Kepler Friction drive comes of age.

That is brilliant. Great work mhaskell.

I reckon you could get away with just one pack most of the time. So where did you end up mounting the Vesc? It would be nice to incorporate the Vesc into that battery mount. Also what voltage are you using?

What setting was causing the drive to disengage at high speed?
 
Kepler said:
That is brilliant. Great work mhaskell.

I reckon you could get away with just one pack most of the time. So where did you end up mounting the Vesc? It would be nice to incorporate the Vesc into that battery mount. Also what voltage are you using?

What setting was causing the drive to disengage at high speed?

I am running the packs in series, for 36v nominal. I am printing an enclosure for the vesc-x , mounted under the bottom bracket. Fitment is difficult since it is an areo frame with high aspect ratios.

The drive disengagment was a mechanical issue actually. I needed to rotate the bottom bracket mount clockwise to move the arm bracket closer to the tire. I needed more bite to force the motor up the tire.

I am using the largest bracket in the kit, but another 5-7mm longer would be ideal.
 
I have been enjoying the posts so far. I too got one of the prototypes. I finally mounted it to my bike and have tested with my controller and servo tester. runs great and really gets the wheel up to speed. I have been busy with work and home projects but hope to have set up and try a ride in the next few weeks. I too am having trouble with the engagement and had to adjust closer to tire. so for my test I put it on the tire. if I cant get it fine tuned I will probably go to the cable adjust method. You might want to consider that in your marketing Kepler as many of us do not have the talents you and others on the forum have.
I will definitely keep following. next I want to try the button throttle but for now I am happy that I was able to modify the bracket to fit my motor and get the wheel to spin :D
 
Finally got the new road bike rolling today. I wanted this bike to be even lighter then my last road bike so the only way this was going to happen was to stick with a 50mm motor rather then a 63mm and use a smaller battery pack. Tried two 50mm motors, A Keda 230kv motor and an even smaller Turnigy SK3 5055 280 kv motor. With an ebike controller, the Turnigy motor struggled and was quite loud. However, with the Vesc in FOC mode, what a difference.

The little SK3 has transformed into a really sweet motor. Using the Vesc in FOC easily halved the noise that I have experienced with any other motor using a stock ebike controller. It is not going to break any power records, but its adequate for what I want to do.

In total I have pulled 700 grams off the bike. Doesn't sound like much but on a bike like this, its close to 10% of the total bike's weight. I am now running a 7S2P pack using 3500mah 18650 cells so this knocks off 400 grams and the motor is only 370 grams so this takes another 150 grams off the total weight. Other 150 grams comes from the lighter speed controller. Also got the 2 button throttle going nicely which gives me either 50% current or 100% current. Running the reduced current more then makes up for the reduction in battery capacity.

So the Vesc is a real winner. I was sceptical about what difference running FOC on a sensorless RC motor would make. And when bench testing, the motor was noisier in FOC mode then BCLD mode. However, under load, the motor is significantly quieter. I would say at least 50% quieter. Other wins are that the motor is definitely smoother and can take off from really slow speeds, in fact I think it would take off from a dead stop if I wanted.

For the sake of an extra $60 or $70, I would recommend the Vesc over and ebike controller any day. It is in my opinion, the prefect match for this friction drive.

I will post up some video with sound tomorrow to demonstrate the difference in noise.
 

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awesome. selfish me is happy that you've completed this and will soon be making a kickstand mount version ;) my 21pound folding bike is waiting for you!
 
Managed to get out and do some testing using of the new bike conversion with the Vesc controller in FOC mode. Got some issues with the speed controller cutting out intermittently but noise wise, I am very please with the results.

You be the judge.

[youtube]6F8xD2zRV_0[/youtube]
 
Wow, this is wonderful. Vesc for the win, I guess :)

What kv is your 5065 motor?

200 kV. Good to run at 9s or 10s. It is quite long so I don't think it will fit on a standard bike and clear the left crank. The short can 63mm I think would be quiet also. Will test these next week
 
It's a bike assist system so pedaling is part of the deal. :) The assist is subtle but effective. Basically it gives you an extra 10kph above what you would normally ride at without assist. However It will maintain about 30kph on flat road with out pedaling just like any. other 250W drive.

Riding with the drive activated, it basically takes me to pro rider abilities. Yes I can ride OK and ride typically 200km every weekend on my unassiated road bike. With the sound before, it was pretty obvious something was going on. I recon now I am under the radar. This bike is mainly a commuter. Got a 50km round trip for the commute and do this every day if it's not raining. I am the fastest bike out their on the bike paths. Yes, it's not a free ride buts it's an easy ride. If you want to be a passenger. Forget this drive and get a big heavy hub motor. Horses for courses.
 
Yes I already have a big heavy hub motor.

The good thing would be to be a passenger at 250-500w power at high efficiency.

Even at 250w, it should be enough to cruise at 25km/h, which is itself is not bad for a 1.7kg kit?

It'd probably have some buyer too?
 
Nice. You'd prolly squeeze out a few more Km/h if you changed those flip flops to panda bear flippers.

Home-font-b-Slippers-b-font-Men-Women-Lover-Animals-font-b-Panda-b-font-Autumn.jpg


Get the biggest front chainring you can fit and up the VESC's capabilities using 10s? :p
 
Kepler said:
a 10K pot over the 3.3V and GND with the wiper to the ADC_EXT pin? Starting to get my head around this controller i think.
yup. its that easy.
 
I had some SPD Sandals many years ago when I lived in a warm/hot part of California.

The Shimano's will be better Quality.

https://www.amazon.com/Shimano-SH-SD66-SPD-Cycling-Sandals/dp/B002MGBIO2/ref=pd_sim_309_1?_encoding=UTF8&pd_rd_i=B002MGBIO2&pd_rd_r=XQP43JRHGGQWC53PPM7F&pd_rd_w=eMp3L&pd_rd_wg=ECHVf&refRID=XQP43JRHGGQWC53PPM7F

https://www.amazon.com/Nashbar-Ragster-II-Cycling-Sandals/dp/B004UMDST4

When using SPD Sandals and Pedals, be sure to loosen the spring tension on the Pedals , to be able to get out of the Pedals , because with Sandals you do not get as much side movement leverage.


Kepler said:
Flip Flops are the universal footwear for Aust. Thinking about getting cleats fitted to a pair :lol:
 
Ok, the Vesc is now fully sorted. Figured out what the cut out issue was. You can't treat this controller like an ebike controller as there are subtle differences that will catch you out if you do.

Also have finalized the drive design and will be placing an order for the first production batch with my laser cutters on Monday. Been a long time coming and i thank all who have been patiently waiting for the drive to be available.

I will be creating a sales thread over the next day or 2 and will be in contact via Pm with all who have expressed interest in purchasing the mechanics set.

I will also be putting together 2 drive configurations for people to use to select all required items to put together an operating drive. One config will be an economy combination of parts that gives you a good operational drive for the lowest price and the other configuration will be the combination that gave me the best overall results. I will also be including an assembly manual including all my Vesc settings and information on how how to build button throttles with voltage dividers to suit both types of controllers.
 

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Hi Kepler,

how much do you think will be the mechanical motor mount part only?

Best wishes, Payder
 
Sorry, I didnt express myself very well there... :)
I wanted to know the price for your mechanical assembly without motor or anything else. Basically only the machined parts you designed.
 
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