Considering a build: I have an Electra Townie Step-Over Men’s 7D bike, a Crystalyte 5304 direct drive rear hub motor, and a 72 Volt battery. Would like to mount the battery inside the frame if possible without dismantling the battery. The battery size is 4” x 5 1/2” x 7” each. There are 2 of them that make the 72 volts together. (See Picts.) Any ideas? Thanks,
72 Volt Electra Townie Rocketship
- Thread starter Bone
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Chalo
100 TW
Can the BMSes on those packs tolerate 70-80+ volts across the leads? If not, you're setting yourself up for failure by putting them in series.
I've electrified a number of Townies and similar bikes, but I would never set one up to go faster than high 20s mph.
I've electrified a number of Townies and similar bikes, but I would never set one up to go faster than high 20s mph.
The battery and motor came from Lithium Batteries, DYI ebike conversion kits, Crystalyte Motors and Electric Bikes, Electric Scooters and was already in use on a Giant Sedona. The previous owner said the bike would go around 40-45mph. I figure if the Giant Sedona frame could handle the power which has a shorter wheelbase than an Electra Townie, then the Townie should be able to handle it.
Chalo
100 TW
You can make a Radio Flyer red wagon go 45 mph, but that doesn't make it a good idea.
Townie is a bike designed for slow casual riding, that can be ridden confidently at somewhat higher than its design speeds on good surfaces. But there are limits. The steering geometry won't settle into a groove at traffic speed like a motorcycle or a downhill bike, because that's not what it's for. It's difficult to impracticable to stand up on the pedals, so both the bike and your spine will get hammered out of shape by road hazards that sneak up on you when you ride at abnormal speed.
You do you. But unpleasant consequences are easily predictable if you try to make a fooling-around bike path bike move at motor traffic speed.
Just because it will go 40-45mph doesn't mean I have to drive it that fast. The main reason why I'm considering building it is to be an economical build. I got a good deal on the Giant Sedona DIY eBike. It is old technology but was the some of the best at its time. It has a 72 volt battery that is good and a 5304 Series Crystalyte Direct Drive Rear Hub Motor that is good as well. The controller and the display on the other hand is not and would have to be replaced. The controller (X-CT7240F) is a 72V - 40A Crystalyte 7240F controller with a Cycle Analyst display. Does anyone know of a controller and display I could use now that would work and replace the bad controller and display? Thanks,
Chalo
100 TW
It's a mistake to set up an EV to go much faster than your anticipated speed. To do that, you have to set up the whole system for more power (weight, expense, temperamental parts) than if you built it to go as fast as you want but not more. And then you end up running the thing in a lower efficiency regime because the sweet spot is at too high a speed.
Stinking gas cars thrive when they loaf at well below their capabilities. But EVs work best when they're run at close to their maximum speed as much as possible.
You got a link to your Townie build?
Turns out it is looking like the Cycle Analyst is fine. It is looking like the BMS is shutting things down to protect the system. The Cycle Analyst comes on for a couple of seconds then shuts off. Looking like it is a bad controller. Sound about right?
Chalo
100 TW
No, but I've done several for friends (including my wife) and several for customers. My honey's is actually a KHS Smoothie, but they're all the same fundamentally. I'll try to get photos when the sun shines. But my usual formula is a front Jump bike front hub motor, maybe or maybe not with its original rim, plus a KT 22A controller and LCD4 display, and a secondhand brick battery from some unknown medical or data center equipment.
My favorite layout is a sturdy nylon handlebar basket to hold the ~10 lbs battery, with the controller attached to the back of the basket. On others, I put the battery and controller in a rack top trunk. There are advantages and disadvantages to both.
Dual suspension and very large brakes ( super oversized vbrakes or 203mm disc ) is the bare minimum of what you want above 30-35mph.
These cruiser bikes aren't built with speed at all in mind, but mountain bikes are. A typical mountain bike will have both the suspension and frame strength you're looking for at >2x pedal bike speeds.
A MTB with dual suspension and proper geometry only starts getting skittish around 50mph. It's kinda built for that.
I agree with Chalo that a motor is best run near it's top speed.
These cruiser bikes aren't built with speed at all in mind, but mountain bikes are. A typical mountain bike will have both the suspension and frame strength you're looking for at >2x pedal bike speeds.
A MTB with dual suspension and proper geometry only starts getting skittish around 50mph. It's kinda built for that.
I agree with Chalo that a motor is best run near it's top speed.
I do not like Mountain Bikes that have been converted to motorized bicycles to use on the road because you have to lean over to reach the handlebars and it is not a comfortable riding position. The Townie on the other hand has a more upright comfortable riding position. Here is a Townie motorized bike I built. It had a Subaru 35cc motor and Kevlar Belt Drive. It would go around 30mph and had rim brakes and had no problems. Here is a picture of it when I took it up to the Mountains and cruised the Blue Ridge Parkway with it. The B.O.B. trailer hauled gasoline along with other items because there are no gas stations on the Parkway.
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docw009
10 MW
Looks like a single 20S BMS on one battery, cabled across both of them, so I think the 72V is no problem. other than being somewhat more fragile.
Stashing a big ass battery on a frame, and making it both look good and be structurally safe is always a challenge. Good luck.
I agree that having the power doesn't mean you have to be crazy stupid.
Stashing a big ass battery on a frame, and making it both look good and be structurally safe is always a challenge. Good luck.
I agree that having the power doesn't mean you have to be crazy stupid.
I ended up taking the Crystalyte 7240F controller apart to check for loose wires and bypass the switch to turn it on incase if it might have gotten wet and became faulty because it got left out in the rain. No loose wires and the switch is not the problem. The LED on the controller to show it is power on is still not coming on. Does anyone know what else I should check while I have this controller open? Thanks,
New results: I ended up unpluging the BMS and plugged it back in. Now instead of the Cycle Analyst coming on and shutting off in 1sec. It comes on and stays on. Also the LED on the controller now comes on and stays on. The problem I'm having now is no throttle control to the motor. The motor does not come on. What can I do or try to get the motor to turn?
Not sure what is going on now. I didn't do anything different. Now the Cycle Analyst and the Controller are not working now, where they were working before. When I plug the battery into the controller and turn the power switch on, on the controller, the LED power light on the controller comes on but fades away in about 3 seconds to completely dark. Does anyone know what is going on? I do understand what is going on. I have been repeating the same thing I did to get the CA and Controller LED light come on, by unplugging the BMS and the plugging back in, but it is not doing what it did in the previous post.
Update: This thing seems like it marches to the beat of its own drum. Ended up getting a little further with it. Got the LED on the controller to stay on and the CA to stay on. Now I unplugged the CA and only connected the thumb throttle to the controller. When I push down on the thumb throttle the motor glitches. The wheel will only move about a half of an inch. If I proceed to try and go to max. thumb throttle the system shuts down. Does anyone know what this means? Thanks,
Chalo
100 TW
The twitching behavior is characteristic of incorrect phase and Hall sensor wire connection, and the shutdown is characteristic of a problematic battery whose BMS is intervening.
ZeroEm
1 MW
I remember when that bike was used for melting motors. I took the idea of running a motor at top speed buy matching a motors Kv with battery voltage to get your top speed then half of that should be the slow cruse speed. Legal top speed for me is 27-28mph so my trike unrestricted runs a 72V battery paired with a 7T leafmotor and top speed is 32mph but trail speed is 15mph works out good.Dual suspension and very large brakes ( super oversized vbrakes or 203mm disc ) is the bare minimum of what you want above 30-35mph.
These cruiser bikes aren't built with speed at all in mind, but mountain bikes are. A typical mountain bike will have both the suspension and frame strength you're looking for at >2x pedal bike speeds.
A MTB with dual suspension and proper geometry only starts getting skittish around 50mph. It's kinda built for that.
I agree with Chalo that a motor is best run near it's top speed.
I took the eBike to a professional eBike repair shop and he did a diagnostic on it and told me that the controller was bad, but the battery and motor were good. He even offered to buy the battery and motor off of me so I'm not sure it is the battery.
slaphappygamer
10 kW
Some bike shops are funny. I get the feeling that if plug and play doesn’t work then they just replace things until it does.
That's because most stuff is locked out from programming, doesn't have good.. or any diagnostics. Doesn't have documentation. Doesn't have support.
Which is either a future liability or a current headache.
I like having full control over the things i own, and to have components that are supported by vendors.
So i'm solidly in the "replace all the electronics but the battery and motor" camp.
Which is either a future liability or a current headache.
I like having full control over the things i own, and to have components that are supported by vendors.
So i'm solidly in the "replace all the electronics but the battery and motor" camp.
Yea, The owner of the eBike store was cursing on the phone when I was speaking to him, so I'm not too sure how integral and thorough is diagnostic test was. That is one of the reasons why I decided to crack open the controller and look for loose wires.
The vendor of the eBike that the person I bought the eBike from purchased it from ElectricRider.com. Apparently they went out of business or were bought out and are now under the name Electroride. I tried to contact them and haven't heard anything back. It looks like replacing the Crystalyte contoller with a same mfg. maker would be hard. If I was to replace the controller, would Lyen or Kelly contollers be a good choice? What would be better?
Chalo
100 TW
Yeah, a bunk controller can do pretty much anything wrong, because it's the brains of the operation. But in my experience it's the least likely problem component except when the problem is sudden total death of the system. Almost always it's a wire or plug, next most likely it's one of the cheesy plastic peripheral doodads with moving parts, like the throttle or button panel.
Ended up taking apart the anderson plug that connects the battery to the controller because of what you said and also when I connect the battery to the controller with or without the anderson plug it throws a big spark, even when the controllers power is off.
It seems to be doing these three things now without no rhyme or reason: When I plug the battery into the controller, I either get no LED power light on the controller, a LED power light that is on but gradually decreases in brightness for about 3 seconds until it goes completely dark, to a LED power light on, on the Controller and the Cycle Analyst is on, but have motor glitches when I apply throttle. Any ideas of what I can check to address the above issues? Thanks,
