MXUS 3000 sweet spot ? For off-road

[Jestronix]

I thought I'd check out what winding plus kW people are running on their setups for off road use. And if there is a sweet spot where heat isn't an issue but power is ample.

I'm running a 5T @ 4kw on a 26" and have virtually no heat, warm to touch with lots mixed hill riding. I'm hitting maybe 50kmh which on dirt trails is more thN enough for me. Motors up hills with no worries.

So the question is more power? I take it doubling power would come with some issues, heat and efficiency loss.

What are most using kW wise for their off road setups ?

 

[teslanv]

MXUS XF40-45H "3000W" Direct Drive Hub Motor Series:

3T:
Max. Continuous Phase Current: 55A
Overheat in 10 Minutes: 85A
Overheat in 60 seconds: 242A

4T:
Max. Continuous Phase Current: 42.6A
Overheat in 10 minutes: 66A
Overheat in 60 seconds: 186A

5T:
Max. Continuous Phase Current: 34.9A
Overheat in 10 minutes: 51.6A
Overheat in 60 seconds: 150A

6T:
Max. Continuous Phase Current: 30.3A
Overheat in 10 minutes: 47A
Overheat in 60 seconds: 132A

Generic Winding Phase Current Limits per strand:
Max. Continuous Phase Current: 2.84A per strand
Overheat in 10 minutes: 4.4A per strand
Overheat in 60 seconds: 12.4A per strand

*All data assumes a non-vented hub motor. Venting or other methods of cooling should increase these values.

If these values seem low, just remember that when accelerating from a stop, you might start out at very high phase current, but then in theory phase current would drop as you reach your cruising speed. - As long as your cruising (continuous) phase current is not higher than listed above, you would theoretically never overheat the motor.

 

[Jestronix]

Certainly this is handy, and have read through before. But more interested in user reviews, maybe a poll ?

 

[dogman dan]

I'll get hooted at again here, but I think a 5 t is not a bad choice for pure trail riding with a large wheel, or riding slow on a cargo bike you never intend to give more than 40 amps continuous. But perhaps in a motor that size, a 4t is plenty slow for trail use. It can take more amps, and would do better on open road you can haul ass on. I think lots of folks are riding the 3 t off road with no issues other than the speed at full throttle is ridiculous for a narrow trail. Just harder to ride trail with a throttle that has so much to give.

But if you want to up the amps and go faster, it's clear that you want the faster winding for that. But I would not worry about 60 amps controller with the motor you have, simply because your winding won't let it pull 60 amps for long, unless you are climbing a real wall. Chances are, you don't pull more than 30 amps, except for briefly. Bottom line, you don't spend much time stalling a motor that big.

So depending on what you want, and the amps you run now, you might just be on the sweet spot for you. It just won't be the sweet spot for others.

 

[MadRhino]

Certainly this is handy, and have read through before. But more interested in user reviews, maybe a poll ?

You will find that riders are very different in their riding preferences. I ride a slow motor in the mountain when it is wet and dirty. On nice hard pack I prefer a fast motor. Since I feed them with 24s RC Lipo and all the power that a motor can pull, the slow one does 86 Kmh and the fast well above 100. Then, many just can't ride that fast, wether their trails are not clear enough or they sh*t themselves out with the big trees each side whipping the hair on their forearms. Most fellows I ride with, would be very happy with half the speed I carefully ride to give them a chance to follow.

The limit of a motor is dependant of the weight, wheel size, inclines, and rider behaviour. Start with knowing yourself and your bikes, fry a few, then you will know your own motor limit.

 

[Jestronix]

Thanks guys ,

I think for now 4kw is plenty on a normal dual MTB not a flux etc. I hit 60amp a fair bit but briefly and certainly not creating much heat. Speed wise I'm not real comfortable going much faster on this frame. Only thing I might do is jump up to 18s rather than the 16s.

 

[markz]

18-20S is the sweet spot for these MXUS 3000W motors. You can dial up or down your voltage for the speed you want, but give it a tad more volts and up the amps. Then reduce the diameter of your wheel, especially with the 5T, go to a 20 or 24" diameter. Then you will be in the sweet spot for SURE!

 

[Jestronix]

I'm gunna step it up to 18s and see how we go. RC lipo at the moment. Lacing will cost a bit to drop down, stuck at 26" for now.

 

[TotalConfusion]

Ive got myself a 5T and im putting it in a 18 inch Moto rim and i have the 18 x 2.75 tire already and sitting it next to my 24 inch Hookworm the 18" is almost exactly 1 inch smaller than the 24" hookworm, I went a 18 because its quite Hilly where i ride, not mountains but small steep 2 to 300 metre long hills and i thought the slightly smaller rim would help for over heating, I plan on buying the Adaptto mini-e on 65 battery amps for mine.

 

[Jestronix]

How do u find the handling on the 14 ? Ride height must introduce some interesting situations.

 

[markz]

Ive got myself a 5T and im putting it in a 18 inch Moto rim and i have the 18 x 2.75 tire already and sitting it next to my 24 inch Hookworm the 18" is almost exactly 1 inch smaller than the 24" hookworm, I went a 18 because its quite Hilly where i ride, not mountains but small steep 2 to 300 metre long hills and i thought the slightly smaller rim would help for over heating, I plan on buying the Adaptto mini-e on 65 battery amps for mine.

Keep us and me, updated on your findings of going smaller wheel with your 5T. I currently have a 4T, and am thinking about going smaller diameter wheel also. It will cost me ~$150 to go this route, which is a lot of money to go smaller diameter wheel.

 

[dogman dan]

I'm not sure 20" bike wheel will ever be the sweet spot for off road, unless you live where rocks and roots don't exist. It damn sure can be for street though.

But for sure, it could be very sweet to go to something much smaller than 26" bike wheels, in a moped or motorcycle tire for the rear tire. Once you go big power, it just seems like a good tire lasts about a month before it starts to fall off in ride.

I need to do this with my 5304 motor. I've gotten my strength back, and riding hard and fast again. Still happy with 30-35 mph max, and running 48v simply for economy. But I need a tougher rear tire for blasting around at 25-35 mph on razor sharp desert rocks.

If I really had my druthers though, I'd get a slow but powerful electric motorcycle. like an Osset.

Re the buddies keeping up, I consider myself a pretty slow rider. But with home trail advantage, I was twice as fast as some guys riding 10,000w bikes. I was packing 48v 22 amps, 1000w. When I rode the same bike, I could barely stay on the trail. It needed a throttle tamer real bad.

So just saying, depending on the trail, more may not be better. Yesterday I had a blast riding roads on my fast bike, drifting corners fun. Today I'm just about to go have a blast riding the slow bike on singletrack.

So what I mean is one bike will be sweet on one ride, another sweet on a different kind of trail or road. So like many of us have, multiple bikes may be the real answer to the sweet spot.

It sure feels great though, to go for a long hard ride and not feel bad afterward for three days. I'm back in the saddle again!

 

[999zip999]

5t for local hills on the street or on the beach at low tide. 80v and 40amps with a 12 fet em3ev controller. It will go 39mph and 25mph on most hills. It only gets a little warm. It works great.
I would like more amps but will wait till a good sine wave coentroller at 80 amp. or get my lyen 12fet fixed and see how high he can turn it up to.
It's heavy and so is 24s of lifepo4 A123, a tank. I'm be scared to have a faster bike for street bike as I ride wot al the time.

 

[Sean9002]

I'm not sure 20" bike wheel will ever be the sweet spot for off road, unless you live where rocks and roots don't exist. It damn sure can be for street though.

20s are a good choice for the rear on rocks if you have the correct tire like a moto trials tire

 

[MadRhino]

I'm not sure 20" bike wheel will ever be the sweet spot for off road, unless you live where rocks and roots don't exist. It damn sure can be for street though.

20s are a good choice for the rear on rocks if you have the correct tire like a moto trials tire

Good for traction, yet still a bucking horse.

 

[Jestronix]

Upped it to 75v @ 60 amps and I'm stoked fast enough for now ....... Very very light front end , time for a 5t on the front too ?

 

[Jestronix]

Went for a ride with a mate today, lots mountain bike tight twist banked turns , rock gardens and tree roots etc. he was way faster than me with no motor on his giant anthem, my biggest problem wasn't power it was agility. The weight in the rear wheel would be a lot of it, centrifugal forces at work, battery pack is only 2.5kg and it's located under the top bar.

Soon as we hit any type of open trial it was game over for him as expected. I'm hoping moving batteries lower will help, I'm thinking front bar is best.

60a @ 75v was plenty, the look on a joggers face as I punched up the dirt trail doing jumps at 40 or so was priceless as was the grin from me . I think I get more enjoyment on an electric bike than I ever did with motocross. Motocross is violent and freaky when things get out of shape, the quiet and access to bike trials and other locations is better.

More power? I think I'm happy for now, however 80amps @ 80v might be on the cards soon, it may be too much though.

 

[rider95]

I wish ppl would put were they live at , thinking about using this hub motor for my next build .