kfong
100 kW
Do you have a link for the friction roller shaft. I might do one of these just for the portability.
Friction drive outrunner setup. New DJ bike.
- Thread starter EVTodd
- Start date
kfong said:
This is the only seller I've seen lately that still has them: http://cgi.ebay.com/10-Drive-Roller...5|66:2|65:12|39:1|240:1318|301:1|293:1|294:50 It looks like they're getting to the end of their inventory and selling off the blemished ones. I used to get them from Surplus Center but they seem to be gone now too.
Ok... I finally got off my butt and got a test setup and very short ride in a few minutes ago (had to be quick, it's about ready to rain). All I can say is HOLY CRAP 
! These little motors put out a ton of power. It easily went over 30 mph but I didn't want to push too hard until I got everything buttoned up. But, if it all holds together it's going to be a lot of fun. More power than I need actually, but hey, I don't HAVE to use it all the time.
After the ride my hv85 flashed and gave me a beep or two. I need to print out the error codes and see if it does it again. Not sure if I pulled too many amps or hit the cutoff (I thought I set it right in the software but maybe not).
Someone in a different thread was asking about outrunner noise. I'd say this motor is about twice as loud as my Kollmorgen but it's not bad.
One quick question. I seem to recall reading that you shouldn't use an on/off switch between the battery and the controller. Is that because you'll wreck the switch with the sparking or will it hurt the controller?
! These little motors put out a ton of power. It easily went over 30 mph but I didn't want to push too hard until I got everything buttoned up. But, if it all holds together it's going to be a lot of fun. More power than I need actually, but hey, I don't HAVE to use it all the time.After the ride my hv85 flashed and gave me a beep or two. I need to print out the error codes and see if it does it again. Not sure if I pulled too many amps or hit the cutoff (I thought I set it right in the software but maybe not).
Someone in a different thread was asking about outrunner noise. I'd say this motor is about twice as loud as my Kollmorgen but it's not bad.
One quick question. I seem to recall reading that you shouldn't use an on/off switch between the battery and the controller. Is that because you'll wreck the switch with the sparking or will it hurt the controller?
recumpence
1 GW
A switch will not be able to give you the power you need for the millisecond pulses of high current drawn from the FETs.
Glad you are having fun! Once you go with RC motors, you never go back.
Matt
Glad you are having fun! Once you go with RC motors, you never go back.
Matt
recumpence said:
Thanks Matt,
Maybe that's why I threw an error code on the controller. I do currently have a switch hooked up. I guess my next question is how can you wire a kill switch? (one that actually kills power from the battery) Because I need one for sure.
Another quick test ride today. I'm still shocked by the speed and power. It feels more like a quick scooter now. Fun stuff. I'm just hoping I still get decent range out of my batteries.
I have another (hopefully not stupid) question. I'm using a cheap servo tester with a 5k pot throttle connected to it. The servo tester needs a 10k pot to reach full throttle. Is there any way to use a resistor or something to make the 5k pot the equivalent of a 10k pot when it's turned all the way? I know, I know, I could replace the pot inside but I'm hoping for a quick fix.
I have another (hopefully not stupid) question. I'm using a cheap servo tester with a 5k pot throttle connected to it. The servo tester needs a 10k pot to reach full throttle. Is there any way to use a resistor or something to make the 5k pot the equivalent of a 10k pot when it's turned all the way? I know, I know, I could replace the pot inside but I'm hoping for a quick fix.
swbluto said:recumpence said:
Indeed. It's funny how R/C motors are just oh supposedly so much worse than hub motors, but then it seems like everyone who has gone the R/C motor route never goes back. I know I'm not.I wonder if that says something...
Yup. I'm pretty excited now that I've actually tried one. I think my cheap friction drive would shock a lot of people that have hub motors. Not to mention that I have zero drag from the motor when I'm not using it. If I run out of battery it feels like a normal bike (it's pretty darn light now too). I would declare my bike the fastest friction drive around but I recall Matt saying he has a friend with one that goes over 40 mph.
Like I said, if everything holds up I'll be thrilled with this setup. I think it's about the best bang for the buck. Here's what I have in it so far:
Castle HV85 $100.00 used on Ebay
3 Bosch Fatpacks $135
TowerPro Motor $48
Epoxy for magnets
$3.00Servo Tester $6
Misc Aluminum $10 (probably less)
Bearings for mount $14 (got 10 for that price, only used 2)
Ev Warrior roller $4
Throttle $10
Total $330 give or take a bit for misc hardware.
I think that's pretty cheap for a bike that goes over 30 mph.
recumpence
1 GW
Hey Todd,
You can check to see if your controller is seeing full throttle by looking for the LED on the controller board to light up. If it lights at full throttle, you are fine.
As for kill switch, you can use a large contactor. For me, I just make sure the battery leads are within reach to pull the plug if I need to. I have had to do that once.
Lastly, yes, the guy who bought the PK has a 50+ mph friction drive recumbent.
Matt
You can check to see if your controller is seeing full throttle by looking for the LED on the controller board to light up. If it lights at full throttle, you are fine.
As for kill switch, you can use a large contactor. For me, I just make sure the battery leads are within reach to pull the plug if I need to. I have had to do that once.
Lastly, yes, the guy who bought the PK has a 50+ mph friction drive recumbent.
Matt
recumpence said:Hey Todd,
You can check to see if your controller is seeing full throttle by looking for the LED on the controller board to light up. If it lights at full throttle, you are fine.
As for kill switch, you can use a large contactor. For me, I just make sure the battery leads are within reach to pull the plug if I need to. I have had to do that once.
Lastly, yes, the guy who bought the PK has a 50+ mph friction drive recumbent.
Matt
Matt,
The throttle has been working fine but I decided to make a nice one like you had on the PK Ripper. I'm sick of the flimsy made in China ones. I'm not sure how you had your setup but I'm using a brass gear reduction from the lever to the potentiometer. It should have a nice feel to it if I can find the correct return spring.
lesdit
100 W
Nice and clean setup. I used to have the 'Zap' friction drive kit about a decade ago, it had one motor on each side of the roller. It worked well, even off road.
It highlights the main issues with high rpm motors : We go through a lot of efforts with dual gear reductions etc, and then we send that power
to a *huge* speed increase sprocket called ' the wheel with the rubber tire on it ' ... :wink:
Did you calculate what rpm your setup runs the motor at ?
It highlights the main issues with high rpm motors : We go through a lot of efforts with dual gear reductions etc, and then we send that power
to a *huge* speed increase sprocket called ' the wheel with the rubber tire on it ' ... :wink:
Did you calculate what rpm your setup runs the motor at ?
The rpms for this motor at 36 volts should be around 8460. According to my calculations it should give me a tad over 31 mph (no load) with the size roller I have (1.25"). On the test runs I've been on it's gone over 30 easily with more throttle left. I'm not sure where the difference is coming in to play (maybe my cheap speedo isn't very accurate). It's faster than I need anyway but I'll have to do a run with my gps when it's all done.
Storm said:
It's simply mounted to the rear rack using two grade 8 bolts. The cheap rack in the picture is nice because it has square steel beam running the length of it. I was using a more expensive aluminum rack but I had to machine adapters to fit the round stock they used for the beam.
They're not in the photo but I also have aluminum uprights that connect the frame's lower rack mounts to the rack. I like to use these to make sure the rack never pivots one direction or the other (and to hold the panniers).
I'll get more detailed pictures up soon.
Storm said:So I see, mounted by a piece of angle, NICE
Yup, just simple 3" channel machined for 1/2" id bearings for the ev roller shaft to sit in. Pretty simple really.
As for the rollers, you can still get them on Ebay. I think that seller is down to the blemished ones he has left over but they would still work just as well. It wouldn't be that hard to make them from scratch either but the clutch bearing would cost more than the whole ev warrior roller. It's also handy that they have grooves machined in the shafts for pins. Those hardened shafts are a real bit%* to machine.
I am a bit worried that the clutch bearing might not hold up to the power of an outrunner but so far so good. If nothing else I'll press two of the bearings into the roller.
paultrafalgar
10 kW
Matt, don't suppose you could persuade some pics of that out of him? Was it a bike or a trike?recumpence said:Lastly, yes, the guy who bought the PK has a 50+ mph friction drive recumbent.
Matt
paultrafalgar said:Matt, don't suppose you could persuade some pics of that out of him? Was it a bike or a trike?recumpence said:Lastly, yes, the guy who bought the PK has a 50+ mph friction drive recumbent.
Matt
I would also love to see photos of his friction drive setup if you have them Matt.
Although an RC/Friction-drive would not be my first choice...in view of a recent E-bike theft thread from an owner who lived in a rough neighborhood, this set-up could be made with a quick-disconnect arrangement to easily carry the motor with you, along with a small battery pack.
Whether you want the motor/battery with you at work, or at home (some builders live up many flights of stairs and lock bike up at ground level) that makes this an interesting option for some...you could even purposefully use a cheap thrift store bike until you move to a better neighborhood.
Whether you want the motor/battery with you at work, or at home (some builders live up many flights of stairs and lock bike up at ground level) that makes this an interesting option for some...you could even purposefully use a cheap thrift store bike until you move to a better neighborhood.
spinningmagnets said:
I think most people feel the same way about friction drive but now that I've used one for quite a while I really don't see many advantages of using other drives. The only thing I've found (and I've said it a million times
) is that it isn't good in the wet. It's been great for everything else. I think roller drives got a bad name from really cheap, poorly designed commercial systems and diy hacks that are even worse. Actually though, I think people want something more exotic for that brag factor (which is cool too) but if the simple way works, I'm there! :lol: But yeah, in a high crime area you could easily make a self contained drive. Just have it mounted to a rack with a quick disconnect on your throttle cable. Pull the cable out and take the rack off. Heck, when I took my Kollmorgen drive off to start on the r/c conversion it took me less than one minute to get down to a bare bike.
deVries
100 kW
Hey Todd,EVTodd said:Quick photo of the test setup:
The final version will be hidden by my panniers (with the batteries mounted low inside them) so I thought I better get a picture before there's nothing to see.
I'm so impressed with this design of yours that...
I want to try a build like yours,
but I'm limited not able to do the bearing or motor shaft installations. (I don't own or have access to any machining equip -much less experience doing that skill set.) Would you consider doing a mount if I send you the roller and parts for some $ ? (Or, anyone else that can do this -please- pm me.) What brand/model of bike rack is that?
Thanks!
