Mid drive or hub motor?

[phaseshift]

Hey everyone, I currently have an ezip kit conversion (450 watt) and I have been riding for a few months now and have decided I am hooked. I got it to walk my German shepherd originally, but every since I started riding the bike I have been riding my dirt bike less and less. I would love to replace my dirt bike with my ebike if possible. I am more interested in torque than top speed and I live in Florida, so there aren't many hills here. My main obstacle is sand, then heat. I have about 1000-1500 to spend total, the less the better of course. I have been looking around for a bit now and I was wanting some input by some more experienced riders....

Mid drive or hub? I seen an awesome dual motor cyclone setup with batteries and charger for about 1600, but can't find anyone actually using them.
Batteries.... I know I want a high amp battery vs a high voltage but I really have no clue about them yet. I see people hear build them, but I am wondering how safe the backpack batteries are.

My main riding would be trails, but I wouldn't mind using this to get to work (2 miles) if I can reach 35-45 mph. Any and all options are welcome, thanks ES

 

[Spicerack]

So many factors to consider.

Sand = ALOT of power so you're talking about a big set of tyres and a big battery pack. Using a mid mount like the gng or cyclone kits would probably be the go as you can use the gears and go slower through the soft stuff.

Speedwise, the gng or cyclone will get you there. There is a bit of a question on quality- the GNG kit seems to chew the belt drive once you turn the power up and people have been converting the belt drive to chain. Check out the GNG threads...

The problem with a hub motor for the offroad stuff is that it will always be a compromise. Slow wind for torque but low max speed- 25mph etc or higher speed for the speed you want. That will overheat in slow sandy stuff for sure. No doubt some people will challenge that, but you have to start looking at bigger more expensive, heavier hubs, modified for air cooling etc.

For your budget, you might get there- batteries will cost a bit and you may have to volt up a bit to get the speed you want. For the record, I've never used a mid drive kit, and only have geared/DD hub motors myself.

Good luck

 

[phaseshift]

Thanks for the quick reply. I was concerned about heat and the hub motor in Florida. I like the mid mounts but I'm confused on whether to go single or dual motors. I'm thinking the two motors will help with the torque situation. I see GNG has a dual 900watt kit and cyclone has the dual 2400watt. It looks like the GNG motors are closer to 1k watts after some research, which might make these the better deal as far as value. I can get the dual motor kit and controller for about $460 but there is little information on the controller or how many amps I can put into it.

 

[MadRhino]

Since you have no hills to climb, the heat is not so much of a problem. Building a good mid drive can be much more expansive and time consuming, maintenance and reliability have to be considered too. To ride on the sand, you want fat tires and a slow hub motor. Give it speed with higher voltage if you want. My choice would be a slow DD hub laced in a wide rim.

 

[pdf]

If you are willing to tinker a lot and don't require the bike to get to work, a mid-drive is going to offer low-end torque that most hub motor setups can only dream of. An electric bike for low speed trials and one that can do 45 mph are nearly mutually exclusive. If you really need to do both, I think you are talking about a lightweight electric motorcycle.
When you say low-speed, it depends on how low you want to go. 10-15 mph on a hub motor wound for proper efficiency in this range will be very do-able, but unless you put 120v through it, you aren't going to get near 45 mph.

Lastly, if you only need to go 2 miles to work, why do you need to go 45 mph? Is is a requirement for some other reason than time? Minimum required speed? Doing over 20 (assuming you are in the US) will disqualify this as a bike and depending on where you are, you could easily get ticketed. It is a bit of a stretch to fake pedaling at 45 mph.

I think I'd build one or the other first. Personally, I think really high torque, dependability, and low cost are one of those "pick any two" situations, but I am prepared to be proven wrong. You can add "45 mph min" to the mix, but if you want to stick with an actual bike, you can probably only still pick two.

 

[phaseshift]

The problem with the max speed is there is a 6 lane highway that I will have to travel down for those two miles with no sidewalks or access roads (FL sucks with roads). Also, on my way home I will probably be stopping by a friend's house (who I am converting to electric as well) and doing some riding before heading home. I see the dual cyclone motors can reach past 45mph easy (45 is my planned top speed until a nice custom suspension and front/back disc brakes are built) http://www.cyclone-tw.com/order-3chain.htm . After searching the internet I have only found 2-3 dual motor mid drive set ups and they dont really show much video. I am also wondering if the full kit from cyclone is worth it as well. I see a full dual motor kit with batteries/charger for 1600. I am thinking it would be better to get the dual motor setup and have someone here on the ES forums build a battery/charger. Once again, any and all opinions are welcome, thanks!

 

[dogman dan]

Actually heat is a problem in the deep sand. Lots of drag on that motor when you can't see the tire.

I ride deep sand in the dry streambeds here in the desert, and it can drag a motor down like you would not believe, if it's good and dry sugar sand. Then you forget about it because you weren't climing a hill. Next thing you know, what's that smell? Oh, look at the temp gauge, OHHH! fudge.

Same thing that works on hills will get you though the deep sugar sand, plus, the widest tire you can find. Abosolutely, step one is to get a frame that can take AT LEAST, a 2.5 inch rear tire. 2.3,is ok, but my bike does the deep sand so much better on a 2.5 than a 2.3.

Again, what works to get up the hill will work on the sand. Since you do want to go fast too, the huge hub motor and lots of power approach should work well. Lots of threads on it from many. It will cost some $$$. Can't get by with some funky 2c discharge rate battery, so read up on lipo to start with.