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

[o00scorpion00o]

Bump Dave!

Any updates ?

[Lemlux]

Electra Fatti-O 20" tires are rated at up to 300# load at 50 psi per customer service. The tire has recently been discontinued in this size, but Cambria bikes says they offer it. Accordingly, I'd hurry if you don't want to settle for the 2.35 BMX tires or go motor scooter tires/rims.

http://www.cambriabike.com/shopexd.asp?Item=100010636

For a 20" rear wheel I'm about to pull the trigger on a 130mm BCD crank with choice of 145, 150, or 155mm crankarms for $47.97, and a 60t 130 mm Vuelta sprocket on sale priced at $21. The 60t sprocket will probably restrict the purchaser to a single crank gear unless they are consderably more creative at derailleur mounting than most.

This crank/crankarm/sprocket combo should greatly assist both the cruising speed gearing and pedal strike issues.

http://www.calhouncycle.com/productcart ... oduct=2619

http://www.vueltausa.com/components/cha ... 8-60t.html

[Lemlux]

The Subrosa Grave Digger tire is called a 20 x 2.30 but measures out at 2.52" wide and 20.9" diameter according to

http://www.danscomp.com/products/442008 ... _Tire.html

(This site seemed to have more bmx tires than any other I've found)

It also weighs considerably more than most bmx tires at 29.4 oz. This hopefully bodes well for tire life with a high torque motor, and it's half the weight of a DOT tire. I imagine that may be as good as it gets for a 20" bike tire if the fatti-O can't be sourced.

[neptronix]

What up yall!!

The build is coming along slowly but surely. Thinking strongly about just getting a cromotor at this point, no better way to ensure i'll have good thermal headroom, hehe..

Apparently Pike's peak & the roads leading to it are closed to bicycles, so i can basically forget test riding out here.. this town is extremely bicycle unfriendly, to a fault

The facebook page for the assault on the peak hasn't been updated since Sep 2. and my comments of wondering when it's gonna happen this year have been deleted.. and the web site is looking dead.
http://www.ridepikespeak.com/

http://303cycling.com/2010-Assault-on-the-Pikes-Peak-hill-climb

..but the link to the original article is gone of course..



Oh well, i'll still have a rad eBike if this falls through

[neptronix]

And for the progress..

The origin8 140mm cranks came in, and have cured the pedal strike issue. But they are on the flimsy side for sure

The 18FET has been mounted, using some hardware store goodness.

Switched the handlebars over to BMX stuff.. the more weight on the front, the better.. and i feel better about leaning into them!

Cycle analyst is all set up, now i realize what i've been missing out on

The half-twist throttle from cell_man is much improved - larger throttle motion range, and i was able to eliminate the handrest bar.

Don't remember if i mentioned this or not, but i managed to jam a 7 speed freewheel on it, using various spacers.

Phase wire connectors upgraded to dual 4mm bullets, since i noticed the housings were getting a little melty!



Gotta finish the precharge unit before i can run 30S though -_-



All coming together.. weather is finally in the 50's and 60's, big improvement from 10-30deg and snowed in . Hopefully i'll have a 30S ride vid tomorrow, if everything goes as planned.

[zombiess]

So if you are on a bicycle you are not allowed to ride up the road the cars drive on?

[Alan B]

You can look at the website for the Peak, as I recall they mention not allowing bikes on the roads. It is a sometimes narrow steep road so I suspect it is a safety issue. So the race is a special opportunity to ride the road.

[JohnC]

@Dave,

Oh, I thought you were talking about the PPI Hill Climb on July 8th, 2012. I kept looking for your name on the scratch sheet wondering what division you would register in. I have not looked at the web site very closely but noticed there is an electric vehicle and motorcycle division. It would be cool if you were the first e-bike to compete. The entry fees are a bit pricey, but maybe you could get sponsors? http://www.usacracing.com/ppihc

[Alan B]

The bike ride up Pikes Peak is later, August it was last year.

[neptronix]

K dudes. The precharge unit is set up, and i managed to jam 30S/10AH into the FalconEV bag. lol.
Top speed is 42mph and i am sagging 5-10 volts on 10AH, so it could be more like 43mph.
Sorry that the cycle analyst and spedometer are hard to see, changing the video quality to 480p or higher helps.



The motor got up to 105F/40C and stayed around there for the duration of the 10 mile ride, including lots of stop and go. This is one stout motor. Being fed ~45mph power for half a mile, my 9C/MXUS motor got so hot that touching it would have almost burned your hand.

When the peak race is over, i'm going to spoke this into a 24" wheel so that i can get a reasonable speed on 20S. 30S is a bit much

[Sacman]

Nice acceleration.

Once you got that 20-inch wheel in the back and 30S I thought that thing was a wheelie machine for sure.
But it looks like you got it dialed down just right.

[chroot]

Hard see your Cyclist Analyst but damn nice hard acceleration look sweet.

[Golden Motor Canada]

Wow, thats some awesome acceleration!

Gary

[neptronix]

Wow, thats some awesome acceleration!

Gary

Have i invalidated my warranty yet, Gary?
May be ordering the big black motor from you soon ^_^

Sorry guys that the CA wasn't too visible. I'll have to shoot at a different point during the day, or put a little hood over it maybe.

The speed is accurate within 1mph VS the bike speedometer. I think i'll just fix up the camera so it can only see the CA from now on.

[gensem]

Neptronix,

Where did you get the long gopro support?

[o00scorpion00o]

Nice one dave!

Isn't it mad how the mac can do 40 on only 16S!

I think the pie is a great motor and good enough for most people. It can take huge amounts of peak power for acceleration. Crazy hills like 16% are a bit much for any motor (a few miles) and not something most of us would be doing daily.

It pulls me up 30% + slopes in the woods, some of them look near vertical I'm putting 80 amps and 120 peak into a 26" wheel, so most of my power is torque, still at 30 mph it's fast enough. I can feel the front wheel lift going up a steep hill.

Dave, you would probably hit 53 mph with 120% throttle ?

I must admit 40 is my absolute limit on a bicycle, you need proper kit even at 40, 50 is a no no for me!

You are more brave than I , or crazier!

[JohnC]

The Dirty Thirty

[Sacman]

Neptronix,

Where did you get the long gopro support?

Looks like a handlebar Accessory "T" Rail for mounting extra stuff on your handle bars.
It's like having an extra 4 inches of handle bar to mount your stuff, only it sits about 4 inches away from your original handle bar.
Kinda like this http://www.google.com/products/catalog? ... sBEPMCMAA#

[neptronix]

Neptronix,

Where did you get the long gopro support?

Sacman is correct

I used a minoura spacegrip.

http://www.amazon.com/Minoura-Spacegrip-2-Handlebar-Computer-Headlight/dp/B0064HLNPO/ref=pd_sbs_sg_6

Not as bad as the reviews suggest ( pain in the ass to adjust it, but if you adjust it right, you won't have problems! ), but there are better grips out there.

I paired that up with an old road bike brake lever, which i drilled a hole through and stuck a bolt into it.
I connected that bolt to the gopro tripod adapter.

http://www.google.com/products/catalog?q=gopro+tripod+mount&um=1&ie=UTF-8&tbm=shop&cid=4061882306429069340&sa=X&ei=sJRdT5S7E-LQ2wWSmcD9Dg&ved=0CH4Q8wIwAQ

The gopro bicycle mount may be better though.

http://www.ems.com/product/index.jsp?productId=4202763&emssrcid=GoogleBase:PS4202763

[neptronix]

scorpion: yeah, the pie is a stupidly low wind. the 8T MAC is kind of a high speed wind. I'd definitely like something that's right in the middle. Coincidentally, the 20" pie is the best motor i could have bought at the time ( no cromotor or Crystalyte 54xx on the horizon when i purchased it ), so for a pike's peak climb at an average of 25mph, it will do

If your front wheel is lifting up, i suggest you move your seat and handlebars forward as much as possible like i did. Remember how icecube57 crashed? unexpected power wheelie after the back wheel caught a bit of air.
At a peak of around 7kW ( much lower when cruising ), this bad boy has the potential to do the same thing.. so leaning on the front gives a good margin of safety.

I agree that 40mph is a bit too much. With no bike lanes out here though, it's nice to have that power, to keep up with cars and such. But i think this will ultimately lead to a motorcycle or car build later on.

I feel like it could be reliable at 40mph on the flats though, with some cooling modifications just to be safe. Perhaps i will rip it apart soon.

[JohnC]

Dave,
Thanks for turning us on to the Magic Pie. What power rating is your MP II? I see three MPs on the golden motor’s web site. I see a 1kw, 1.5kw and 2-3kw. Do you think the latter compares to coveted cromotor at half the price?

http://www.goldenmotor.com/

[o00scorpion00o]

the magic pie III internal controller is rated from 24-59 volts max hot off the charger. And 40 amps

The pie 2 external controller can take a lot of peak power for acceleration and hill climbing.

The cro motor can take more power continuously, so more power for hill climbing. Its also a faster wind than the pie, the pie is more than good enough for the average bicycle. The cromotor is also 2kg or so heavier.

major hills continuously over 2kw could be a problem. You need to monitor temps

[gensem]

John i think the MP is rated for under 1kw (but it can take alot more).

http://www.goldenmotor.com/magicpie/fea ... icpie.html

Its much taller but the magnet are thinner than a cromotor, I ll get one in a 24" wheel just to compare with a cromotor using the same controller and batteries. Im almost sure the aceleration ll be much slower.

[neptronix]

There is only one magic pie motor, and it's rated for "250W-1000W". It appears to come in only one wind, so the smaller wheels require lots of voltage. It does approx. 18mph on 36v on a 26" wheel. The MP3 handles the same amount of power as the MP2, but the internal controller is different.

gensem: Aw man, don't bother, it won't compare. At ~7kW peak, i am definitely getting close to, or touching the saturation point, i can just feel it, since the acceleration wasn't much better than the 4kW i was putting in previously. The cromotor hubzilla has so much more magnet, even though it's not as tall. I'm certain it will handle 15-20kW peaks before starting to saturate, and a kilowatt or two more continuous!

What i'm really excited about is the cromotor deep dish. 22% more magnet, but same diameter, maybe a bit taller. The only downer is the price.. around $500.. but.. i think it will whoop the crystalyte 53xx, at a much lower weight, and maybe even with better heat dissipation.

[gensem]

I think you are talking about the very tall motor there is still going to be released by the croatian crew... hella nice motor, but I can tell you it wont acelerate faster than the fat cromotor.
Im really hoping that Hal pull the trigger on something with 50-60mm magnet and taller than a pie.