Thanks! I had the VESC set to ADC. Changed it to ADC and UART, and now I have data. Now I need to go for a ride!Kepler said:Make sure you have set the App to ADC and UART. Also make sure you have Baud rate set to 115200.
Thanks! I had the VESC set to ADC. Changed it to ADC and UART, and now I have data. Now I need to go for a ride!Kepler said:Make sure you have set the App to ADC and UART. Also make sure you have Baud rate set to 115200.
I should have said "using the Metr app on my Android phone". I'm just planning to collect data, not change parameters on the fly (for now anyway)...c_saayman said:What Android app are you using? Are you able to connect with the VESC app? It is very easy to use and just works. My Metr App also connects and works, but I haven't really looked at it yet. I've done nothing special.
Kepler said:Hats off to the analogue approach but maybe consider going down the Arduino path. Opens up endless possibilities to how you control the drive. You don't need to be a programmer either with the block programming solutions now available.
Nice looking conversion! How did the ISCG mount work out?c_saayman said:So I took the bike for its first test run. The best part of the bike is that it still has the feel of my original bike, just a bit heavier.
With this new bike if you want power you need to spin the chain ring fast to get the motor working. It reminded me of the spinning gym classes when I though people were crazy torturing themselves like that. I don't think this is a bad thing. I can only get better.
With my gear ratio not being so good as FZBob (10T/90T - 32T-50T) I need to pedal a bit fast to get the same power.
FZBob said:Nice looking conversion! How did the ISCG mount work out?c_saayman said:So I took the bike for its first test run. The best part of the bike is that it still has the feel of my original bike, just a bit heavier.
With this new bike if you want power you need to spin the chain ring fast to get the motor working. It reminded me of the spinning gym classes when I though people were crazy torturing themselves like that. I don't think this is a bad thing. I can only get better.
With my gear ratio not being so good as FZBob (10T/90T - 32T-50T) I need to pedal a bit fast to get the same power.
I like your battery holder, very clean integration. Do you have any more pictures, especially of how the batteries fit inside? Details? What's it made of?
Any chance you can experiment with gearing the bike down a bit? Maybe try a 28T chainring on the front, and try a 9T on the motor? (Just for research...) I have re-geared every bike I have owned since the '70's in order to make climbing easier. I know that with a 1x drivetrain, you would loose top speed, but it might be worth the tradeoff.
I do recommend removing the chain when working on the stand with the battery connected. It doesn't take long, and could prevent an accident.
That's a nice pack. It really blends into the bike. Looks like I need to learn about 18650 cells as an alternative to RC batteries. It seems like the most difficult part is spot welding tabs to the batteries.c_saayman said:The battery was custom made from 18650 Sanyo 3400Ah cells - 4S4P, fitted inside a 30mm x 50mm rectangular tube. Animalector spot welded the cells for me. He has done a great job. The biggest BMS that fitted into the tube was 40A. The battery is a bit heavy, but I wanted it to be as solid as possible.
The 12 speed SRAM chainring I'm using is an X Sync 2 and it only goes down to a 32T. I have not seen any other smaller 12 speed chainring yet. Not sure if the chain is anything special. I'm not very impress with the SRAM NX 12 speed drive train. I would like to convert it to a 11 speed Shimano XT drive train with a 11T-46T cassette and maybe 28T or 30T on the front. At this stage it is just too expensive +/- $500
I will still try the 9T on the motor. Just haven't manage to cut the key into it yet.
I believe the North Shore spider has both 104 BCD and 64 BCD mounts. This would allow for a 26 or 28 T chainring on the 64 BCD mount, and the Rebel sprocket on the 104 BCD. (Possibly even a 38T and 26T 2x setup and the 90T Rebel sprocket, with an ISCG mount front derailleur, if it all fits...).c_saayman said:Thanks for the info. I will have a look. I like the Wolftooth products. I am using a 104 BCD spider. The new Rebel sprocket is also a 104BCD, so I would like to stay with this mount. The smallest I've seen on a 104BCD was 30T, with the spider interfering with the chain. My SRAM chainring is having some really funny looking teeth.
The 10T motor sprocket I'm using is a bit different then yours.10T motor sprocket.JPG I had to drill through about 10mm and then file it out to make the key. The 9T I'm using seems to be from a much harder metal, and the drill was not making a dent. Something worth mentioning is that I've placed a rubber o-ring on the narrow part (like you did) and the motor and chain are very quite. I sometimes don't even know that it is on.
c_saayman said:Polygon finished!
I have fitted the 9T sprocket on the motor and the 30T chainring. It all works very well. The 9T works better, but as mentioned by everyone else, it is more noisy. All that's left now to do is to ENJOY IT!
What is your goal? A bit of assist to help out on hills and make pedaling a bit easier, or big serious power so you can go FAST?cheapcookie said:I'm planning out a fixie build with sick bike parts cranks. [strike]The biggest cog I found for the hub is 22T 3/32 chain[/strike].
Assuming wolf tooth 30T with the 3/32. And lets say 53 rebel and 9T motor sprocket, I'd be going pretty fast on 10s.
26in 2.4 wheels.
1200Rpm at the wheel I think, is this a good idea ?
edit: here's how I make bigger cogs http://www.63xc.com/jasom/grannycog.htm, so my new question is what single speed cog do I want
Got it. The VESC 6 does look interesting. Just curious - is this your main transportation or a toy? Are you OK with the time and expense of a development project?cheapcookie said:Sorry I dont want 93mph at all, 1200*60*0.000695km= 50Kmh? going close to 40mph is of interest to me.
I am highly interested in the vesc6 and power dense motor
FZBob said:A month ago I posted some data on VESC heating vs power. It looked like this put a limit on continuous power. That was using a 4s battery.
I was curious to see if changing from 4S to 6S (NO gear ratio change) would improve things. More Voltage and less current... So I ran a quick & dirty experiment. 500+ watts up a short steep hill, same speed, same gear. I collected data from the METR. (numbers are not exact, as I was picking them off a chart)
4S:
Battery Voltage: 15.5 Volts
Battery Current: 34.5 Amps
Duty Cycle: 60%
Motor Current: 68 Amps
VESC Heating Rate: ~2.5 Degrees/Second
6S:
Battery Voltage: 23.25 Volts
Battery Current: 23 Amps
Duty Cycle: 40%
Motor Current: 70 Amps
Vesc Heating Rate: ~2.55 Degrees/Second
Not a big surprise. It looks like just adding battery voltage doesn't make much difference. Battery current goes down, but motor current remains the same. Heat rate apparently goes with motor current. The bike also felt about the same.
It looks like the path to more power is more RPM, while keeping the Motor Current/Torque low. This would also keep the stress on the #25 chain down. Maybe using a freewheel crank for a second stage of reduction, as cheapcookie mentioned, although this will spin too fast to allow for pedal assist at high speed. Might make an interesting commuter though...
All six of my motors have sensor cables. Five of them have six wires in the sensor cable, which I believe indicates they have temperature sensors. As I run sensorless FOC, my sensor cable is not connected...cheapcookie said:Interesting, do some of these outrunners come with temp sensors? whats the motor heating rate 4svs6s?