Essentially, A lot of people build boards, but the quality of materials and the engineering of the electrical system is very important. If you want your electronics to last, you need to keep heat down. Heat kills electronics. The by product of drawing amps is heat is generated. So this is why higher voltage (10s or 12s) is recommended. The problem with higher voltages is that there’s not a lot of hobby grade escs that can do 10s or 12s. And the ones that can are usually around the same price as the vesc anyways.
Theres a lot of details that you must pay attention to if you want your board to last. If your an electrical engineer and really understand this stuff, you can build a board for under $500 USD (which is what, like $350 euros) if you already have the tools you’ll need (i.e. soldering iron, heat gun, hot glue gun, jig saw, maybe 3d printer and/or cnc milling machine). But it’s hard to do because hobby grade escs and motors will blow up if you put too many amps through them. Knowing how many amps you will draw determines the gauge of wire you should use, the esc, and the motor. It may also determine if you need at least 2 motors (or in my case, 4 motors). And there’s no way to know becuase theres no formula that allows you to plug all of the variables that will determine this (even little things like the duro of your wheels will affect range and amp draw).
We call this the false economy. You think your saving money by buying the cheapest parts you can, but unless you buy exactly the right parts you need considering your riding style, weight, and the terrain you’ll be riding in, things will blow up and cost you more money in the long run. I feel into this trap, as many others (including Jason from Enertion) have.
Higher amp (and voltage) escs and higher amp motors (i.e have thicker gauge phase wires) are more expensive. There’s no sensible way to control amp flow of a hobby grade esc. You can change settings which in turn limit amps flowing to the esc or to the motor, but they give them names like acceleration, and have values like high, medium, or low. There’s no mathematical/scientific way of knowing what the actually numbers are, and thus, your likely to blow up escs and/or motors.
This is why the VESC is highly recommended. You can control whats happening and protect your electrical system. You can prevent ESC overheating, pulling too many amps from your battery (which could destroy your battery and/or esc), pushing too many amps into your motors (which could destroy your motors), and many other limits.
If you don’t have your electrical system engineered correctly with proper gearing, you will be able to ride at first with little to no issues, but something will blow with in a few weeks (or when you push its limits on hills). If your macanical system is not engineered correctly, belts constantly breaking will be the least of your issues.
A properly engineered system should never break, but the reality is, most are riding systems that could be improved with proper engineering.
The other thing is, many will try to convince you that you can go the keep route without issues. There’s only a handful of builders that I know who have done this successfully that use their boards to commute like this. I know because I commute over 50 miles (or 80km) per week, and have built many boards cheaply that do this. Many with cheaper setups don’t ride very often and/or live in flat environments. If you expect to go up hills, understand what effect that has only the max amps you need your esc to be capable of drawing (will likely double or triple it).
Even buying a vesc, not all vescs are the same. Chaka, for example, has upgraded his vescs so they are more robust. Many have had issues with enertion or diy’s vescs. You want a warranty on something like this, because if you buy two (like I did) and one comes broken and the other breaks on day 2, your out a lot of money. again, the false economy of thinking you can save a few bucks for something that looks exactly the same, but are not.
My recommendation is, don’t build your own board because you need to save money. Build your own board because you enjoy the building process or because you want to build something more robust and powerful than what’s already on the market. Because the odds are, you’ll spend at least twice your original budget before you have board that works for more than a few weeks.
Most people don’t need what I’m riding right now, but being DIY, and having engineered this board correctly before building it (based on testing and data I’ve gathered in the past), It still came out to a little more than $1800 USD (or $1615 euro). A good DIY board should cost in the range of $1000 USD to $2000 USD. You can build a good board for less, but make sure you have the knowledge and know what your doing, or you will waste a lot of money. I don’t know many builders that have successfully built their first board for under $500, that actually get the range your looking for.
Also, you need way bigger batteries than 5 Ah if you want the kind of range your looking for. A minimum of 10 Ah if your a light guy and riding on flats, higher if your more than 150 lb and want to ride hills. On my first board, After blowing up 3 ESCs and 3 motors (one being an expensive r-spec due to too high of the acceleration parameter setting in a hobby grade car esc), 8000 mAh could get me about half the range your looking for. Given, it was on 6s, not 10s, but even the space cell (which is 10s at 7500 mAh or 10000 mAh) won’t get you that long of a range. For that kind of range, you need at least $250 eruo in batteries alone…