Pikes Peak, Electric Mountain Climbers...

[neptronix]

According to the ebike.ca calculator, that's what i need to go for the ~25 miles at a 7% constant grade, doing about 25-30mph.

Average constant power should be between 2000w and 4000w.
Laptop cells are a no go due to their size, and especially their discharge rating. 1.5-2C constant draw will just turn a lot of stored energy into heat from internal resistance and possibly even blow the pack..

It's already going to be a big challenge to fit the lipo in the triangle bag, the rear rack, and my backpack!

 

[amberwolf]

Oh, well, it was a thought, since I already have at least a couple KWh of laptop cells that should be good enough to use, and it probably wouldn't be hard to come up with more.

If you need up to 4KW peaks, that's what, 45A? and 22-23A sustained?

So to keep it well under 1C, it'd have to be at least 25p, maybe 30p, for sustained use. 40p to 50p to deal with peak loads, if those have to stay under 1C.

At 24s 30p, that'd be...720 cells; if they're 1.2Ah each @ 3.7V nominal, it'd be 3200KWh or so of cells just for that. Potentially double. I'd guess that the 300 cells I got first probably weigh 15lbs or so, maybe more? So at least 40lbs for just that pack, possibly up to 80lbs for a pack to keep peak loads at 1C or less.

I guess that would be kind of a largish pack. :lol:

 

[John in CR]

...We're only talkin' bout a few percent here and there..

Not with the CVT. About the only efficiency number ever squeezed out of NuVinci was a 10% loss at peak efficiency. Pedalists can feel the drag. That's not to say it can't lead to much greater efficiency in everyday ebike riding, but this climb is about proper gearing. With a good speed wind hubbie in a small tire, you gear for peak power rpms to be achieved up a 11%-12% grade, and you're looking at efficiency never dropping below about 75% and mid 80's most of the time, so no way a double digit hit in the drive train would be acceptable.

 

[John in CR]

Amberwolf,

You're looking at just getting to the top, not breaking the speed record, right? Lower speeds require much lower power, just as Opti proved. Use the power calculator here http://www.kreuzotter.de/english/espeed.htm . Down in the pink section delete the power and input the speed on the first pass, and then it spits out power requirements. You'll quickly see you want your lightest rig, and then maybe a big enough pack of your lower power cells could work.

 

[neptronix]

lol yes it would be..

Cheap yeah.. small, powerful, and light that stuff isn't.. unless we are talking about some of that 200wHr+ new gen stuff. But even those batteries have a maximum continuous discharge rating of 1C... lol.

In lipo weight, i am looking at a low 40lb figure.

The upside is that after buying all those packs i'll have what, 2-3kwhr? would be enough for a scooter build.. if i was crazy enough to Actually keep that much lipo on my premises anyway :lol:

 

[John in CR]

. if i was crazy enough to Actually keep that much lipo on my premises anyway :lol:

If the packs are well spaced, nothing flammable within reach, and good ventilation, then the risk is low. My flameout pack was inside and unattended (just sitting there for weeks, not on a charger). It was spaced a few inches away from other packs, and only the 1 cell flamed, the one under it puffed, and the bottom 2 cells are fine. Other than the 2 lost cells, I lost a couple of connectors from nearby packs that extended too close.

 

[Jay64]

Wait, you had a pack of Lipo flameout just by sitting there, it wasn't even on a charger? I thought these were pretty safe unless you discharged them too hard or charged them too hard.

I don't think my current build will make the whole trip, that's why I was thinking of doing some smaller test runs. See how much power it was actually using for a shorter part, see how it effected the motor ect. Test to get data, not to push things past their limits.

 

[dogman dan]

Good point about storing the lipo with a bit of space between. A simple but obvious precaution that was not obvious enough for me to think of it. I have, since reading about your single pack that flamed, begun storing my lipo in ammo cans, with holes drilled to vent them, in 700 wh blocks. At least it won't all go off in one big fire. Just one boxfull.

Johns pack that flamed was clearly a defect, I feel pretty good about all my known to be good packs. Bad ones, ones with puff or one bad cell are stored in a different metal box from the others.

 

[Tom Tom]

Found another guy who rode electric up:


http://www.petesebikes.com/blog/item/assault_on_pikes_peak_2011/

 

[amberwolf]

You're looking at just getting to the top, not breaking the speed record, right?

Actually I was thinking of building up packs that could be sent to Neptronix or someone for their attempt on the ride. I don't have the skill to ride up those trails, I think, not with the possible other traffic on there--I'm a flat-paved-road kinda guy. :lol:

Cheap yeah.. small, powerful, and light that stuff isn't.. unless we are talking about some of that 200wHr+ new gen stuff. But even those batteries have a maximum continuous discharge rating of 1C... lol.

Well, it was a thought. :lol:

Buuuttt....the cells Jay64 has are the NMC stuff from EIG:
http://www.eigbattery.com/eng/product/3.jpg
http://www.endless-sphere.com/forums/viewtopic.php?p=473502#p473502
which are 5C sustained, 10C burst. At 20Ah/cell, that's just fine for this ride. :lol:
Assuming that at 5C you won't get the full 20Ah, let's just say 15Ah to be super-pessimistic *and* to leave plenty of clearance on the low end of charge state, it'd take about 48 of those cells (assuming 24s) to get you 30Ah, and you'd probably have closer to 36Ah or more safely usable.

But I don't know what they cost or where to get them--you'd have to ask Jay64.

 

[neptronix]

Found another guy who rode electric up:

http://www.petesebikes.com/blog/item/assault_on_pikes_peak_2011/

This guy only brought 12ah and finished in 3 hours..
Obviously not in it to win it, lol.

Amberwolf.. for those EIG cells, they seem quite good. 175whr/kg is a slight improvement over lipo. I'll bug Jay64 about where to get them. If the price is right, these would be pretty nice.

What i'd love is some 3C continuous NMC with 200whr/kg .... a man can dream...

 

[Jay64]

I've got 44 of those cells. I think carrying all of them at once is gonna be quite large for a bicycle. But, I'm gonna try it. I have some hard metal cases for them that make each one, 22 cells each, about the size of a deep cycle SLA. I'm going to try to test them on a relatively flat go-kart track and see how they do.

 

[amberwolf]

According to the spec sheet page, they would be just about perfect for going in my black powerchair-battery boxes currently on the sides of CrazyBike2.

And at basically 1lb per cell, 44lbs for 160V 20Ah, or 80V 40Ah, 3.2KWh, I'd somehow find it in me to live with the weight.

So if you ever find you just don't have room for them, I do. :lol:

 

[Jay64]

AW, I have about 30 assorted vehicles/chassis waiting for power. I'm sure I can find a place to put them. :wink: :lol:

 

[docnjoj]

Hey AJ
I resemble that remark!
otherDoc

LoL why am I not surprised...

KiM

Here is proof of another large old guy on a trike, AJ and Bigmoose!
otherDoc

 

[toolman2]

ive only just found and read all this, so sorry to roll up late but as an early pie fan (http://endless-sphere.com/forums/viewtopic.php?f=3&t=17311&hilit=80kph+magic+pie) i have some experience and info, the pie has an 18mm by 266mm stator and there are at least 2 windings.
the low speed is 7.5rpm/volt and .216ohm resistance, high speed is 13.4kv and .085ohms (you often get this one in small wheel sizes, but the copper fill is 26% worse unfortunately)

your dead right luke about its ability for the output of high torque due to its huge diameter and surface area for cooling. ive had 5.5kw power in, and it would hold 90kph on flat road, 100kph down a slight hill, and dyno runs with 4.2kw in, gave 3.5kw out.

the max torque i have seen is around 130NM, but more importantly for the job at hand is the max continuous torque is around 34NM for 150deg winding temp not drilled. seems low i know but this is the real world of CONTINUOUS and ACTUAL OUTPUT and thats very different to "my x5 runs way over 10kw"..

its good to see a bit of interest in the pie, as it does have some positives due to the large diameter, i kinda gave up a year or 2 ago trying to convince a very "keen on crystalites" ES fan base that there are other otions
- was ES started by a crystalite salesmen or something? it seems a little better now on this front so im hoping 2 years later to not be rounded up and shot/banned etc by speaking of golden motor :wink:
while im at it causing trouble, the new and much heralded HS35/HS24 is (i believe) just a regular old (sub $100 chinese) golden motor of the last 8 years with a 30mm by 198mm stator, putting it right in the middle of the 35mm and 24mm options from crystalite and shares the exact same internal design and structure. all perfectly good motors etc but not different enough to get too exited about.

anyway, more info and stuff to come on weather or not a lone pie can make the climb, i think your right though youll need to get a bit drilly and maby look a bit like a clown with a 16" wheel? :lol:

 

[AussieJester]

The name "Magic Pie" i think puts alot off sounds a lil
cheesy people might (incorrectly) relate that to poor product possibly?
Great to hear its worked well for you though Im sure
the info will be 'muchly' appreciated by many

KiM

 

[dennyt]

Only mildly related...

[youtube]P-TLmR6_Ufg[/youtube]

This looks and sounds just like a 1:1 scale Tamiya kit!

 

[TonyReynolds]

WOW! Real time, real fast! Great video!

 

[Whiplash]

High KV motor by the sound of it! High rpm lower amp draw with high torque from gearing!

 

[Hillhater]

Maybe i am missing something , but i dont understand why they have not opted for at least a 2 speed transmission.
That car is nowhere near losing traction accelerating out of the slow , hard surface, turns and a lower gear would give it much more torque at the wheels for the slow speed stuff. On the dirt sections, it seems to handle much better using throttle steer. Worrying to see so many spectators so close to the edge of a race track....risky....it reminds me of a Portuguese WRC event !

 

[liveforphysics]

ive only just found and read all this, so sorry to roll up late but as an early pie fan (http://endless-sphere.com/forums/viewtopic.php?f=3&t=17311&hilit=80kph+magic+pie) i have some experience and info, the pie has an 18mm by 266mm stator and there are at least 2 windings.
the low speed is 7.5rpm/volt and .216ohm resistance, high speed is 13.4kv and .085ohms (you often get this one in small wheel sizes, but the copper fill is 26% worse unfortunately)

your dead right luke about its ability for the output of high torque due to its huge diameter and surface area for cooling. ive had 5.5kw power in, and it would hold 90kph on flat road, 100kph down a slight hill, and dyno runs with 4.2kw in, gave 3.5kw out.

the max torque i have seen is around 130NM, but more importantly for the job at hand is the max continuous torque is around 34NM for 150deg winding temp not drilled. seems low i know but this is the real world of CONTINUOUS and ACTUAL OUTPUT and thats very different to "my x5 runs way over 10kw"..

its good to see a bit of interest in the pie, as it does have some positives due to the large diameter, i kinda gave up a year or 2 ago trying to convince a very "keen on crystalites" ES fan base that there are other otions
- was ES started by a crystalite salesmen or something? it seems a little better now on this front so im hoping 2 years later to not be rounded up and shot/banned etc by speaking of golden motor :wink:
while im at it causing trouble, the new and much heralded HS35/HS24 is (i believe) just a regular old (sub $100 chinese) golden motor of the last 8 years with a 30mm by 198mm stator, putting it right in the middle of the 35mm and 24mm options from crystalite and shares the exact same internal design and structure. all perfectly good motors etc but not different enough to get too exited about.

anyway, more info and stuff to come on weather or not a lone pie can make the climb, i think your right though youll need to get a bit drilly and maby look a bit like a clown with a 16" wheel? :lol:

Toolman, you kick ass, and you've always kicked ass. Thank you for this info.

 

[zombiess]

Toolman2 provided enough specs for me to decide and give it a go. Just placed my order for a 16" pie for use with an external controller. Simulator is estimating a flat ground speed of 55+mph with 24S LiPo and a 16" wheel and only 600W of waste heat. Gonna fire up the drill press when it gets here 8) Maybe a pump and mister too...

Guess I'm about to find out how dumb I really am. Maybe I should figure out how to run less than 100V setups... naaah

 

[sk8norcal]

[youtube]7pcCyGclsDk[/youtube]

[youtube]DsvMij3CZCE[/youtube]

 

[full-throttle]

I can understand why everyone hates them now

De-tuned to 250W :lol: Yeah, that's going to sell well
Batteries overheating? WTF?? Get some REAL cells
34.5mph "extremely fast" for the track The hour record is more than that - that's a guy on an un-powered bike for the full hour! Most racers sprint to 45mph
And who's the clown on a fixie in the background @ 2:00