kevinkelley702@gmail.com said:
The ebike would be my daily commuter to and from work, 8 miles round trip. I figured $200 for an ebike what could go wrong, the fact the the company is no longer in business and you can't find parts for them is the problem. I have gutted all the electronic parts and wiring and has turned a $200 bike into a $200 in parts not including the battery yet, nightmare. Replacing all the old wiring, controller which was inside the downtube and new display. In all I have decided to finish the project, but next time I will just by a bike and a conversation kit. It would be a hell of a lot easier the to upgrade a factory built ebike.
Unfortunately, that's generally true. Most used bikes, if not fully working, even if they were DIY conversions rather than OEM, will require significant DIY work to adapt parts, or replacing significant amounts of the original parts with new ones just to get them to work together. (sometimes you can make a system work without some original part, like the display, by wiring around the power-on control so it is always on when the battery is installed, but you then lose the ability to change from the default assist levels or any other default settings in the controller at power-on...sometimes that is fine, and sometimes unusable).
Sometimes the parts you know you can still use on it are worth the money and trouble of replacing those you can't, but this is fairly rare.
Any system (OEM or DIY) with a "dumb" headless controller that doesn't have a display is going to be a lot easier to deal with than one that requires a display to access settings/assist levels/etc., though the headless controllers like that don't have any options or settings (that a user can change), so they are what they are at power-on.
Which system to choose depends on the usage it will be put to...for throttle-only usage, headless dumb systems work perfectly well; for typical pedal-controlled (PAS) systems it's helpful to have a way to configure the assist levels. Then there are the more advanced systems like using a Cycle Analyst from http://ebikes.ca to read all your sensors and process the inputs via your settings to run a headless dumb controller pretty much exactly the way you want it, or the various FOC controllers that are highly configurable via apps or computer-based setup programs.
kevinkelley702@gmail.com said:
Battery will need to be replaced with another 36v maybe a 48v with 10ah as not to overload he 36v 500watt motor. 48v×10ah=480watts. I could go with a 48v 12ah which would be 576 which isn't too much for the motor. But a 10ah will be just fine.
There are a few misunderstandings above:
--a battery does not overload a motor; the motor can overload the battery (or rather, the load placed on the motor by the riding style, terrain, wind, etc can cause the motor/controller system to overload the battery). Depends mostly on the load, and on the controller's current limit.
The battery will need to be whatever voltage the controller requires. If it's not high enough voltage, the controller will not operate, as it has a safety feature to prevent draining the battery too far (LVC). Note that the battery voltage, when at full throttle, directly affects the top speed of the motor assuming no speed limiting in the controller. So a 48v battery will spin a motor proportionally faster than a 36v battery, by the ratio of 48:36, giving a potentially faster top speed assuming no controller speed limiting and assuming enough power (watts) to the ground from the wheel to go that speed on your terrain, wind, and aerodynamic air resistance. (you can play with the simulator at http://ebikes.ca/tools/simulator.html to see how this can work).
Watts isn't determined by Ah (which is only capacity). It is determined by Amps (current), x Volts. The battery may have a maximum continuous current (A) it can output, and a peak A. You would determine Watts by the continuous A x the average (nominal) battery voltage (48v or 36v in the example cases).
Capacity (Ah) you need is determined by how much range you need, and how much current you draw during the ride. It's usually done with Wh rather than Ah, so you multiply the Ah x the voltage to get the Wh (which is also capacity). Typical pedal-speed operation in the 10-20mph range on flat ground with no wind is in the 10-20Wh/mile range (sometimes less), depending on how much you contribute to power by pedalling vs how much the motor does. If you have hills, wind, or ride faster, or like to accellerate harder and/or don't pedal at all, power usage can be a lot more. Not knowing your usage, riding style, terrain, or winds, we'll go with 20Wh/mile.
So for 8 miles of range, plus say 50% (4 miles) to account for potential detours, headwinds, and pack aging over time (which loses capacity over the years), that would be 12miles x 20Wh/mile, or 240Wh. If you have a 48v battery, that is 240Wh / 48v = 5Ah. A 36v battery would be 240 / 36 = 6.7Ah.
That's assuming you get a good quality battery from a reputable seller that can output high enough current without straining the cells; a cheap battery is unlikely to do that (it's cells are cheaper, sometimes not new, usually not matched, and generally less capable). You don't specify what your new controller is or link to it, so we'll just guess that it has a 20A current limit to approximately match a 500w motor on a 48v battery. If it pulls a max of 20A, then when you are riding at a speed under conditions that require enough power, the battery must be able to supply that 20A without being stressed. A 5Ah battery would have to be a "4C" rated battery (pretty good cells, though not the best out there), to do that when new (as it ages it gets less capable, so a 6C+ battery might still do it as it gets old). This is where it gets a little confusing, because I said Ah isn't amps...but in this case, A is derived from Ah by multiplying by the "C" rate of the battery, so 5Ah x 4C = 20A (loses the "h" here).
It's usually cheaper to just get a bigger battery, so a 10Ah or higher would probably be fine, since even most cheap cells can do 2C (which would give you 20A capability with a 10Ah battery when it's new).
There may be other considerations, depending on your riding conditions/etc; you can play with that simulator linked above to see how things interact with each other.
My problem now lies in the connection between the controller, which is the juliet motor connector to the motors higo connection. I have looked online for adapters which I have not found a juliet to higo. So I think I either make one myself or take the motor in a shop and have them replace the higo with a up-to-date juliet connection.
Note that it is "Julet" not "Juliet", which may aid your searches...but to make it more confusing, sellers often use Julet and Higo interchangeably, so looking for the specific "connector part number" may be better. This page has the major ones listed here:
https://ebikes.ca/learn/connectors.html
I'm going to guess the controller has this one
HiGo Z910
https://ebikes.ca/learn/connectors.html#HiGoZ910
but there are multiple types that fit your description of the motor end.
If you can't find the cable you need, you may be able to have ebikes.ca make one for you, or you can order the matching end to plug into the motor and change the cable on the controller to match (it's easier to open and solder inside the controller than the motor), or you can cut and splice somewhere in the cable itself for either motor or controller with the matching end for the other one.
For splicing, these are handy:
https://www.amazon.com/gp/product/B07R4Z13P3
I'm sure there are smaller cheaper kits with just the sizes you'd need for the specific wires you need to connect.
I recommend you stagger the connections so they are not next to each other; this will both make the total cable thickness at the splice smaller, and help prevent shorts between splices should insulation on them fail or any of them ever come undone.
https://trucktractor6x4.tpub.com/TM-9-2320-302-20/img/TM-9-2320-302-20_187_1.jpg
TM-9-2320-302-20_187_1[1].jpg
Then you can use wrap like this to seal the spliced area against weather
https://www.homedepot.com/p/Nashua-Tape-1-in-x-3-33-yd-Stretch-and-Seal-Self-Fusing-Silicone-Tape-in-Black-1743082/100206050
there are a bunch of variations of that kind of thing.
(the links above are just examples; you can probably find better deals or better products).