hightekbikes.com motor kit review. Electric bike kit.

[RTLSHIP]

Mr. Dogman, what has gone wrong with your Aotema kit since Jan. 2009? Controller, spokes ?
You suggested that you would ride hard and not sugar-coat anything.

 

[dogman dan]

Nothing whatsoever has gone wrong with it. I just keep getting sent other motors to test, and this one has 2000 miles on it. I did try to melt it the summer of 2009 and never got it above about 180F all summer, while climbing 1000 vertical feet to my house on 100F days. We had a cool summer though, no 110 days to speak of.

I recently trued the rim and took it to the Spooky Tooth death race, and ran it all afternoon WOT in 90f weather. Managed to beat about 4 gas bikes in the main event. Next year I'll be running a 72v controller, but I may want to upgrade the rim for that. I may just run a 9c though, it just depends on which one can accelerate from 30 mph to top speed quickest. I'll be looking for the fastest top speed after 700 feet, the length of the long straightaways on the track. Whatever motor I run will get modified, big wires, big holes in the cover, etc.

 

[RTLSHIP]

You suggest that this hub motor can handle 72v but that you need a different controller and, for racing purposes, a
stronger rim etc. Moving up in voltages gets expensive--- battery and controller wise. I guess if you have sponsorship it's not a problem.

 

[dogman dan]

We'll see if it can handle 72v. Es donations did buy me the controller, but from Lyens it wasn't all that expensive. I'm not sponsored too much for racing, but it would be nice to be factory rider for somebody. I'll need at least $600 in lipo to get going, but to race all afternoon I may need closer to double that. Racing is gonna cost me, but I live too close to the Death Race to ignore it. I love cornering hard too, so its a love match.

As soon as I get a bike assembled to put it on I'll start testing the heating at 72v, and see if 30 min of racing is possible. No doubt, I'll need to modify the motor with the usual stuff, vent holes, big wires etc. I did promise Terry I'd try to melt the motor, so maybe I finally will.

In a way though, I am sponsored for racing, last time I paid for a new motor was about 18 months ago.

 

[RTLSHIP]

I bought a 6 FETS controller from LYEN. This should allow me to run at both 36 & 48v without having to worry about overvolting. Even though the Aotema stock controller has 63v capacitors doesn't mean other parts of the controller can handle anywhere near that amount.

 

[dogman dan]

When I soldered the shunt on one of my stock HTB controllers I got it up to 30 amps. Terry told me I was near that controllers upper limit, and sure enough, the first time I rode it in temps above 85F it started cutting out from the overheat. Now I have a winter only controller. I ran a stock one in the death race with no problems though, and it was near 90f that day. Next year I'll be running the lyens sensorless 72v 45 amp controller in the race.

 

[easieSTrider]

I have 200 miles now on the Aotema hub with no problems with the motor or controller. I have changed out the big ugly rim and relaced with a 700c x 36h Alex Adventurer rim and 35c tire, so now it looks more like a stock Trek. Remarkably I gained 1mph to a steady 24mph now. I love this thing for my 9 mile commute to work. Thanks to Cycle 9 for the 220mm 2.3mm butted spokes and Niagara Cycle - awesome fast delivery from both.

 

[The Mighty Volt]

I have 200 miles now on the Aotema hub with no problems with the motor or controller. I have changed out the big ugly rim and relaced with a 700c x 36h Alex Adventurer rim and 35c tire, so now it looks more like a stock Trek. Remarkably I gained 1mph to a steady 24mph now. I love this thing for my 9 mile commute to work. Thanks to Cycle 9 for the 220mm 2.3mm butted spokes and Niagara Cycle - awesome fast delivery from both.

Hi, can I ask what battery you are using with it? I found the Aotema to be neat and understated, with quick delivery and an excellent service from HTB. On the downside, the motor was a bit asthmatic when mated with my 36v 20Ah Duct-Tape. At peak, the motor drew 26 Amps and the controller was warm, but not hot, to the touch. A very civil piece of kit, it is ideally suited to the urban commuter who lacks tech know-how.

 

[easieSTrider]

I"m using the 36v 15ah battery as supplied by HTB. Yeah, it's a tame motor just right for this low tech fatass commuter. I've got too much other crap in my life that fail me... like weed wackers, motorcycles, coffee makers, laptops, politicians, warm beer, etc., that piss me off to no end. This kit works just fine, Thank you.

 

[dogman dan]

Faster wind motor doesn't spin up off the line as good as a slower wind, but I wouldn't call 24 mph cruiseing speed asthmatic. But I do find that the motor does start to stall a bit starting up, and learned to use half throttle for a few feet, and then punch it.

But it's a lot funner ride at 48v for sure, with better response off the line and 29 mph speed.

 

[The Mighty Volt]

I"m using the 36v 15ah battery as supplied by HTB. Yeah, it's a tame motor just right for this low tech fatass commuter. I've got too much other crap in my life that fail me... like weed wackers, motorcycles, coffee makers, laptops, politicians, warm beer, etc., that piss me off to no end. This kit works just fine, Thank you.

Thats just it. You cannot go wrong. Sensorless is so neat. I am too heavy for it myself.....I referred to it as "asthmatic" in comparison to the really dirt cheap but inherently more unreliable hub I got off ebay. That hub had a wider diameter, and probably pushed out more torque as a result.

 

[The Mighty Volt]

Faster wind motor doesn't spin up off the line as good as a slower wind, but I wouldn't call 24 mph cruiseing speed asthmatic. But I do find that the motor does start to stall a bit starting up, and learned to use half throttle for a few feet, and then punch it.

But it's a lot funner ride at 48v for sure, with better response off the line and 29 mph speed.

Yeah, it could grind and jam savagely if I was too smart with it. But thats perfectly normal for sensorless, you have to be smarter than the tool to use it, as I found out. I dont think 24mph is slow, its just with a 26" wheel, a Fat Frank tire, a heavy rider, rubbish roads and a constant wind in my face, it simply took too long to reach 24mph. The Aotema lacks the torque of other wider hubs, which is perfectly OK, it is not advertised or priced as being animal in terms of torque. Of course, at 36v of Cammy brilliance, the motor was probably not being given the best chance. :lol:

Out on the highway, with cars cruising past faster and faster, and with a lack of perspective because of the openness of the road, it did feel slow.

In Urban settings, with the buildings on the street giving perspective and with overall speeds much slower, it felt really good and allowed me to compete with motor cars, that is to say, I felt comfortable out in the street and did not feel obliged to hug the kerb. I cannot recommend it enough to users who dont like mounds of wires or complicated molex arrangements. The kit was top notch and had loads of little added extras like hex keys, heat-shrink and a spoke adjuster.

 

[RTLSHIP]

I like this hub motor, especially when considering the modest price. The controller can always be
replaced for something better/stronger or more efficent.
If anything can go wrong, it's likely with the controller. Also, cut wires near axle can cause problems. My hunch is that the hub motor will just keep going for many years. The main motor maintenace issue is the bearings which can be lubricated. Will this motor still be high tech 10 years from now? Maybe.

 

[easieSTrider]

You two guys bring out some of the arguments (good & bad) about this motor kit. As a new rider I could recommend this to anybody with the same goals as I had, that is being reliable, somewhat fast, assist on small inclines, against the wind, and cost with LiFePO. Relacing to a higher quality rim and narrower tire were sure worth the effort IMHO. Now that I've ridden on & off for about 2 months now I can see the pro's & con's that I would reconsider for a next build. But hey for just getting into this stuff I'm plenty satisfied with the unit. It's a learning curve and educational trip for sure and you guys help alot.

 

[craiger_ny]

I picked up a kit from Hightek a few weeks back and also a 36V 20 Ah LiFePo4.

As far as the order is concerned I received a notice that Hightek got my order and a notice when it was shipped from Terry at Hightek. Dogman pretty much laid out the packaging so I won't re-hash it. Packaging was very good. Single wall rim identical to the ones on the beach cruiser style bike that it went on. It came with brake levers with cut offs which I can't comment on as I have not utilized. The controller had a cover on it that was not seated. Upon further investigation the board inside was protruding maybe a eighth of an inch or so preventing the cover from seating. I took it apart and slotted the holes in the housing so that the board would sit back beyond the cover. It should be noted that Terry did not hesitate to offer another controller. It was an easy fix so I declined. Also included were zip ties, cable covers and a spoke wrench. Finally a battery bag with Velcro straps was also included along with some bungee cords. The battery bag is exactly the same dimensions as the battery and is quite secure when fastened down. I do plan someday to mount a hard case but the fact that this was included was great because out of the box I was up and running. That was a nice plus. Documentation was good and Hightek's website also makes sure you have the info you need as a first time buyer as well.

I was holding off on posting until I had a chance to run the battery down a good run but have not done that yet. I ride a Trek beach cruiser style bike with this kit. It typically pushes me at 22-23 MPH on the flats WOT without pedaling. I have ran it this way for 16 miles non-stop without it cutting out so all I know is my range without pedaling is beyond that. I will run it down one day and revisit this thread to let you know how I make out. I have e-mailed Terry about charger options and it looks like if you want you can buy various chargers from him as well. My battery came with one.

The negatives would be the controller cover issue. Simply aesthetic and fixable. Like I said Terry was fast to offer a fix. Bungee cords were cheap and I have plenty of those myself so to be honest the kit could be without those but I can see how Hightek would add that to make a nice touch on the kit. Positives far outnumber that. Hightek communicated about the order well and responded right away to my e-mails. Packaging was great. The kit is literally complete enough to ride right away. With the battery bag, cable covers and zip ties you don't really need to buy anything on your own. The wheel was true and spokes tensioned well. This is my first e-bike mod so I can't really give any testimony that compares to other motors but I am satisfied with the performance. As far as a business goes it was a pleasure to deal with Hightek and I will not hesitate to do business with them in the future. I wish them well and as long as they continue to focus in the manner that they are I am sure they will.

Craig

P.S. Don't let easieSTrider fool you about things that fail. His wife is the family breadwinner, he has it made. Dude just sits on his ass all day. Why do you think he electrified his bike?

 

[easieSTrider]

Nice write up there Craiger. You have done an exceptional job of explaining the kit from HTB. The only exception I have to take is in the post script. You know that I am a wall street hedge manager over compensated by 350 mil a year plus bonuses, and if i was to cruise around in my Bently Continental gtc I would be busted. There's nothing wrong with being a little thrifty with my money and the Aotema hub kit is an excellant choice for any entry level e-biker. Now if i could only get the wife to share that multi-state lottery winnings...

 

[dogman dan]

Sure that wasn't me you meant? About the wife making all the money? Anyway it applied here too. I sill work hard every day, but haven't been able to do an 8 hour day since my back got ruined 16 years ago. So I end up back home by noon most days, with only a half days pay.

Well being slow and seeming slow are two different things. From 0-25, at 48v my 9continent gets to 25 faster, and climbs a hill better. But when I wanted to race, I chose the Aotema for it's faster top speed. Not tons faster, but it could hit 30 with light pedaling, where the 9c needs a sprint to reach 30. It seemed like I was faster than about a third of the field, since they were behind me.

Any faster winding motor will behave that way, slower off the line, and hitting that butter zone of the amps drawn at a higher speed. The last 5 mph is slow to come on any motor, since the amps drawn begin to drop then as you approach no load speed.

 

[easieSTrider]

Happy Memorial Day.
I guess I do not understand the "no load" speed. If the motor is tapped out, counting rolling friction, wind resistance, wattage, mass, etc., would'nt I be at full load speed? Like I said before I'm still learning. Either way a good motor for my application. I just wish I had the luxury of having several motors & bikes for any occasion.

 

[dogman dan]

As I understand it, it has to do with the way the tourqe curve of electric motors graphs. At zero rpm, the motor has it's maximum tourqe. As the motor gets going, you reach a peak in wattage, but tourqe is already going down. Next you reach no load speed, which is the fastest the motor can spin with no load on it. So nobody is riding it, it's just the wheel spinning in air. At no load speed, torque is near zero and watts has also dropped to near zero. The max speed has something I don't understand to do with back EMF of the motor equaling the battery voltage. Something like that, I no doubt have it at least slighly wrong though.

 

[RTLSHIP]

Is the 9 continents model sensorless?
I have recently started running a small LYEN controller 6 FETS with the Aotema motor. Very good results so far with 36 & 48 v packs.
This controller is programed to run from 36 to 72v and can be reprogramed. Top speed is 23 mph w/36v and 28 or 29 mph
w/ 48v( no wind).

 

[easieSTrider]

Well I'm well over 500 miles now on the kit and the hub motor is running great. I thought I would be a little further along by now but I had to take time out to do a full roof replacement with new stringers, decking, all of it (man, what a chore. Dogman you are my new hero!) Anyway the only small setback I had was a controller failure that Terry at HTB quickly replaced under warranty. as a matter of fact HTB made sure our controllers passed in the mail for a very short downtime! For all of you contemplating buying somebody else's discount hub kits, be forwarned that dealing with anybody but reputable resellers (such as those that support E.S.) may be risky. I couldn't be happier with the sales & service from High Tech Bikes.

 

[rearengine]

Could any of you tell me if there is a geared motor with no hall sensors , like the aotema motor .. I have a aotema Bl in a 20" front wheel on my Rans recumbent.. I think I have about 400 miles on it , and have had no problems what so ever .. I would like to have a geared motor for my other bike for the lightness of it , and the simple wireing like the aotema.. I really don't know a lot about this stuff , so I hope you will bear with me .. Thank in advance for any info .. Bill

 

[OneWayTraffic]

As I understand it, it has to do with the way the tourqe curve of electric motors graphs. At zero rpm, the motor has it's maximum tourqe. As the motor gets going, you reach a peak in wattage, but tourqe is already going down. Next you reach no load speed, which is the fastest the motor can spin with no load on it. So nobody is riding it, it's just the wheel spinning in air. At no load speed, torque is near zero and watts has also dropped to near zero. The max speed has something I don't understand to do with back EMF of the motor equaling the battery voltage. Something like that, I no doubt have it at least slighly wrong though.

Back EMF is basically Newton's third law in the context of electromagnetism.

Magnets spinning near a conductor induce a current in that conductor. This current has to oppose the movement that created it, otherwise the magnets would speed up and up and you'd soon be going faster than an F-15. (http://en.wikipedia.org/wiki/Lenz%27s_Law) Another way to look at it is that some of the energy of the spinning magnets is drawn from the moving magnets by way of the interaction between the magnets and the wires.

A demonstration of this that you might see in a physics class is to place a round magnet in an aluminium tube (Anything except steel will do.) Tilt the tube and the magnet will take a very long time to slide down, as its movement is constantly inducing eddy currents in the tube acting as a brake (The energy to make those currents has to come from somewhere, and it comes from the movement of the magnet, slowing it down.)

http://www.youtube.com/watch?v=kU6NSh7hr7Q&feature=related