39mph w/Ebay motor and Lyen sensorless controller

[snellemin]

30 psi was really comfortable and you could barely tell it was "low", while still feeling stable. But I must say that 50 psi does feel smoother.

[o00scorpion00o]

38-40 mph is a lot of fun isn't it ?

I must say that I like the fact the mac can do that on 16S, though I miss the regen of the pie, I need to install Doc's beastly torque arms for it as there is slight movement in my own torque arms that only matters with regen but I'm keeping them for a future project.

I would keep at least 50 psi to save more battery, beside you got a rear suspension.

I had a bike like yours with the same type of suspension and it made me bounce way too much, there was no control on the spring, If you could upgrade the rear shock I bet it would make it a lot more stable!

The reason I got rid of it was because I couldn't upgrade the front forks because it's impossible to find decent forks in a 1" steerer!

[snellemin]

I made a monster cap bank for my bike. Bike is way more responsive now at launch and no more power cutoff at startup. I used 19 100V 1500uF caps.

[o00scorpion00o]

Holy crap!

That's cool, I would imagine an incredible spark connecting to the battery?

Did you have a lot of voltage sag to begin with ?

Is the voltage much different ?

[snellemin]

I wasn't having issues when I was running lower voltages. It's when I started going up in voltage that I was having throttle issues. I had to gradually increase my throttle to get up to speed. Not an issue in zero traffic, but kinda annoying in heavy traffic. Happens with both lipo and A123 power source.

I use a precharge resistor, so still no spark.

[o00scorpion00o]

I wasn't having issues when I was running lower voltages. It's when I started going up in voltage that I was having throttle issues. I had to gradually increase my throttle to get up to speed. Not an issue in zero traffic, but kinda annoying in heavy traffic. Happens with both lipo and A123 power source.

I use a precharge resistor, so still no spark.

Hmm, I wonder is it the fact your hot voltage is around the limit of 100 volts?

Did it happen after you ran down the pack a bit ?

[snellemin]

It's intermittent when the voltage dips a bit or running a bit less voltage. I can then use the CA to tweak it a bit and totally get rid of the issue. But I missed the hard throttle response, which made me build a cap bank.

[o00scorpion00o]

That's strange, have you said mentioned it to lyen?

He might be able to build you a higher voltage controller, or get a Kelly, but a Kelly at that power level will cost a lot!

[snellemin]

I've told Lyen about it. He said that I triggered the overload protection, which happens when the fets get stressed out. I figured I was getting some crazy ripple current, stressing the whole controller out. So I build a Cap bank, just like I build them for my high amp RC toys setups.

[o00scorpion00o]

The fet's are rated for 150 volts I thought?

The caps at 100 or so.

[snellemin]

That is what Lyen told me. Dunno, but I'll see today how the caps work on my way to work.

[snellemin]

From a slow roll I hit the throttle and saw peaks of 3850W with 28s2p A123. But I'll be riding on 24s2p A123, which is still fast enough for me.

[o00scorpion00o]

That is interesting,

My mac pulls 3500 watts on 16S LiPo, still a fair bit less voltage than yours!

That's good to know though for future projects, thanks for sharing!

[snellemin]

It was great riding to work. Very responsive throttle and it pulls hard. Had a good tailwind and was doing 40.9MPH on 74.6V.

[o00scorpion00o]

Yeah the pie is a great motor al right

I may buy back the pie from my friend and drill the covers, I bet it will take a hell of a lot of power!

Remember it pulled me up a 16% grade (3kw) for 2 miles and survived, granted it did smell funny and I burned the halls, but next time I'll drill the covers, something you should think about if you are worried about heat!

Maybe 20S would help me get up faster!

But anyway that was the extreme!

[snellemin]

Youtube link of my commute home http://www.youtube.com/watch?v=05IY79aQ3kk&hd=1

[o00scorpion00o]

Youtube link of my commute home http://www.youtube.com/watch?v=05IY79aQ3kk&hd=1

Hi Snellemin,

I can't see the vid as YouTube seems to be bad here today, sometimes I find YouTube is brutal slow, or maybe my ISP throttles YouTube ?

Anyway, how are you getting on with the capacitors?

You didn't have much sag with those cells did you ? Or was it purely because of the high voltage ?

The a123 cells should be well up to the job ?

[snellemin]

You could try to play the lowest quality 360 mode on youtube.

The caps are great. For fun I didn't use the precharge cap and see what it would do. Holy crap, I almost welded the plug together.
I had no issues with the batteries before the caps. Just when I went with a higher voltage I got some stuttering at hard throttle. I'm sticking with 26s2p A123's now, which gives me 40-42mph with a tailwind and 36mph with a headwind. Controller will also be less stressed with the additional caps. Build a cap bank and try it out.
The A123 are well up to the task. I use them in my RC toys, drag racing 1/8 scale. My 4s2p A123 setup beats any lipo setup off the line where it counts. Check out my other vids on youtube.

[snellemin]

Here's another vid of my commute to work
http://youtu.be/xRTXv4YJk3Y?hd=1

[o00scorpion00o]

You sure have good roads and nice weather!

I don't know if I would be comfortable riding with traffic in the middle of the road though ?

The sensorless controller seems to work really well, which is good to know!

Most of the roads (lanes) or whatever you would call them don't have a lot of traffic and are barely wide enough for 2 cars to pass, only thing I have to really be careful of are tractors with big machinery behind them

[snellemin]

The weather has been nice lately. Here is another vid of me heading home last nite http://youtu.be/v7Wcuzikyuw

The sensorless controller is really nice and as you can see I have no need for a sensored version.

[o00scorpion00o]

hah I saw the lad on the motorbike trying to get you to race him, I couldn't see who pulled off quicker ?

I still think I would be too nervous to ride an electric bicycle at speed on those roads, especially at night ?

How would drivers know you were stopping hard ? and indicators ? hmmm how bout a vectrix ?

I think if I had those roads that it would be safer to buy an electric scooter. There isn't even a shoulder to ride in, and no bicycle lanes, almost as bad as here!

You didn't get regen going did you ? I had a bike like that with V brakes,

But hey, it's running well now, congrats!

[snellemin]

The guy on the bike just complimented my ride and was suprised it went that fast.

I have a bright red flasher on the back of my helmet and one on my rear of my bike. The bag is reflective and the tires have the reflective line around them. My wife's bike has the brakelight, but it tops out at 17mph or so.

I didn't get the regen done. I think I would blow the controller if I did. One day I'll get a new fork to fit disk brakes. My regular mountainbike has hydraulic brakes. Go figure. You can see that bike at the beginning of this vid--> http://youtu.be/_QGhAKWwow0

[o00scorpion00o]

Yep, that's the kinda bike you should have your pie II on, I know it's a hardtail, but the stopping power of hydraulics is essential, in my opinion anyway, especially here where it's wet more than dry!

I found on the full suspension bike I had like yours, the back shock was far too bouncy, while better than no suspension, was just bouncing all over the place, the handling was too bad, but yours might be better. The frame I found was far too weak too. But I suppose the 10 kg ping didn't help on the seat post!

That hard tail though looks the job. You might even be able to mount the batteries in the frame with the falcon ev bag!

[snellemin]

The hydraulics in the rain and mud is best, but I don't ride my ebike in the rain. My ride is pretty smooth with the rear shock set stiff and running on those sticky 2.3 Michelins.
I do have my old ebay motor still that I'm sometimes wanting to add to the hardtail. But that is my bike I ride the trails on with my son.