hightekbikes.com motor kit review. Electric bike kit.

[stringbustr]

Hey everyone im new to this site, Im also new to electric bikes.
I just bought a Aotema kit from Terry at hightechbikes, and im going to call him but sense
I just joined this site I thought I would ask here fist.
You were talking about vibration at very low speed, sometimes saying that just a few inches
was enough to stop the growling sound.
Well on my Aotema I have to get-up to around 4 mph before it well stop the growling.
Im using a Lifpo4 36volt 10 amp battery.
Just would like to know if thats normal for this motor.

Thanks for any feedback.

 

[The Mighty Volt]

Hey everyone im new to this site, Im also new to electric bikes.
I just bought a Aotema kit from Terry at hightechbikes, and im going to call him but sense
I just joined this site I thought I would ask here fist.
You were talking about vibration at very low speed, sometimes saying that just a few inches
was enough to stop the growling sound.
Well on my Aotema I have to get-up to around 4 mph before it well stop the growling.
Im using a Lifpo4 36volt 10 amp battery.
Just would like to know if thats normal for this motor.

Thanks for any feedback.

I have the same kit and the same "problem".

At medium to high speeds, everything is butter smooth and very very satisfactory.

However, at low speeds or high load, it is ropey.....and I think it has to do with how well the hub sits into the dropouts.

You and I may have some filing to do.

That said, I love it. So few wires to deal with, and it really likes to motor if you give it some road to run into.

It wouldn't pull the skin off a rice pudding, but any hint of open road, and it just builds and builds. A real "straight stretch" warrior.

 

[The Mighty Volt]

HTB has a great deal on this kit now for ES members. See the for sale section for the link to get the discount.

Still a great kit, with better top speed than most others. Close to 30mph if you run 48v. No halls to fail, and less wiring makes a nice clean looking bike.

Ah yes, that reminds me.....I stuck a 48v lifepo4 on it and I noticed an immediate increase in speed and performance on straight runs.

However, I also noticed all 3 LED's come on on the throttle, and I noticed the controller getting warm.

Alarmingly, after what felt like only 10 minutes ragging the motor, my WATTS UP was telling me I had drawn over 2.0 Ah.....and I only burned up 1 hill.

 

[RTLSHIP]

Mighty volt, I fried my stock controller 2 or 3 times w/ 48v lifepo4. You are, in my opinion, taking chances.
The yellow empty light, should fade out after a while. Regardless, that's insignificant.

As to Stringbusters comments, it's normal to get a grunting noise when drawing more current. Grunting does no harm to motor. It should only happen during hard acceleration or when drawing alot of amps.

 

[The Mighty Volt]

Mighty volt, I fried my stock controller 2 or 3 times w/ 48v lifepo4. You are, in my opinion, taking chances.
The yellow empty light, should fade out after a while. Regardless, that's insignificant.

As to Stringbusters comments, it's normal to get a grunting noise when drawing more current. Grunting does no harm to motor. It should only happen during hard acceleration or when drawing alot of amps.

This "grunting", would this be characterized by a lot of vibes coming up the suspension forks and into the handlebars, fading rapidly as the bike gains speed?

Thanks.

 

[RTLSHIP]

It's a vibrating noise that comes from hub motor. I don't have suspnesion forks. On my bike, there isn't noticeable vibration on forks or hundle bars.

 

[dogman dan]

The grunting is the sound of the motor having a bit too many watts going into it relative to the speed of the rotation. Even sensorless hubs can and do grunt, but tend to less than sensorless motors. I have found that if it grunts loudly, you are likely to have just as good acceleration using less throttle, and then go full at a bit higher speed, say 10 mph or so. When the motor is grunting real loud, it's likely that the extra power is just making heat instead of motion. Loud grunting is harmless , but if the motor is too hot it could heat it more. I just back off throttle some, and downshift if it starts to grunt loudly on a steep hill. A few grunts leaving the stop sign is no big deal.

Wasn't there a nicked wire on your motor when you were blowing controllers RTL? or was that someone else?

As for the controller getting hot, well yeah, overvolt it and then ride full throttle up hills and things could cook. Too bad there is no 72v 40 amp version of this controller that I know of. I got a 5304 with fried halls that would love one.

 

[The Mighty Volt]

My only beef with the kit from HighTekBikes is that it is ropey from the go. That is about it.

Cycling hard in 18th gear and kicking in some throttle makes for effortless fun.

I cannot wait to couple it with a hardcore motor on the back.

 

[Kevin]

I have a HTB kit with a 36v 20 amp battery. Everything was fine until the battery charger connector shorted and caught on fire! Has anyone else had problems with their battery charger connector, either on a HTB kit or other kit?

 

[dogman dan]

Who hasn't had a problem with a charger connector? I don't know what Terry is using since I didn't get his battery. I used to use molexes and had to replace em about 4 times a year. Now I use andersons and have better results. The main problem is the skinny wire used in the charger iteslf. With just a few strands, it would break where it flexed at the crimp to the connector.

 

[RTLSHIP]

I accidently dropped my backpack (last summer) with 48v charger inside. Next time I used charger, all I got was smoke. These things are fragile.
Also, the wiring around connectors are subjected to bending, pulling etc. This can lead to a contact (charging) problem.
My charger was not f/ Terry, however.

 

[HighTekBikes]

There is a problem with the type of DC connectors used on our packs as well as Pings and most other packs without hard cases. If you try real hard, you can short the internal pin of the female connector (on the pack) to it's outer part. If you take the male plug on the charger and hold it sideways so the barrel is across the female, it can short. Now what happens when you put 30+ amps at 36V across a thin piece of metal? Yeah, it gets red hot and melts. I guess it's too much to ask to have the user plug it in straight. We have been looking for an alternative connector but no easy solution. I did find a larger version of the female side where the pin is recessed somewhat. We are sending out adaptors to our customers by request. Future packs will have this as an interim solution. PLUG IT IN STRAIGHT !

 

[dogman dan]

In case there was a misunderstanding, the charger connectors I had problems with were installed by me, and any problems were entirely my fault, with the exception of the ones that used to come with a Wilderness Energy kit. Those speaker wire plugs really sucked.

The real doozy was the bright idea to use lampcord, and color code the end so I wouldn't plug it into the wall. Of course, eventually I did, POOF.

After that I used a lot of cheap molexes, and had problems with the wire bending till they broke off. Now I'm using andersons, put together so I can't possibly connect the charger to the battery using the wrong wire. The andersons don't allow the wire to flex at the point where the conncector crimp starts and seem to last forever.

My latest chargers have the same kind of pin connectors on the dc side Terry is describing, I think. Ping chargers. I would think it would be pretty hard to screw one up, but I guess it's possible. On my 36v one I cut off the connector and put on a set of andersons since my 36v battery is already set up for those.

Carrying around a charger, I've had the wiring break off the board inside where it's soldered a few times. Sometimes the charger doesn't work, and looking you find the problem. Sometimes the problem announces itself when the loose wire shorts, and then the charger really doesn't work.

 

[Kevin]

"We are sending out adaptors to our customers by request. "

The adaptors are a really good idea. That way, when the pig tail adaptor shorts out and is ruined, the customer can just return the adaptor, and charger if needed, and won't have to return the entire 20 lb. battery. A much better solution than insulting and berating the customer to PLUG IT IN STRAIGHT!!

 

[HighTekBikes]

Hopefully with the new connectors it will be impossible to short them out. We are working on a new battery pack that will have an aluminum case and slide in rack like some other companies are selling. When that product is released we will stop selling the bare packs to consumers and only offer them to OEM integrators. The bare packs are not idiot proof and while most of the folks who visit this forum would have some knowledge and be able to use the packs safely, they probably are not suited to the average consumer. It's difficult to compete with China sellers like Ping on the bare packs. No one is going to be shipping a pack back to China after damaging it, calling them on the phone, or making any demands. They are lucky to get a return email. With the customer support required, it's not worth it.

 

[HighTekBikes]

We are definitely going to change the charger connector. Still deciding one which one, leaning towards a trailer hitch type. We also might include an inline diode which would completely eliminate any possibility of a short. The charger would have to be tweaked up a bit to compensate for the diode. If you didn't, it would only be .04v per cell low on a 36v pack.

 

[easieSTrider]

Hi all, newbie here on this great ES forum. I'm putting a little feedback on the Hightechbikes kit.
I got over 100 miles now on my Aotema hub motor from HT bikes and I love it! I find myself riding further & longer than I ever expected. I have it mounted on a Trek 7300 and get about 23-1/2 mph on it, 26mph pedddling. I am looking forward to commuting to work as soon as the frost lifts in the mornings. I had to reinforce the seat post clamp mounted rack to help support the battery pack over these rough & treacherous NY roads. Everything has held up so far with zero problems with motor, controller, battery pack and charger. This hub motor and battery pack are a nice setup for a reasonable price, and Terry helped out with all my pain in the arse questions. Also I want to thank all the regulars on here that contribute excellant information about e-bikes.
One question I do have is there anyway to monitor amp draw without a CA or Wattsup meter?

 

[RTLSHIP]

You can time how long it takes to recharge pack. I have a 36v 2 amp smart charger
Work is 4.3 miles. It takes about 1.5 to 1.75 hrs to recharge That's about 3 amps assuming the charger is consistent. The only other way is probably to buy a cycle analyst, watts up meter or like device. This motor is energy efficient.

 

[easieSTrider]

I was wondering how to check that because I do not see much voltage drop when I check it after riding.
So basically if I can go 5 miles with about 3 amps (1-1/2 hr time on 2a charger), I should be able to go 20 miles using 12amps or 80% of my 36v 15ah LiFePo4 battery pack without any damage to it? I was hoping for a more technical way to measure it with multimeter.
Someday I would like to get a Wattsup to to keep an eye on usage.

 

[RTLSHIP]

I think I'm just over 3 amps for 4.3 miles and pedal helpfully when accelerating. With lifepo4 you probably will not see a major voltage drop until the near end. This makes a multimeter nearly useless. Assuming you have a healthy pack and don't weigh alot, I think about 1.3 miles per amp is a good estimate.
My Bd36 brushed motor was getting about 1 amp per mile. Not that bad either.

 

[dogman dan]

I started out just timing charges, and made some calculations, and when I got a killawatt to actually measure watts on the ac side of the charger, It came out pretty close.

I really like using the 1 ah =1 mile rule of thumb for 36v, when riding full throttle with this motor. So you can count on 15 miles of full blast riding and still have a nice reserve left most days. And count on making it all the way on the worse ones.

I would say your maximum possilbe range would be in the area of 30 miles, by riding less than 15 mph.

 

[easieSTrider]

Thanks Dogman, that's good to hear. I am peddling most of the time on WOT or hypermiling as I believe you call it, so I am eager to see what the ultimate distance will be. I do not have any monster size hills that I need to billygoat over, but nice mid-length to long elevation changes, but I'm hoping for at least 28-30 miles on Lifepo4 36v15ah.
How do you calculate the efficiency of this motor? Also, one thing I have noticed is that under load (torque) the spokes twang like a guiter string. I'm wondering if this is normal or do I need to re-tune the rim?
I am pleased with the Aotema motor as my first electric hub purchase.
BTW - I gotta say these electric bikes are like drugs for us old guys, I just can't get enough.

 

[dogman dan]

I was getting just about 22 miles out of my 36v 20 ah WOT at 24 mph, but with light pedaling, not adding more than about 1/2 mph. So 17 miles would be my guess at WOT. My personal best on that battery was 39 miles, with quite a bit of the travel at 12 mph. To get 30 miles you will have to travel at about 15 mph or less.

I just got my cycleanalyst, but haven't ridden more than around the block. Facinating to see the watts leap with any kind of acceleration, and then drop amazingly when you pedal hard once at top speed.

 

[easieSTrider]

Keeping with the theme of this board, I will hypermile this motor to see what the end mileage results are and report back.
Where might I find the technical dimensions (spoke hole pattern) of this hub so that I can better match a 700c rim?
Most of my questions are of technical nature so maybe I should address them on the technical discussion board.

 

[dogman dan]

Ask Terry, at HTB what spoke length is on a 700 c. I think it's the same as clyte 400 series though.