Some questions for an Electric ATV Build

[Nerdengineer]

So, I'm an electrical controls engineer, I own a Surron bike and love it. My friend has decided he wants to build a street legal electric ATV and has asked for my help.

I'm 100% comfortable Wiring, programming, etc. But I don't know what is the most reliable setup.

We have decided to shoot for a top speed of 60-80mph and a range of 50-60 miles. This won't be used off-road, only on paved streets, but we live in Colorado Springs and nothing here is flat so the range will definitely be affected by that. It will obviously be a chain driven rear axle and street tires will be put on the bike.

I've narrowed it down to the ME1507 or the QS180 for motors. Is either brand/model better than the other in areas? Is either of them more reliable than the other? Is one more available than the other? is the water cooling on the ME1616 worth it? And if it's water cooled what type of pump do I need to run it and how much would that cut down on the range?

Controllers, there are so many I can't narrow it down. We'd like it to be bluetooth capable to use a phone to change some options here and there. The easier it is to program the better. While I will be doing the initial programming/tuning, I will need to show him how to do it as well in case he has to change something without me.

Batteries - Here's the deal lol. I know how to and can build battery cells, but I'd prefer not to. He is perfectly okay with ordering a pre-made battery setup and that's what I'd prefer as well. Any reputable suppliers you guys know of? I'm thinking 72 or 96V with a decent Ah rating for range.

Display - He wants a nice display that can show a lot of data, mph/battery/range and so on.

Any and all suggestions would be appreciated. I spent some time going through the forums and instead of narrowing things down I ended up expanding the list of items I'm interested in lol.

I'd like to order as much of it as I can from the same place, but if I have to piece it together I'd like to get things that play well together to avoid too much frustration.

The ideal situation is to be able to grab a motor, controller, battery and display from as few locations as possible and that all play nicely together.

Thanks in advance!

 

[amberwolf]

We have decided to shoot for a top speed of 60-80mph and a range of 50-60 miles. This won't be used off-road, only on paved streets, but we live in Colorado Springs and nothing here is flat so the range will definitely be affected by that. It will obviously be a chain driven rear axle and street tires will be put on the bike.

Batteries - Here's the deal lol. I know how to and can build battery cells, but I'd prefer not to. He is perfectly okay with ordering a pre-made battery setup and that's what I'd prefer as well. Any reputable suppliers you guys know of? I'm thinking 72 or 96V with a decent Ah rating for range.

Here's the thing...that's going to be a pretty big battery.

At 80mph, I'm going to guesstimate without checking a simulator that you'll need at least 150wh/mile on a flat road--an ATV's not likely to be very aerodynamic, so at higher speeds you use a lot of power just to overcome air resistance. If you're going up hills, the power demand goes up quickly (similarly, more power for riding against headwinds).

60 miles x 150wh/mile = 9000wh, which is a pretty big pack. If you used 96v, then just round up a bit and call that 100Ah. I have a 52v 40Ah (14s2p) 2kwh pack on my trike, and if it were in an enclosure instead of more or less bare cells in their holders, it would be close enough to 40lbs, and roughly the size of a stack of hardcover books a foot high. A pack to do that speed and range (on flat roads!) will be roughly four and a half times that size and weight.

That doesn't account for hills, winds, detours or poorer-than-usual conditions, or aging over time; if you need to still get that speed and range under those conditions, the pack will be bigger and heavier. If the hills are steep enough, it could take twice the power (or more) to do the work, and thus take twice the battery size to handle that.

There are various simulators/calculators out there; I usually use http://ebikes.ca/tools/simulator.html to do guesstimates. It's designed around ebikes, but you can use the instructions there to play around with it using "custom" settings (rather than presets) for motor, controller, battery, etc., and put your riding conditions in, to get estimates of power usage, etc. for each different set of conditions.


Also, the heavier the battery pack is, the more it contributes to overall vehicle weight, and the more power it will take to go up the hills, needing an even bigger pack to do the same range.

The estimate above also assumes you're going to use *all* the pack's capacity, which means it ages faster, and lasts less time and usage cycles. (using less of it's capacity, meaning charging it not to full, and discharging it not to empty, helps the cells last longer--the closer to the middle of it's SoC range you stay at, the more cycles and time the pack will last).

Display - He wants a nice display that can show a lot of data, mph/battery/range and so on.

Cycle Analyst v2.x from http://ebikes.ca will do that sort of thing well enough (and other things, the v3.x even more if you need it).

If you want something fancier, or more graphical, there may be other single-device solutions out there; depends on exactly what you want it to do and look like.

 

[Nerdengineer]

Yeah I knew it would be a big battery. It will likely never really be going 80mph, and 65 would be the most for short periods of time.

It will be on an ATV Frame, likely a raptor 660, so there is some room there.

It will mostly be going around 45-50mph or less in city driving conditions. So I think the range is doable knowing that at max speed he will have significantly reduced range.

 

[ZeroEm]

Would build for your 65 mph and pack as much battery in your space. Range depends on conditions. If planning on a long ride keep the speed down. The slower you go the farther you go.

by Nerdengineer » Sep 19 2022 8:04am

Yeah I knew it would be a big battery. It will likely never really be going 80mph, and 65 would be the most for short periods of time.

It will be on an ATV Frame, likely a raptor 660, so there is some room there.

It will mostly be going around 45-50mph or less in city driving conditions. So I think the range is doable knowing that at max speed he will have significantly reduced range.

 

[PaPaSteve]

15 ~ 16 years ago I did the fabrication work to electrify a Kawasaki Bayou 250
The customer bought the electric parts from Thunderstruck.
Pretty sure the motor / controller was the 48V AC-9, Curtis controller powered by 15 CALB 72ah batteries.
Customers use was off-road farm duty where it seemed to be ample capable and maybe too fast.
Above 72V there are limited options for pre-built battery packs.
Besides browsing the Thunderstruck site also peek in at EV West.