In the News

By: Ampedbikes  05-Apr-2012
Keywords: Bike, Electric Bike, Hybrid Bike

Personal reviews and "thank you's" at the bottom of the page.


Autonomous Bike?

just wanted to share with you one of the bikes we finished that has a donated Amped Bikes kit on it: 

I spent most of Christmas Eve this year testing the complete rigid rider setup on the instrumented bike and it seems to be working, hallelujah!

The complete rigid rider instrumented bicycle.


The bicycle is equipped with a multitude of sensors:

  • Steering characteristics: Steer angle with a potentiometer, angular rate about the steer axis, and steer torque
  • Wheel speed with a dc generator
  • Pull force: We can attach a rope to any point on the bicycle and pull for input disturbances and measure the force with a load cell (a custom built amplifier built by Cal Stone in the late 80's amplifies the strain gage signals)

The on-board data aquisition is made up of:

  • Asus EEEPc net book
  • National Instruments NI USB-6218
  • Matlab and customized DAQ software to take data from the VN-100 and NI USB-6218

We are using an

rear hub motor, 7lb 36v lithium ion battery, and their speed controller so that the rider's pedaling doesn't become a confounding factor in the data analysis. The human is restrained from movement with a body cast which is attached to the bicycle frame, magnetic knee restraints and clipless foot pegs.

The good and the bad

Most of the design and construction went fairly smooth (mainly because I helped build a similarly instrumented at TU Delft) but there were some hiccups along the way. Here is some details about what did and didn't work:

Steer Torque

The steer torque measurement design seems to be giving very good signals that are not at all affected by non-torque moments and forces applied to the handle bars and front fork. The zero-backlash telescoping double universal joint from Sterling Instruments does the trick. I also have a "slip" clutch from Sterling Instruments that protects the steer torque sensor and universal joint from being damaged. The clutch is advertised as a slip clutch but it is more akin a break away clutch. When you think of columb friction with a static and sliding coefficient of friction, those aren't usually largely different, especially for metal objects. So if we ever do hit the torque limit (20-23 Nm) we will potentially lose control of the bike. I will test this out though and see if the low slipping torques will be enough to guide the bicycle to safety. The second issue with the slip clutch was that I ordered a custom set clutch for 150 in-lbs +/- 10% but when I tested the clutch after getting it (8 week lead time), the clutch broke away around 260 in-lbs. Turns out that their slip clutch specs are for 18000 rpm which is not stated anywhere in their catalogs. After sending the device back and finally getting to talk to someone about the issue I got I new clutch that breaks away around 180 in-lb for low speeds (of course I had to pay the shipping to get it there and back). The new slip clutch has a little backlash too, so I have to figure out how to take it out. If I do this again, I think I'd make my own slip clutch.

Data aquistion

We decided to buy the VectorNav VN-100 IMU to share for each of our bikes and it outputs two types of serial protocols SPI (through the 20 pin header) and RS-232 (through a D-Sub connector, the header or USB). I intended to plug both the VN-100 and the NI USB-6218 in through two usb ports on the EEEPC and sample them simultaneously. But if you want simultaneous sampling, that doesn't work. When we purchased both devices I was under the impression that I could sample the VN-100 with the NI USB-6218 but that turned out to not be so true. I ended up syncing the data after the fact by sampling an identical event with both the VN-100 and the USB-6218. You can read about that on the

. If I were to do it again I would buy a DAQ card that can that can sample both SPI and analog data (open source solutions exist: Python and something like LabJack or Arduino).


I used Matlab's DAQ toolbox to communicate with the USB-6218 and the Serial Toolbox to communicate with the VectorNav. Then I wrote a

to collect data smartly. You can enter in all the info about the run and the data collection is triggered by a button on the handlebar.

Screenshot of the program used to collect data.

Personal Reviews:

 Am wondering about the feasibility/wisdom of carrying my battery in a handlebar-type basket instead of on the rear wheel rack. 
It seems like this would even out the total weight load on my tires. (I have a front wheel motor) Any comments one way or the other? 
By the way, I now have almost 4000 miles on my ampbike, and continue to be amazed at how well your product is performing for me.

Recieved my front wheel kit with the tube battery today. It took me about an hour and a half to install. The video on your site was a lot of help. Attached are some pic of my install om my Day 6 bike. My wife and I went on a short ride and your kit performed very well. Kay has a Bionx system and I would say that Amped Bike performed as well or better than the Bionx kit and at about half the price.
Thanks a lot,

thank you for the help,Danny Ray, The advice worked great, and you product is truely a fine piece of craftsmanship.its been two weeks of daily commuting, and no problems:) unlike like that 80cc, fix every day, nightmare.jayme Chamberlain, satisfied customer.

The 20" wheel is working perfectly on my trike! I'm riding to work every day.
Thanks a bunch,

Its been a while but I just wanted to let you know how much I appreciate you working with me to get my kit up and running. Turns out the culprit was the battery from Mr. Ping. It was frying the controller and then the kit wouldn't work. Once I got your battery and a new controller everything worked fine and I absolutely love it. Thanks again for working with me. I am a completely satisfied customer.

Just ordered a second conversion kit for my wife's bike. I have been using mine regularly and love it. Thanks for a great product.

Dear Lysa,

Students and I just wanted to thank you for your support on the hybride bike projects. Attached is the picture of the college students, Travis and Ricardo, who had successfully mounted your motorized wheels in their bikes. They love your products.
MAE Department
San Jose State University
San Jose, CA 95192

Thanks for taking care of me. The bike goes really good!!! I'm a happy customer!!!!
It's fast ,but not too fast. Perfect for going up hills.

Thanks again,

I recently install your rear direct drive kit. I am very happy with your product. I rode it to work today for the first time. Fantastic. Thank you.

I received my kit yesterday around 7:30 pm. Spent some time last night looking it over and familiarizing myself with it. Got up early this morning and spent most of a very enjoyable day thinking about the cleanest way to install, routing, changing out brake levers and such. Took it for a test ride of about an hour and all I can say is WOW!!!

I will take some nice close up pics of my install and e-mail them to you. You are welcome to use them as you see fit. I have talked to a few local bike shop owners about AmpedBike and I expect you will be hearing from them about your product.

Thanks again,

hiya, 1000 miles on amped bike..awesome!!!!..and i don't hyperbole..seriously, great equipment and never underestimate the importance of cruise control.i live in the rural and can go 20 minutes at a time w/o touching the throttle..this thing is the greatest, thanks for everything, brian

Thank you very much for the donated Direct drive 700 cc motor. Apologies for the lapse of time to install such motor, as I needed time to budget for batteries and charger. Emailed Lysa, about such concerns but had no response. This product has totally changed my families live style, dignity and budget. My bicycling range, including trailer, has now increased ten-fold, saving my family $200-$300 a month. We can now access discount shopping while saving on transportation.
As mentioned before I am disabled, not driving, 260 lbs, 52 years old, and regularly, between saddle bags and said trailer can bring 200 lbs of groceries home over various terrain for a family of four. Your product is everything as advertized plus much, much more. Many pictures, many stories, including the durability of your product, including the embarrassment of my 16 year old son spreading my bike and your product over two properties after the crash. All is well, wish to share said pictures and stories personally to you, to be used at your discretion. Your product has been bashed, crashed, hauled 500 lbs +, including bike, rider and trailer, over some extreme terrain and the Campbell family loves it.
Dignity always

To Those who made It Work!
I stumbled onto your website last fall while researching electric bikes. My sons and I try to get together once a year for a Wv trout fishing tip on the Cranberry River. I'm 61 and only ride a bike for this event. Surgery would have not allowed me to fish with them. I purchased your front wheel kit, installed it using your instuctions and it made the maiden trip last week. What a really good product!! Its 5 miles in with 5% overall rise with ups and downs . I helped a little with the rear wheel going in, and let the power wheel do it's job all the way out.It Worked.Thanks for a Great Product. Bob

recieved my kits on Nov. 24th on time. took about 1 1/2hrs to put together put on charge after short charge checked out if it worked it did adjusted brakes put back on charge wait for next day for long test ride but rained all day had to work on thanksgiving day no busses running had to ride bike to work 23 miles away. made it to work in less than an hour put bike on charge worked 8 hrs rode home. the kit is everything it is said to be real happy with product. what a test ride!!!! did not pedal at all. It is perfect for Southwest Florida , flat ground. once again like to say I'm very happy Thank You .
My AmpedBikes electric hybrid bike kit. 500W 36V stock kit on a ~'90's GT AllTerra mountain bike.
Being low tech and low budget, here's the specs on this rig:
-21-speed GT AllTerra Timberline hardtail
- front wheel 500W 36V 26" stock motor, wheel, spokes, and tire.
- Half-Grip twist throttle
- original cargo rack from the kit.
- heavy canvas saddle bags restitched as pannier bike bags and coated with fiber glass epoxy resin to re-enforce the canvas.
- six recycled SLA UPS backup power 7ah batteries @ 6lbs each. Packs are arranged in two 3-battery 36V packs in order to split the amperage and not tax the poor old SLA's
This setup gets me to and from work across the Cuyahoga Valley National Park from Akron to Fairlawn on a single charge. ~20 miles roundtrip. Up some nasty hills both directions!! Pretty good for recycled batteries that were put out for trash.
I run a de-sulfator battery cycle on each battery individually every couple months.
Been running this bike since May 2008 on the same batteries.
All in all spent ~$400 total on kit, bag, and maintenance on the bike last year. Well worth it!!AmpedBikes is the place to get your own do it yourself kit!

The information in this article was current at 27 Mar 2012

Keywords: Bike, Bike Conversion Kits, Electric Bike, Green Transportation, Hybrid Bike,