Friction drive outrunner setup. New DJ bike.

[EVTodd]

What's a desktop CNC mill? Is it like this:



Cuz, I just picked me up one. No, CNC here baby!

How are you coming on your drives Todd? Are you still planning on producing a couple?

Nice Rusnok mill. You need to convert it to cnc!

The one in my photo is a highly modified MaxNC 15. Just like friction drive a lot of people talk crap about MaxNC but I've had great luck with them. I'm a firm believer that if you're making small parts a small machine (set up correctly) is fine. I currently have 2 small cnc mills, a larger Chinese mill, 2 cnc lathes, and a manual Chinese lathe. Fun stuff!

As for making a couple of drives... I have 3 sitting in front of me right now. One is my girlfriend's and I'm going to make one little change to the other two. Not quite sure what I'm doing with them yet. lol

[EVTodd]

Sneak peek of my girlfriend's Kona:



This is one burly little mount. No flex at all. I think I like it a lot better than the seat post racks I've been using.

I wasn't going to upload any pictures until the mount was all polished up. Oh well.

I'll start another thread for this bike soon.

[mani9876]

wow this looks amazing! is it milled out of a big aluminium block?

atb
manuel

[EVTodd]

wow this looks amazing! is it milled out of a big aluminium block?

atb
manuel

Thanks! It's actually just a couple of plates of aluminum, one block, and a piece of square steel tubing. Pretty simple.

[spinningmagnets]

Another great design! Well-thought out Todd.

[EVTodd]

I finally got my keychain video camera. I still need to figure out the best Kino (Linux video editing software) export settings for Youtube. The raw video actually looked pretty good until I uploaded it.

Here's the first little video I shot on a bumpy loose gravel trail I ride almost every day. I'm going to try to get the quality improved a bit and get some video of the drive's sliding action.

Oh! Remember kids... You can't use friction drive on gravel!



Looks like I need to get a faster sd card since I'm getting some flickering of the date/time stamp.

[spinningmagnets]

Wow! looks good...have you been able to measure amp-draw, Todd? I'm certain its good, but I'm very curious about the actual numbers...

[EVTodd]

Wow! looks good...have you been able to measure amp-draw, Todd? I'm certain its good, but I'm very curious about the actual numbers...

Not yet but I will soon. I'm waiting for my bullet connectors to show up so I can get the Turnigy meter going. Of course I ordered them from China so it's taking forever.

[drifter]

I'm impressed, excellent work. What happened to your past photos, they have gone missing from flicker.

[EVTodd]

I'm impressed, excellent work. What happened to your past photos, they have gone missing from flicker.

Thanks! I usually don't ride those trails that fast since it's REALLY loose gravel and my bike tends to have a very light front end at speed.

As for the photos, I didn't even realize they were gone until just recently when someone told me. Something got screwed up with my Flickr account. I'm going to post a thread with just pictures and videos of my builds so it's all in one place. The old threads were getting pretty cluttered with other stuff anyway.

And I took my other Youtube video down myself because of some very rude comments (on Youtube not here). I'll repost that video again too, this time without leaving comments open.

[AussieJester]

GET OF OFF THE GRAVEL friction drives dont work on it mate sheesh get with the program

Excellent video mate well done, shows the friction drive is a lil more versatile than some think

KiM

[EVTodd]

GET OF OFF THE GRAVEL friction drives dont work on it mate sheesh get with the program

Excellent video mate well done, shows the friction drive is a lil more versatile than some think

KiM

Lol. Thanks. Now I just need to get the video quality up a bit. I've tried uploading it in several different formats and it still looks the same.

[etard]

Todd, that video doesn't seem so bad, my GoPro isn't much better. I don't have the HD one though. I gotta get me one or two of those, what $14?

[EVTodd]

Todd, that video doesn't seem so bad, my GoPro isn't much better. I don't have the HD one though. I gotta get me one or two of those, what $14?

It just bothers me that it looks so much better before you export it. I know Youtube's quality sucks but there has to be a setting that looks closer to the original.

But yeah, these little cameras are a lot of fun. I had purchased one of the Insignia flip cams from Best Buy a few months ago. It was $75. At that price I was disappointed and took it back. The keychain cam was $7.80 (that's with shipping included). At that price the quality is great!

[EVTodd]

Wow! looks good...have you been able to measure amp-draw, Todd? I'm certain its good, but I'm very curious about the actual numbers...

Ok, I just got the bullet connectors today. I got everything buttoned up and went for a quick ride just to see some numbers. I only rode about 2 miles but a mile of that was up the hill I ride almost every day.

My top speed was 24.5 mph and max amp draw was 52 amps. That doesn't seem too bad for an uphill run, does it?

Now I'm really curious to see the numbers for my gf's bike. I'm guessing it's going to be pretty low if I only pulled around 50 amps. Of course things may change a bit on a real ride. We'll see.

[spinningmagnets]

I was greatly encouraged when you reported you accidentally used the 60A controller (which survived), as it was sitting next to the 80A controller you intended to use. Since Kepler is using the motor-shell as the roller, his 2-1/2" diameters would of course cause a higher amp-draw than the 1.0" roller you are using. Kepler reported that he was doing OK with an 85A ESC, but in order to have a safety margin, he recommended the Castle Creations 110A unit to his customers.

This led me to choose the Turnigy 6S/85A unit which was only $37. Since it can take two weeks+ to get parts from China, I was in a hurry and just wanted 'something' that was affordable and had a good chance of surviving long enough to gather other vital data. I have seeen the CC 110A on Ebay for $180, and although I recognize it has many great features (and is 44V capable), the extra $140 puts it "out of range" for the college students I polled.

Thanks again Todd, for you help and inspiration....

[GGoodrum]

As for the photos, I didn't even realize they were gone until just recently when someone told me. Something got screwed up with my Flickr account. I'm going to post a thread with just pictures and videos of my builds so it's all in one place. The old threads were getting pretty cluttered with other stuff anyway.

Did you ever create this "consolidation" thread? I just went through all 22 pages of this thread, and there's not a single picture of your drive, not one. Why not just post them to E-S instead of using Flickr? Also, I went to to the "blog" link in your signature, but it seems to simply be a site for EV bike pics, which is great, but I didn't see any with your drive in it.

I guess the one question I have is why do you need a one-way in the roller, if the motor/roller assembly pulls back forward, when you let off the throttle? Is the roller still being "engaged" by the tire? What if the sliding distance is increased a bit, and a spring used to pull the roller completely off the tire, wouldn't that eliminate the need for a freewheel in the roller?

-- Gary

[EVTodd]

As for the photos, I didn't even realize they were gone until just recently when someone told me. Something got screwed up with my Flickr account. I'm going to post a thread with just pictures and videos of my builds so it's all in one place. The old threads were getting pretty cluttered with other stuff anyway.

Did you ever create this "consolidation" thread? I just went through all 22 pages of this thread, and there's not a single picture of your drive, not one. Why not just post them to E-S instead of using Flickr? Also, I went to to the "blog" link in your signature, but it seems to simply be a site for EV bike pics, which is great, but I didn't see any with your drive in it.

I guess the one question I have is why do you need a one-way in the roller, if the motor/roller assembly pulls back forward, when you let off the throttle? Is the roller still being "engaged" by the tire? What if the sliding distance is increased a bit, and a spring used to pull the roller completely off the tire, wouldn't that eliminate the need for a freewheel in the roller?

-- Gary

Nope, never did get around to making a new thread. I'll get around to posting them some time. To be honest, I've been using most of my spare time trying to get in as much riding as I can before the weather turns to crap.

I suppose you could get by without the clutch bearing in the roller. As long as your sliding action is smooth enough and the motor is strong enough to pull it over a bit, it should work fine. A swinging motion is probably better for that kind of a setup though since you would have gravity helping to pull the motor down on the tire but hey, give it a shot.

As for my blog. That's been a bit of a flop. I started it for the heck of it as a way to showcase lots of different bikes (not just mine) but I've had very few posts to it. I'll probably let that go away after a while or maybe I'll switch it over to just my bikes. Actually, I never thought about that before... Might be more fun.

[Jehu]

G'day EVTodd,

Just wondering if you had put the photos up elsewhere? would love to see them as I'm looking at making something similar.

Or did I miss it?

Thanks Jehu

As for the photos, I didn't even realize they were gone until just recently when someone told me. Something got screwed up with my Flickr account. I'm going to post a thread with just pictures and videos of my builds so it's all in one place. The old threads were getting pretty cluttered with other stuff anyway.

Did you ever create this "consolidation" thread? I just went through all 22 pages of this thread, and there's not a single picture of your drive, not one. Why not just post them to E-S instead of using Flickr? Also, I went to to the "blog" link in your signature, but it seems to simply be a site for EV bike pics, which is great, but I didn't see any with your drive in it.

I guess the one question I have is why do you need a one-way in the roller, if the motor/roller assembly pulls back forward, when you let off the throttle? Is the roller still being "engaged" by the tire? What if the sliding distance is increased a bit, and a spring used to pull the roller completely off the tire, wouldn't that eliminate the need for a freewheel in the roller?

-- Gary

Nope, never did get around to making a new thread. I'll get around to posting them some time. To be honest, I've been using most of my spare time trying to get in as much riding as I can before the weather turns to crap.

I suppose you could get by without the clutch bearing in the roller. As long as your sliding action is smooth enough and the motor is strong enough to pull it over a bit, it should work fine. A swinging motion is probably better for that kind of a setup though since you would have gravity helping to pull the motor down on the tire but hey, give it a shot.

As for my blog. That's been a bit of a flop. I started it for the heck of it as a way to showcase lots of different bikes (not just mine) but I've had very few posts to it. I'll probably let that go away after a while or maybe I'll switch it over to just my bikes. Actually, I never thought about that before... Might be more fun.

[EVTodd]

I'm finally starting to think about ebikes again now that the weather is getting better. I just took my drive apart to get it all ready for spring and noticed that my motor's stator is loose on the bearing shaft (I hope that's the correct terminology).

Can you glue the stator back on to the shaft? It looks like it was just a press fit but it moves pretty easy now. I keep saying it's probably time for a new motor but I may as well keep going with this one if I can.

My plan is to use some epoxy on the bearing shaft then push the stator back on. Any other suggestions or is it even worth messing with at this point?

[Thud]

EVTodd,
The stator is normally jus epoxyied onto the bearing tube..so your proposed fix should work fine.
High temp suff would be 1st chioce.

[EVTodd]

EVTodd,
The stator is normally jus epoxyied onto the bearing tube..so your proposed fix should work fine.
High temp suff would be 1st chioce.

Thanks for the quick reply! Good deal. After doing a little reading it looks like it doesn't take a whole lot of glue either.

I was just looking at the motor again. I don't see a single trace of epoxy on the stator or the bearing tube. I'm surprised it held together as long as it did.

I wish they would start thinking about using mechanical means of holding these cheap outrunners together instead of glue. I mean, how hard would it be to make them with a set screw in the stator so you don't need glue? It would also be great to see the magnets set it pockets so they couldn't move. Oh well, I guess that's why they're cheap.

[def215]

hey todd,

hows the mystery controller holding up on the other bike? just curious to find out what the long-term update of that is. i was using the mystery 80a on my friction drive setup and i appeared to have fried one of the phases(ive shouldve heeded the warnings on rc setups not to go just partial throttle on them. )

[EVTodd]

hey todd,

hows the mystery controller holding up on the other bike? just curious to find out what the long-term update of that is. i was using the mystery 80a on my friction drive setup and i appeared to have fried one of the phases(ive shouldve heeded the warnings on rc setups not to go just partial throttle on them. )

We haven't been using our bikes since fall but the gf logged quite a lot of miles on her bike before that point. I'll be able to give you a better answer as the weather warms a bit around here.

[etard]

Good to see you back at it Todd, any new ideas you will be implementing?