What sort of range and speed to expect from this kit?

[EX360G]

Hi

I'm thinking about buying a Mac motor and using it with a 36V 15Ah LifePO4 battery from Ping and I'd like to have a rough idea of what range and speed I could expect to get.

I'll be mostly riding on flat roads and slight hills but nothing major. I'll be riding in the woods a bit too as well though.

I'd like to know what top speed I could get without pedaling on a flat road, and a rough estimate of the range I could get with some light pedaling. It would also be interesting to see what speed and range I'd get if I went for a 48V 15Ah Battery.


These are the specs I think I'll be going for:

36V 15Ah LifePO4 Ping Battery
Upgraded 500/1000W Mac Motor from EM3EV
9 Fet 30A IRFB4110 controller
26" DM24 Disc (Rear)
320RPM 36V 8T Motor Speed

Thanks in advance.

 

[dogman dan]

8t mac should be able to go about 24 mph in a 26" wheel, on 36v. On 48v, about 4-5 mph more. That is not experience, but based on the charts on Pauls website.

But it seems to me, that 8t on 48v has been called a 30 mph motor, I just can't say where I think I saw that. More amps, would make a slightly faster motor in uphill or upwind conditions.

Range at 24mph, should be about 1 ah per mile on 36v, and 3/4 of an ah per mile on 48v. This is not maximum range, but a practical guide that includes a small reserve.

Max range of a 48v 15 ah can be 40 miles if you ride slow enough, but 18- 20 miles is typical, at the max speed near 30 mph.

If you pedal 100w worth, then go about 20 mph, 30 miles is quite possible from the 48v 15 ah. 100w pedaling will raise your heart rate, but you can still talk to somebody with no huffing or puffing.

 

[EX360G]

Thank you for the reply.

So at top speed on a 36V 15Ah Battery I would get around 15 Miles. I'll never be out for more than 10 miles at a time anyway and I'll always be pedaling a little bit so that's great.

If the 8T Mac really does 24MPH on a 36V battery then I don't think I'll bother going for the 48V battery. It's much bigger and heavier.

I'd like to hear from someone who has this motor on 36V battery to see if the 24MPH is accurate.

Thanks again for your help

 

[spisska]

I run this motor on 48V with a 10t winding and can hit 30. You have a speed winding in 8t, so I don't doubt you'll hit 24 mph even on 36V, though it may take a bit of time to get there.

 

[999zip999]

48V is very good to wake up a mac. 48V15ah at 25 amps or less. A C.A. is a plus you turn down your controller with it and the kit should have a three speed switch. For more range.

 

[dogman dan]

To be more clear, 1 ah per mile is what you can count on. You will often get more, up to 18 miles if you discharge it all. But to figure a battery size for a commute, you want to add some spare capacity.

So 1 ah = 1 mile for 36v works for that. With no more than 50w of pedaling. No sweat at all. And then much more if you ride less than 24 mph.

 

[teklektik]

So at top speed on a 36V 15Ah Battery I would get around 15 Miles. I'll never be out for more than 10 miles at a time anyway and I'll always be pedaling a little bit so that's great.

If the 8T Mac really does 24MPH on a 36V battery then I don't think I'll bother going for the 48V battery. It's much bigger and heavier.

I'd like to hear from someone who has this motor on 36V battery to see if the 24MPH is accurate.

Here's estimates 'by the numbers' - Justin's simulator gives accurate estimates and is handy for doing your own quick and reliable 'What If' estimates.

The run below assumes a Mountain bike frame/posture, 'typical' ebike tire (eg - not a road tire or slick), and a 170lb rider with 60lb bike. A BMC V2S is equivalent to a MAC 8T so we use that since the MAC is not in the simulator database.


The max speed is about 24mph and the max range is ~18 miles. The simulator may be a little optimistic about range and there are no adjustments for Depth of Discharge, so here's an excerpt from an Excel spreadsheet assuming an 80% DoD (rows for 36v and 48v batteries) just to verify the range using conventional recommended discharge practice.


Using the ~28Wh/mi energy consumption from the simulator, you should get about ~16 miles from the battery. There is little if any 'extra' for hills and headwind, but it sounds like this still offers you a good margin of safety for your planned 10mi journey. As we can see from the Load Line in the plot, the power needed to propel the bike at this top speed is about 525W. If you contribute 100W by pedaling, you can extend the battery range a bit without dropping your speed.

These numbers are pretty much in line with the recommendations above, but are based on actual dyno data and a little math...

Also FWIW - the controller with IFRB3077 instead of IFRB4110 FETs is a better choice for your build. You don't need the voltage range of the 4110 and are throwing away a bit of power as heat because of the higher Rdon spec. No point in paying more and getting less usable value in return.