the neck to make it tall enough. Can't change just one thing without it messing up two others. :?

I call that "one step forward, two steps back"
kind of a dance one plays when building things one hasn't before.

I had no problems with this EZ3 dropouts being wide enough; they are 109mm.

-While doing slow tests the motor walked right out of the dropouts!
... so it's time to order those torque arms

all forks are a bit different, as this motor won't clear the 20" fork that originally came with the My Trike. The dropouts are the same on that fork as what is used on the EZ3 so it likely would have been a problem child had I used it.

for your amusement (if you're stupidly bored, like I get some times) you might check out who makes/supplies the parts that go into the making of a a fork, (or any other part of a bike) as the dropouts, head tubes etc are mass-produced separately from the tube arms.

 

[Airjnke]

-While doing slow tests the motor walked right out of the dropouts!
... so it's time to order those torque arms
Yikes! Here's the dropout width off the original fork with a refurb BD36 installed. The axle width was good but I spent much time on groups trying to find out which was best(or worst)to grind so I lightly touched up both the axle radius & the bottom of the dropouts. Still not sure which is best but I rode it like that for a couple of years no problem. Had to make some washers to fit in there nicely and a torque arm. The 16mph max speed I could get on it might have saved my butt.