Kepler Bottom Bracket Friction Drive For Sale (Finally)

Kepler said:
A few minor adjustments needed...

Thanks for the tips. I pulled the motor up to just touch the tyre and that worked. I also added a spacer washer to the top locking screw - as this increased the screw's shaft diameter enough to stop the motor rising up so far it scraped on the bottom of the kickstand plate. Both the top and bottom locking screws are at the end of their travel arcs as this bike has a 120mm distance between the centre of the bottom bracket and the tyre surface (technically 10mm over your specified limit for the drive unit). Pic below.

Anyway, I've just been on my maiden voyage and it's pretty exhilarating :D I don't have a speedometer but I reckon I was getting up to 20mph on a flat surface without peddling. It sailed up the local gentle hills at full throttle. Noise-wise (in FOC mode), the motor very quietly whistles at low throttle and then the sound changes to a considerably louder and lower-toned electric vehicle whir when the motor bites up into the tyre - this was loud enough for people to look across as I passed them. I don't know if further tweaking will quieten it down - I hope so. On some throttle twists, something happens to cause a grinding noise (a bit like the mashing of gears in a car), and I'd like to resolve that. The Vesc (contained in the Lithuanian alu box) got hot but not too hot to touch.

It's a great bit of kit and good fun to ride. I did about a mile on it and would have stayed out longer but I went over a bump and my saddlebag containing the battery flew off and was left dangling on a wire by the back wheel :( ...pit-stop time.
 

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Great to see you have the drive up and running. The geometry you have needed to set to get the drive to function certainly is at its limits however looking at your picture, it does look acceptable. I will cut a few longer swing arms for people who run into the same reach issue as you have. Let me know if you need one.

So noise wise I think you need to go over you FOC settings again as it should be quiet enough to be only heard as background noise and certainly not loud enough for people to significantly notice the bike.

I also noticed that your C clip on the motor shaft is very close to touching the pivot arm. make sure it is not scraping. Under load, it might be flexing just enough to touch and when it does, the noise is surprisingly loud.

With regards to setting up FOC, here are a few tips to make sure you have had detected the optimum settings.

1> Load default setting and take a screen shot of the FOC page taking particular note of the items the red boxes. These should change when settings are applied
2>Measure R & L and make sure the motor reacts during the measure.
3> Do a disconnect and reconnect
4> Measure Lambda however change amps from 6A to 10A (green box). Again make sure the motor reacts this time by spinning up.
5> Do a disconnect and reconnect
6> Hit the calc CC button and observe if changes are made
7> Do a disconnect and reconnect
8>hit the first apply button followed by the second apply button below. You should see the settings that I highlighted in the red boxes change to your new settings. You can compare them with your screen shot just to make sure they have changed.

This procedure works for me and gives me the most consistent results setting up FOC.

Let me know how you go.
 

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Hi Kepler
Could you please add me to your list of excited customers ?
Is there still no BB30 options on the FD setup as of yet. It would save a crankset switch.
I'd love to try this over here in Scotland on some big climbs
Kind Regards
David
 
Please advise if you had any of the longer swing arms cut. Chain stays on my 1983 Trek 720 are extremely long and a revised swing are might provide more adjustment options since it looks like I'll be cobbling some kind of a "kickstand" mount. Thanks.
 
Thanks for the BLDC info Kelper. I followed the instructions and below is the screenshot after doing so - not identical to yours but it looks pretty close to me. I changed the Lambda to 10A, but couldn't work out how to "spin up" for this entry - I so just clicked on "Write configuration" and did a disconnect/reconnect after that. This entry didn't change when I clicked "Read configuration" so I guess it went through (?). Here's a pic of my bike as it currently stands... took an age to build a sturdy rack for the saddlebag, but I think it'll hold firm :)



 
Haha - thanks Kelper. The stealthiness of your design is why I opted for it. I've also stripped all the original front and back derailleur gear stuff off the bike and replaced it with a Sturmey Archer 5 speed IGH - adding to the understatement, I think :)

BTW - I had some BB shell slippage issues with the unit (as discussed further back). I've resolved this by bolting a small right-angled bracket to the bottom of my kickstand plate and then replacing the M4 locking screw in the unit's top adjustment slot with a longer one that runs all the way through and bolts to this bracket. Hopefully the whole thing is fixed in position now...

 
That's a good solution to stopping the bracket slipping under load. I have always used cup style screw in bottom bracket bears which give you plenty of surface area to tight against. It can also be advantageous to assemble it with some medium strength locktite.

I am thinking of adding a generic brace similar to what you have done as part of the overall design.
 
Awesome stuff. I've lurked for quite a while. Fantastic bit of kit - nice and lightweight. I commute 200km a week on a Giant Defy and this looks perfect for a bit of a helping hand sometimes.

Figuring out how to mount this on my BB86. Your 2015 Trek conversion looks to be the answer.....

I'll send a PM to get on the list.
 
Hi all,


Just to let you all know I wont be producing any more drives this year.

My apologies to those who have been waiting patiently for new drives to come back in stock. Unfortunately my daytime job work load and family commitments have made it impossible to spend time on further production.

However, I will look at doing another small run in mid January.
 
Hello, I would also like one from your next production run.

Thanks for all your effort and inspiration...
 
Hi Kepler
I would like to known if you Can send me your complete fiction drive with battery and etc... assembled (ready to use)
I can't do It absolutely !!!! :(
If It is possible, Can you tell me please?
I Hope in your answer
Excuse for my english
Thanks very very much
 
Hi Kepler,
I too, would like a drive mounting setup. I have made a setup that mounts on the Seat tube and it worked great. I used a 1500 Watt motor, but only use 1/2 to 2/3's of the power. I use a maintained push button and the speed pot to set my speed. I don't really need to go full bore, because it drives the amps up exponentially. I can make it to work and back (~25 miles) on 6s4p Liion 18650 pack. I still work hard at peddling, so I still get a good workout. Love it.
So, one of my bikes will have your setup and my other two bikes (one recumbent) will have Edrives, too. What fun.
Let me know when your brackets are available.
Thanks Tim
 
I am also super keen to get my hands on one! Even second hand! I am in Perth, Australia
 
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