HS3570 Hotrod Project with 46T->74T Hammerschmidt Chainwheel

crossbreak

crossbreak

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Joined
Aug 2, 2011
Messages
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Location
Germany
Former Project Name: MagicPie2 20" Hotrod Project with 52T Hammerschmidt


Hi folks,

inspired by izeman http://endless-sphere.com/forums/viewtopic.php?f=3&t=38848 I want to start my own conversion.

from izeman's thread
quote
I'll also order some JB-Weld. I like your long swing arm, but I can't build such a thing. Now I will elongate mine with 4x 5mm thick AL-7075 sheets on both sides, which will be fastened on the original swing arm with JB-Weld. I change my motor for a cheaper MagicPie2 in a casted 20"rim and use the HS3540 on a different bike. Hope the MagicPie2 can stand the 40amps@24s lipo I wanna use :D

GMHubMotorAD.jpg



Thx for your tips about tires, they are so cheap! Hope they fit the 20" MagicPie2 rim properly :? http://www.ebay.de/itm/300856503835?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

I will use 24" front, hope it will look different than neptronix bike ;)
http://endless-sphere.com/forums/viewtopic.php?f=6&t=35060&start=50#p514219
peakpower.jpg


Also got a Hammerschmidt drive on the bay that will be fitted so I can still pedal at 45mph :twisted:
/quote


Big Hubmotors do a great job in a small rim. The largest i found that is relatively lightweight is the MagicPie2, it is 300mm in diameter.

Drawback1: Need a huge overdrive from the pedals to the wheel
Solution: Hammerschmidt drive gives a factor 1.6 extra overdrive. 52T chainwheel and 32-11T sprocket cassette means 52/11x1.6=7.56 overdrive ratio, or 60kph @ lazy 80rpm crank rpm, with a 20" wheel.
Problem: Hammerschmidt drive comes with 24T chainwheel max, solution: Make an adapter from 7075 alloy


Drawback2: MagicPie has only 7.4KV :( http://endless-sphere.com/forums/viewtopic.php?f=30&t=34750&start=75#p516494
Solution: Terminate it in Delta, so it has 7.4*1,73=12.8KV :D

I want to use a 26" MTB frame, since it has nice suspension, I ride this bike since 3 years, first with turnigy 80-100 middrive, then with 250W tongxin coinverted to middrive with derailleur, then with 9-speed SRAM internal geared shifter Hub, then with Goldenmotor MBG geared hub, then with Clyte HS3540, all in a 26" rim.

I'm fed up with 26", too lazy to respoke my HS3540, now I go for a MagicPie2 in a casted 20" rim.

Drawback: The rim isn't very stiff since it's made from alloy 6000
Solution: Stiffen the rim by adding alloy pipes, fastened with JB-Weld, and use fat 16-2.5 moped tires
Drawback: Looks ugly
Solution: Make it a slice wheel, like the ones used in a race bicycle

Hotrod
Controller: 18s Lipo, 24Fet IRFB3077, 85amps sounds much for this motor, but in Delta the current gets divided by two. The max phase amps is set to 115amps, so each winding sees only 57.5amps maximum. That should be ok if properly cooled and monitored by the Cycla Analyst.

Cooling: Drilling holes into a hub is very common these days. I will coat the stator with brake caliper paint to make it waterproof

BIG PROBLEM:
I thought that MP2 has an external controller, mine has an internal controller :x did I get the MP3 or what is wrong here?!?!
 
thx spinningmagnets!

the other side:
DSC_0033.jpg
DSC_0034.jpg
here we can see where the star point is located: Just separate them
View attachment 3
Done! Now we have to figure out which ends to connect. We connect one of the unmarked with one marked....then there is only a 50%/50% chance to connect the other two the wrong way and blow our controller...wait there once was the lebowski method!


Lebowski said:
ok, the clue is to connect everything in a triangle.

Take one winding (lets call this one 1), this is your reference. Spin motor (drill press ?) and measure AC voltage accross this
winding using normal multimeter (in the AC setting !!!!).

Take another winding (2 ?) and connect it to the first one in series. Measure the total series AC voltage. I know it sounds a bit
strange but the total series AC voltage should be equal to the AC voltage of a single winding. If you measure around 1.7 times the
voltage of a single winding then reverse the connections of winding 2 to end up with an AC voltage equal to that of a single winding.

Now connect the third winding (3) in series with 1 and 2 and measure the AC voltage again. If you measure 2 times the voltage
of a single winding, reverse the connections of winding 3. If the total AC voltage of the three series connected windings is 0 then
you've connected everything in the correct order. You can now short the start of winding 1 with the end of winding 3 (remember,
the voltage was 0 so this is no problem).

Now you got your 3 windings connected in delta.
Click to expand...
 

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I just recognized the motor has 56poles :D thats a lot!

If a MAC motor with 32 poles (0.5mm laminations) runs into eddy current loss at 1000rpm, this motor should run into eddy current loss at 570rpm if it has also 0.5mm laminations :x

that is only about 55km/h :shock:


on the other side, a MAC runs into eddy current loss at 1000rpm/5=200rpm, which is 19.2km/h in a 20" rim :x
 
crossbreak,

i'm following your build thread and like to see the pie getting converted to delta.

if you don`t need the internal controller board anymore, i would be interested in buying it,
as you need money for your fourth bike :mrgreen:

cheers, phil.
 
Hey.. my bike didn't turn out like that! ;)

wheeldifference.jpg


This was the end product; 24" wheel on the right, 26" on the left.

You will want 145mm cranks or smaller. You want the front of the bike to be as low as possible. I don't know if this will be a wheelie machine for you with a different winding - however, just beware of all the problems i had running a 20" wheel out back.
 
Since I need some parts for the 20" wheel, like a valve adapter. The valve wont fit due to low distance between hib and rim :shock:

Now I'm thinking about fitting the hammerschmidt to the 26" and just solder the HS3540 in WYE/STAR to make it a "HS3570" and go 70km/h :D

the width of the MagicPie has not convinced me. I'm back on the Idea to stay below 60V and use 12s. It's saver
 
This was the end product; 24" wheel
Click to expand...

this is so nice, i did not see that.

My 20" is acutally 21.5" and my 24" is actually 24" !

One day I'll use that setup, I just need a bike :D Got a front and back wheel with discs, brakes and controller :?
 
My rear tire was larger. I had a 2.75" moped tire so wide that i had to cut the vbrake bosses off.

I have ran a Crystalyte HS3548 in a 20" wheel and a magic pie in a 20" wheel. The motors are very close in terms of the power they produce, but i found the magic pie to be more efficient for whatever reason ( maybe there was something wrong with my HS3548.... ) I'll tell you right now that the heat shedding capabilities of the magic pie are better.

Had a real hard time keeping the front end of my race bike down with the magic pie. I had to tune the power down a lot. To keep the front end down, i was running ~6500W peaks through it.

If you are going to run the HS3540, run it in the tallest 20" tire your frame can tolerate. Keep the winding the way it is. Feed it 72 volts and a minimum of 50A and it will be an effin' rocket.

By the way, regen in a 20" wheel is very strong. Especially in a torque winding. You'll not need a disc brake out back at all, unless you need the modulation ability that a mechanical brake provides, like if you are going off road etc.

Oh one last thing ( sorry to lecture you :lol: ) but a 60T front chainring to a 11T gear will allow you to pedal even up to the high 30mph figures on this size wheel. You may not need the hammerschmidt thingy. Once you get up to crazy power levels, you will find yourself not needing many gear ratios anyway :mrgreen:
 
The Hammerschmidt is a 2-speed gearbox. I have thought about going for 2-speed. 60/11 is too slow. I need the hammerschmidt even on my 26" I will go for 52/13.I use 9-speed SRAM since years. honestly I dont want something else.

Running more than 60V is actually not am option due legal issues. I want to stay with 12s, already inserted better AWG10 phase wires, so I can use a 85amps max controller. 45V*85amps is also almost 4000Watts. Maybe I change it for 120amps some time. Hope my 24xIRFB3077 can stand this.

This will definitely be a wheelie machine :D I want to use my self coded adruino throttle unit to keep the wheel down. It tries to make a flat torque curve, so I should see the same torque from a dead stop to around 30km/h.
 
da liegst du falsch ösi :D

*sry :mrgreen:


250w CONTINUOUS motor power , 25kph, 6kph throttle only

(Das ist ja die Mogelpackung die ein Pedelec überhaupt erst fahrbar macht. Limitier mal dein CA auf 250w und genieß die Anfahrpower :p
BionX wurde schon mit 800w gemessen.(was auch im Vergleich gut hin kommt)

Und in DE gibts glaub ich eine Maximal DC Grenze von 60v für den Laien/Hausgebrauch. Darüber muss man glaub ich "offiziell" Fachmann sein. Vermutlich auch einer der Gründe warum es kein Pedelec/Ebike über 60v gibt.

...hatte grad keine lust auf englisch :p
 
The 120V DC limit is defined internationally as small voltage. Both insulation and ground traces can be made much more simple than for systems that exceed this.

Due the fact that ebike motors are driven with AC, the maximum Volatge may not exceed 50V. The 60V figure is not quite accurate. http://en.wikipedia.org/wiki/Extra-low_voltage
 
I don't know how they technically define 3 phase power in germany, but i think what comes out of the controller is technically DC.

Anyhow, aren't you building something illegal already?
 
maybe you will be interested in this experience with mag wheel MagicPie
it did not last long for that owner.

http://endless-sphere.com/forums/viewtopic.php?f=4&t=39594&p=738623&hilit=+Magic+Pie+mag#p738623
 
thx for that link! i already read that. my opinion is also that the five 'spokes' are placed too far from each other. I'll add five more spokes and glue them with strong JB-Weld Epoxy. I additionally use a strong moped tire.
 
That broke due to a heavy impact with a "stone border" ( i assume this means curb ), not just during ordinary riding. I smacked potholes at >40mph with my 20" magic pie and i had no suspension plus i am 250lbs.

You are going to have a larger tire than he did.

I wouldn't worry about it at all.
 
thx! Still i'm playing with numbers :? Made a new thread about high speed pedaling and overdrives here:

High speed pedaling: Comparing MEGA-Overdrives - BIG LIST http://endless-sphere.com/forums/viewtopic.php?f=3&t=50299&p=744360#p744360

Think I will finally go for
#2: Hammerschmidt chain wheel adapter and 11-32T derailleur
Overdrive: 1.6
Smallest sprocket: 11T
Over all overdrive: 52/11 x 1.6 = 7.56

Spread: 465 %

Speeds at 85rpm crank speed: 26"->80km/h, 21.5"->66km/h
Speeds at 85rpm crank speed: 26"->50mph 21.5"->41mph

With 52/13 this would still be 68km/h or 42mph for the 26" tire. 13T sprockets are much better since 11T eat chains :evil: If I solder my HS3540 in Delta, I could do what I planed on the MagicPie. But I would not run into the eddy current losses that the MP has above 55km/h :x
 
45V/85amps on a HS3540 in Delta is like 77V/50amps in WYE.

So I compare the 21.5" with 26" tires, the difference in efficiency isn't that great :?

But: The 21.5" overheats after 29 minutes, the 26" after only 7 :shock:

Edit: There is also the difference that 26" runs 70km/h, the 21.5" only 64km/h
 

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I ask myself if a 2,25 x 19"moped tire fits a 26" wheel? has someone tried that?

Edit: After calling some tire suppliers I found that it wont fit. the only moped tyre available here, that fits a 26" rim I found is the Conti KKS-10 22-2. It has the same price as quality bycicle tires so i will try them. Sad that it's made for 50km/h and 95kg max :x still better than a bycicle tire I hope

Conti KKS10 homepage:
German: http://www.conti-online.com/generator/www/de/de/continental/motorrad/themen/rollerreifen/moped/kks10/kks_10_de.html
English: http://www.conti-bike.co.uk/default.asp?spid=15
 
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