"peak power" - Trek 4300 20" Magic Pie build.

[neptronix]

Damnit Z, you're totally right now that i look at it.

might do an extra millimeter ... that's about it :|

This is the other FS bike i bought recently. I think i can extend the rear to the point where i'm getting an inch or two of extra lift in the back.

Got no disk brake tab in the rear though. But with the farfle swingarm, the situation changes.

A local bike shop is also selling a 170mm manitou fork.. if you go with a 20" wheel, do you think it would be better to extend my fork 70mm? or maybe just keep the 100mm business on there to get a major front end drop with a 20" wheel?

 

[zombiess]

if you change both wheels to the same size, the geometry stays the same, no handling problems. Using the longer shock changes it a bit by shortening up the wheel base which can make you a bit more wheelie prone, but with a swing arm like Farfles which is 3" longer you don't need as long of an shock because the lever is longer and the wheel base will probably still end up longer.

Flip the K2 frame for profit on ebay.

 

[JohnC]

Nep,
Oldest son just picked up a 2100 on cL after reading your thread and others here. What was the asking price for the Farfle swingarm? Do you recall? Thanks

P.S. that makes 2 more ebikers in the family. Middle son, (e.s. dude) is doing a mongoose build.

 

[neptronix]

zombie: i get it. The rear gets a little lift though, so maybe the front deserves a bit of a lift to keep things even.
Well, i guess it's decided. I'm gonna make a hot shit Genesis v2100 :lol: . Some local dudes have offered to make me a monster swingarm, but i don't know how serious they are, we'll see. Farfle is still making the swing arms...

The K2 will be kept for the MAC build. Pretty much done with hardtails. The road conditions here are practically post apocalyptic, so i need a dual suspender. I will miss the Treks dearly; they are bombproof, full of space, have rear rack mounts, and making torque plates for them was *super* easy.

Gettin' a little weepy just thinkin about it :lol:

 

[neptronix]

Allright....

GT iDrive frame is sold.
K2 frame is too bent to use, bends in the triangle = problepeño. Returned to store. Full refund.

Picked this up for $20 at my local bike store.

11.75lbs ( w/shock ), and steel.. freaking insane.
Yup Zombiess, i'm gonna copy you :lol:
The local fabricator guys are gonna love working with this ( if the follow through! ). I will have to have it modified so that it fits me though. The welds on this thing are awful too. May have 'em touched up.

 

[neptronix]

BAHAHAHA.. girlfriend says "$20, huh? purple must not be a popular color with the homeless guys i guess"

 

[zombiess]

I bet my swingarm would fit that bike. Looks like the same design. Measure the pivot width. Once you get it right it's going to be a blast. Welcome to the $20 bike club .

 

[neptronix]

I forgot you still had the mad max welded up swingarm hanging around.

Gotta say, there is something nice about having something that is basically a throwaway. I can have it welded on, rattle can it black, scratch the crap out of it etc, at the end of the day who cares. Kinda liberating, coming from the viewpoint of seeing what you own as precious and fragile ( nice aluminum frame ).

I even have a rear "shock" from the genesis v2100 for it that is almost an inch longer. That in itself will change the geometry in my favor, like your idea.

I think this could work. I measured the frame.. it is only an inch smaller than the silver Trek 4300. Maybe it just looks smaller in pictures.

 

[zombiess]

That looks the same as mine. Easy and cheap to extend the swingarm.

 

[neptronix]

Well, if you have no use for your old swing arm, i'd be happy to give you some $ for it.

Looks like you have the 'Power X' Next bike. I have the 'Power Climber'. An entire $11 more brand new. Don't be jealous.
I think the only difference is actually just an extra tube.

p.s. i forget what you said about the head tube. You can just stick a 1 1/8 unthreaded fork in this bike, with the right headset.. am i right? my surly fork fits through..


http://endless-sphere.com/forums/viewtopic.php?f=30&t=38231

Auraslip, did you see this thread? it's got me inspired, big time, to stick with the pie.
Might help with other motors, even the 9C.
Methinks you could bolt some intake fans into the little holes in the 9C stator. You'd not need to make an aluminum plate like he did. The sucking motion near the windings and exhaust out the center... could work real well, drastically better than just drilling holes in it and calling it good.

Wire up those fans in series according to your voltage.. 12v x 6 = 72v... hmmmmm

 

[neptronix]

Do you see it, my man?

 

[veloman]

Would you consider using a 'pusher' trailer for this hillclimb? The downside is it may add a few pounds. BUT, it may not, if you factor in you could ride a 20lb road bike!

Check out my thread. You could slap your 20" Pie in there, easily strap on multi kwhs of battery and bam! You may have a traction issue at your power levels, now that I think about it....

I'm totally interested in this pusher trailer idea now, especially for cargo hauling. Way more efficient than towing an anchor of a 2 wheel trailer.

http://endless-sphere.com/forums/viewtopic.php?f=3&t=38243

 

[neptronix]

Thought about it for a short period of time.
Could easily put one together from a cut-up BMX bike.

But i imagine that there are odd handling effects that would be detrimental.... and yeah, the power is an issue, especially if i only have a bit over 30lbs of battery to stick on top of it.

 

[o00scorpion00o]

This thread has moved on a bit since my last visit, and I see your old trusty trek frame for sale!

Dave, I think I would consider the oil cooled magic pie first before messing about with fans and cromotor.

You need to do a few test runs, I can't believe you have not climbed any steep hills before making any decisions.

Install a temp sensor and take a few spins and then decide if the pie is for you or not, defiantly what I would do before spending more money, especially the amount of money for a cromotor.

The cromotor belongs on a scooter, not a bicycle!

The pie is as good a motor as you will get for a bicycle, if you want faster than 40 mph get a scooter and it would be far safer.

I wouldn't give up on the pie yet, especially since you have not really tested it in the environment it's supposed to be going up on the day!

 

[neptronix]

^--- i fully agree with you

I did actually find a hill worthy of testing just yesterday when i was driving up the mountain.

This is the steepest thing i have found thus far
Most people are going up this hill at about 20-25mph, so i should be going at the speed of cars.

This is my test hill now. There is also a ~10 mile version of this nearby, but i'm not sure if it's paved or not. I will investigate.

Honestly on the trek frame, i've been too nervous to take it up any hills. Just too damn squirrely. Been hunting down proper DS frames for months now. That has been a big hold up in taking this project further. The NEXT bike solves a lot of problems.

Are there any threads on folks installing temp sensors you've read lately? i'd like to see. You're right. I should have a sensor. And i should beef up the phase wires at the windings rather than the axle as well. Already had the motor apart once by now.

 

[auraslip]

https://sites.google.com/site/shelbyelectro/motors/mods/installing-a-temp-sensor-in-a-hub-motor

 

[zombiess]

The cromotor belongs on a scooter, not a bicycle!

Of course it belongs in a bicycle. What if you want to climb steep hills in a 26" wheel? Just because most of us are using them on our outlaw turbo super death ebikes doesn't mean they don't have a valid legal use. No electric scooter should come with a motor rated for less than 8kw continuous either, otherwise they are just too slow

50-60mph is perfectly fine as long as you build your bike right (custom fabrication) like most of the fast guys on here. Just don't try to put it in a Walgoose bike with rim brakes in a 26" wheel and feed it 100V@150A and expect everything to be rainbows and kittens :lol: Little details like proper dual 8" hydraulic disc brakes and decent full suspension travel front and rear become necessary.

Then again I've seen compliments given to someone on here who went 40mph with a horse shoe rim brake held on with nothing but zip ties

I have a quick question about the pie o00scorpion00o. Do they only come in one speed? Does the 16" or 20" come in any faster wind? I thought about building something with a 16" version, but I'd like to know if is a faster wind, otherwise it's hard to get the speed out of it I'd want. I asked GM Canada and they said they don't know, big help there :lol:

 

[neptronix]

I think it belongs on a bike but if you run it at the maximum power ( which zombiess has yet to find, apparently ) it's really dangerous.

I agree about the hill climbing comment. I wish i could afford one. It'd make this build a lot easier

I believe the magic pie comes in 1 wind only, given that me and scorpion's speeds are quite different per voltage.

 

[toolman2]

they used to do a higher speed wind of the pie when you ordered an 18" wheel, not sure if they still do that, but even then they have less copper fill.
you can change the normal pies to delta, it works well and we got about 13kv.

 

[zombiess]

they used to do a higher speed wind of the pie when you ordered an 18" wheel, not sure if they still do that, but even then they have less copper fill.
you can change the normal pies to delta, it works well and we got about 13kv.

Now that is an interesting idea 16" pie in delta could be fun.

 

[neptronix]

Hey.... don't you lose some efficiency in delta?

 

[toolman2]

Hey.... don't you lose some efficiency in delta?

yep, you are right in saying that mostly, but the std waveform of the pies is a sine wave, and it then turns out you get no extra losses.
-spent a bit of time spinning them to high rpm in the lathe (to amplify any difference) and noting the drag before and after the change, so we are in luck here, the pie loves delta.

but you do have to put new halls in, cos of the 30deg change in timing, but you may have to move them anyway for real high power, as they are in the middle of a tooth std
and i dont know if anyone has had the issue before but the halls can get false triggered by the windings and it misfires real bad over 100a.

the info needed should be visible in zappys fan cooled pie pics, you end up with .065ohms phase resistance and thats getting real low and can take a lot of amps.

 

[o00scorpion00o]

The cromotor belongs on a scooter, not a bicycle!

Of course it belongs in a bicycle. What if you want to climb steep hills in a 26" wheel? Just because most of us are using them on our outlaw turbo super death ebikes doesn't mean they don't have a valid legal use. No electric scooter should come with a motor rated for less than 8kw continuous either, otherwise they are just too slow

50-60mph is perfectly fine as long as you build your bike right (custom fabrication) like most of the fast guys on here. Just don't try to put it in a Walgoose bike with rim brakes in a 26" wheel and feed it 100V@150A and expect everything to be rainbows and kittens :lol: Little details like proper dual 8" hydraulic disc brakes and decent full suspension travel front and rear become necessary.

Then again I've seen compliments given to someone on here who went 40mph with a horse shoe rim brake held on with nothing but zip ties

I have a quick question about the pie o00scorpion00o. Do they only come in one speed? Does the 16" or 20" come in any faster wind? I thought about building something with a 16" version, but I'd like to know if is a faster wind, otherwise it's hard to get the speed out of it I'd want. I asked GM Canada and they said they don't know, big help there :lol:

You chaps are nutz!

Then again I used to think 40 mph was too fast on a push bike and here I am doing 40 on it, having said that it's not too steady on anything other than a smooth road, but I'm on 1.6 tyres pumped to 90 psi!

I used to think the Pie came in different speeds, but according to nep his is a good bit slower for the same voltage, so my guess is they are all the same winds.

If you want speed just volt it up, though in a 16" you would probably need to go with 150 volts maybe ? that's a lot of juice, that's more than the mains voltage in North America! lol

So maybe cromotor is what you want, but you got to dump more current into it for the same torque I believe ? more than the pie!

Wouldn't a geared Pie be fun ?

I need a good dual suspension bike,

 

[o00scorpion00o]

^--- i fully agree with you

I did actually find a hill worthy of testing just yesterday when i was driving up the mountain.

This is the steepest thing i have found thus far
Most people are going up this hill at about 20-25mph, so i should be going at the speed of cars.

This is my test hill now. There is also a ~10 mile version of this nearby, but i'm not sure if it's paved or not. I will investigate.

Honestly on the trek frame, i've been too nervous to take it up any hills. Just too damn squirrely. Been hunting down proper DS frames for months now. That has been a big hold up in taking this project further. The NEXT bike solves a lot of problems.

Are there any threads on folks installing temp sensors you've read lately? i'd like to see. You're right. I should have a sensor. And i should beef up the phase wires at the windings rather than the axle as well. Already had the motor apart once by now.

I haven't seen threads where someone has installed a temp sensor lately, but cell-man is sending me a new stator to test with temp sensor, along with a new axle, bigger phase wires that come through the bearing, so it should work perfectly with the new cycle analyst!

I think every motor should come with a temp sensor!

Installing one in the pie wouldn't be that hard but I strongly recommend it, motors are not cheap, especially shipped and at least you can sell it on when you are bored with it if you have not baked it by then!

What grade of hill is that by the way ? it looks steep! You need to get testing Dave!

 

[zombiess]

So maybe cromotor is what you want, but you got to dump more current into it for the same torque I believe ? more than the pie!

Wouldn't a geared Pie be fun ?

I need a good dual suspension bike,

I don't know how much torque the pie makes, but both the ebikes.ca simulator an my own simulation using SWBlutos predicts that I'm making 350 N-m / 258 ft-lbs of torque at 0 rpm at 125V 100A into the motor with a 20.2" wheel. It jumps to about 480 N-m at 125V /355 ft lbs at 200A (why I'm trying to get a longer swing arm).

Would be really nice to get a magic pie in either simulator as I'd like to play around with the numbers. I'm quite interested in the controller less magic pie especially if it comes in a higher speed wind and I have some money to play with. I'm just curious and like to experiment and compare. Yes I'm the Greyborg USA dealer, but I love to play around and also help out new people looking to get the most bang for their buck. Not everyone can afford the more expensive monster motors or needs them.

A magic pie sized geared motor would be insane if it works. I don't know much about the gears setups but if something like that were doable it could be great. With the size of the pie you could also run bigger stronger gears and probably go to a helical cut to make them quieter too.

Once you go dual suspension and have good geometry, you'll probably never want to go back to a hard tail because 40mph full suspension is sooooo nice.

Really wish there were ebike guys here in Vegas. I want to ride with someone else.