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Allen_okc
24 March 2011, 1144
hello everyone - i was reading this thread (http://www.elmoto.net/showthread.php?752-LIPO-Batteries&highlight=lipo+batteries) , i very new to lithium batteries, so please forgive...

but im building a drag scooter - 48 volt 300 amp 19 hp, i have links below to best describe the components im using...

its basically a bicycle type little drag scooter, custom built by me...

my question is the batteries - this is a link to the batteries i think i need;

http://www.electricmotorsport.com/store/ems_ev_parts_batteries_lpf_gbs_20ah.php

the problem is im not sure about the batteries i need - the lead batteries would be fine but i need to lose some weight on the bike, and lithium bats would be a big improvement...

im not sure how many or what type i need - can anyone help?

motor controller - please dont laugh...
http://kellycontroller.com/kd4840024-48v400aseries-p-226.html

the motor...
http://www.electricmotorsport.com/store/ems_ev_parts_motors_me0709.php

this is the scooter which im welding on to improve the wheel situation...

943943944

Nuts & Volts
24 March 2011, 1221
Moved post to a new thread, hope you dont mind :)

I dont think those GBS 20Ah cells will give you 300A. I have seen the 60Ah cells do over 350A I think. Personally I have 24 60Ah cells with a Kelly 400A brushed controller and have only ever seen 180A battery side. So you may want to go up to the 500A kelly controller.

I would either recommend the Turnigy Nanotech LiPo, a high C rate Lipo (30C+), or 8Ah Headways (here. (http://www.manzanitamicro.com/products?page=shop.product_details&flypage=flypage.tpl&product_id=61&category_id=29). You could build a small 16s2p pack of those Headways and have about 48V and 320A+. I think all three will come in at about the same price.

Maybe if you run 5Ah nanotech you may have 1 extra series battery to factor in some voltage drop, maybe. You could also run 1p with those cells, so your pack contruction and charging would not be as complicated. Weight would be the lowest too.

The amount of cells and thus your pack price, weight, energy, and volume will depends upon your runtime, # of runs before recharging, and the actually distance. So if you answers those questions we can help out some more.

larryrose11
24 March 2011, 1413
I would agree with N&V. 500A kelly. For high power / light wt application, LiPO is the way to go. the cells you linked to are rated for 3C, that means:
C rating * cell amp-hr rating = rated current.
3* 20 = 60 Amps = sad racer
Pulse curret is less than 1 sec usually.

The higher c rating of your battery means that the cell voltage wont sag as much under race load = higher power delivered.

EVcycle
24 March 2011, 1554
Welcome Allen! Nice setup!

I recommended Allen to this site. He has been working on this project for a while.

@ Allen: These are the folks that will help you get to your racing goal! (and no BS to speak of!!) :) :)


Ed

Allen_okc
25 March 2011, 0824
Welcome Allen! Nice setup!

I recommended Allen to this site. He has been working on this project for a while.

@ Allen: These are the folks that will help you get to your racing goal! (and no BS to speak of!!) :) :)


Ed

Thank You Ed - you have been the greatest help to me... i can really tell that the group here are sincere and very knowledgable about EV racing... this is something ive dream of doing for years, and at 54 years old i want to do this project badly, and i have sacrificed a lot to get this far, going without lunches dinners going out etc. just to have the time and money to build this money pit... but im like a pit bull, i cant let go till its running down the drag strip...

i just need to get a grasp of the lithium batteries, like its been said before " I over think a problem to much "

Anyway the tubing came in yesterday so i can start rebuilding and modifying the hard tail to fit the new wheel and motor, hoping to have it all assembled by mid week, then i have to start collecting batteries, piece at a time, but i need to know what type and how many... the 08AH 38120 P Cell looks promising... Thank You Fellows...

EVcycle
25 March 2011, 1547
Photos! We need photos!!!!

Allen_okc
28 March 2011, 0751
these are photo taken today of the new hard tail construction... with the new michelin tire on the way...

948949950951

Allen_okc
28 March 2011, 0759
I get to cut the old hard tail off today and prep the frame for the new hard tail... everything should fit properly with this new refit...

Allen_okc
28 March 2011, 1052
hard tail removed...

EVcycle
28 March 2011, 1104
Very cool. It looked weird with that other tire on it anyway. :)

Allen_okc
28 March 2011, 1207
it kinda looked like some type of mud slinger... now theres a thought...:rolleyes:

Allen_okc
05 April 2011, 1115
hardtail welded on, still waiting for the tire to come in, which it got shipped out yesterday, after two weeks, be here friday - S rated tire...

i just need to order the front and rear sprocket and chain before i can weld down the motor mount...

still trying to decide on what battery pack to go with...

EVcycle
05 April 2011, 1607
Very well done.

You have been busy! How much clearance will you have?

Allen_okc
08 April 2011, 0556
with the new tire it will have four inch clearance, it sets pretty low now, it almost looks like a rocket sled...

after i get the tire mounted i'll take a picture of it...

im also gonna order these batteries today... this was a hard decision, since i know so little about the lithium battery, but i need to learn and best way is to have some and see what they can do...

http://www.manzanitamicro.com/products?page=shop.product_details&flypage=flypage.tpl&product_id=61&category_id=29&vmcchk=1

Allen_okc
11 April 2011, 0957
the frame is set up for the motorcycle wheel and the larger motor...

gears and chain are on the way and the first four lithium batteries from Manzanita's...

http://www.manzanitamicro.com/products?page=shop.product_details&flypage=flypage.tpl&product_id=61&category_id=29&vmcchk=1

only 12 more batteries to go, then the hardware needed to maintain them...

the tire is S rated and mounted...

DaveAK
11 April 2011, 1002
Looking good Allen!!

frodus
11 April 2011, 1006
im also gonna order these batteries today... this was a hard decision, since i know so little about the lithium battery, but i need to learn and best way is to have some and see what they can do...

http://www.manzanitamicro.com/products?page=shop.product_details&flypage=flypage.tpl&product_id=61&category_id=29&vmcchk=1

I'll help ya, I work for them, and specialize in Headways (I have 200 of my own).

What kind of pack are you building? How many cells? Peak discharge? volts?

Let me know

EVcycle
12 April 2011, 0215
Looks much better with that wheel/tire combo. The bike sits nice and level. It should be a fun ride!

Allen_okc
13 April 2011, 1030
I'll help ya, I work for them, and specialize in Headways (I have 200 of my own).

What kind of pack are you building? How many cells? Peak discharge? volts?

Let me know

sorry i havent been around in a while - im chewing fingernails right now...

Ed is helping me with a layout - but in answer to your question, im going with 32 of cells which should produce 400 amps, but i will be testing with 16 cells to make sure everything is wired right at 200 amps...

its my first time using lithiums so im gonna be on the edge with them, very very careful like... but if you hear the fire department running to my house you'll know what happened...

Allen_okc
13 April 2011, 1032
i was just curious - has anyone had any problems with electric motor sport? i orderd a sprocket and chain last friday and i havent heard a word from them since...

frodus
13 April 2011, 1042
they don't make them, they order them from sprocket specialists, so it will take a week or two.

Allen_okc
13 April 2011, 1045
Thank You frodus...

I need to mention one other thing - the folks there at Manzanita are the greatest, very helpful and understanding...

praises to Manzanita and you frotus... Thank You...

Skeezmour
13 April 2011, 1047
Thank You frodus...

I need to mention one other thing - the folks there at Manzanita are the greatest, very helpful and understanding...

praises to Manzanita and you frotus... Thank You...

Like most people on this site we really care and want to see good projects on the road or track.

DaveAK
13 April 2011, 1047
Looking forward to seeing this thing running!

Allen_okc
15 April 2011, 0730
well i got my first four lipo4 batteries, if it wasn't for my girlfriend or the fact that the batteries can be dangerous, i would have slept with them last night. was that too loud...:p kinky

anyway i ordered eight more today - i figured if i order them every week i should have have the full 32 cell set soon/later...

i have a question about the regulators, i have one option, use individual chargers without a BMS or use the regulators - my question is, with the regulators can i use a regular 12 volt battery charger with the MK3x4SMT Digital Lithium Regulator?

http://www.manzanitamicro.com/products?page=shop.browse&category_id=22

Oh Yes one other thing - im going to line the battery tray with rubber tuff coat...

Allen_okc
26 April 2011, 0917
a new update - im now at 12 lipo4 batteries - four more to go and two 3X8 regulators.

i do have the chain and motor sprocket "pinion gear" finally, which now i can weld the motor mount to the frame, and that finishes the drive train...

with four lipo4 to go i can start doing the road testing and motor break in - i collect the full 32 lipo4's then i can start racing... getting closer...

Allen_okc
28 April 2011, 1003
everyone has talked about what not to do with lithium batteries - what do you do if one does explode, will a fire extinguisher put the fire out before the others blow, or is the cycle just doomed?

frodus
28 April 2011, 1008
they shouldn't explode. Liveforphysics did a test and had to torch it to get it to do anything. He overcharged, overdischarged, heated it up, and nothing. Finally took a torch to it. I think they just kinda smoulder. metal cased batteries seem to hold up pretty well. Its the plastic holders that I'd be concerned with, so get something that'l put out a fire of burning plastic.

Allen_okc
28 April 2011, 1136
Thank You frodus - i seen the same video, very interesting. i feel safe with your batteries, but there's always those moments when it could happen, per say if the bike wiped out in a crash...

http://www.youtube.com/watch?v=dree0rTr1HM&oref=http%3A%2F%2Fwww.elmoto.net%2Fshowthread.php% 3F1080-Drag-Scooter-Build%2Fpage3&has_verified=1

Allen_okc
02 May 2011, 0520
havent got much completed due to the monthly bills, but i'll pick it back up this friday...

but here is what it is for now...

Allen_okc
04 May 2011, 0506
im so ready for racing, gettin closer...

EVcycle
04 May 2011, 0532
Very cool!

Be safe!!!! ( and no burnouts in the house!!!)

http://juiceddragracing.com/burnout.jpg

Allen_okc
04 May 2011, 0557
gee Ed - i hope that isn't your doing, but it does look like fun!

EVcycle
04 May 2011, 0601
Nope,
I do not have a living room that big!!! :):)

Allen_okc
04 May 2011, 0821
i bet who evers living room it is - could use some air fresher...

Skeezmour
04 May 2011, 0929
im so ready for racing, gettin closer...

Thats looking AWESOME! I do say I'm really drawn to that one sticker on your scooter ;)

ZoomSmith
04 May 2011, 0953
Allen, just curious about why you call it a drag "Scooter"? Looks like an awesome motorcycle to me.

Allen_okc
04 May 2011, 1106
well in answer to skeezmour - it was a most difficult decision on which way to go with the batteries, but you and your staff straight up showed me the way, along with Ed... im honored to display the sticker and all i want is you folks to grow and prosper...

why a scooter, well it started as a scooter project and i've been afraid to call it anything else since. its not fully a motorcycle and not fully a bicycle... its more like a agnus with a lot less power... but im hoping with its small size and large components it will impress the folks here in Oklahoma and get them started in EV's...

Allen_okc
05 May 2011, 0600
Some Good News - i've contacted NEDRA - John Metric, "Gulf Region Director in Texas" and also Mike Willmon, NEDRA President has very nice words about my drag bike and claim i will be the first to help establish NEDRA Nationals here in Oklahoma, which is a big honor for me... just to let everyone know.

im scheduling to race this june, really looking forward to it, "video's included from the helmet cam and external cameras"...

And a Big Thank You to the fellows here in el moto that is helping to make this possible... Allen

Allen_okc
12 May 2011, 0509
this is to demonstrate how light the scooter is with everything mounted including 12 lipos... remember this bike is driven by a EMC-RT (ME0709) 19 Hp Brush-Type PM DC mars motor and a kelly KD48400,24-48V,400A,Series controller...

http://kellycontroller.com/kd4840024-48v400aseries-p-226.html

it will have 32 headway 08AH 38120 P Cells

so how fast do you think it will go???

Allen_okc
12 May 2011, 0717
im hoping to introduce my scooter here...

frodus
12 May 2011, 0819
LiFePo4, not lipo. Headways are LiFePo4. Turnigy, Kokam, etc are Lithium Polymer. There's a difference in chemistry and their nominal voltage.

How fast it'l go depends on gearing, but it should scoot pretty good.

Allen_okc
16 May 2011, 1030
Sorry about all that - the discussion is about the 48 volt battery pack configuration...

frodus
16 May 2011, 1049
ok, cool, just a bit hard to follow with two projects and questions mixed between the two of them

Can you change the setup at all?

Allen_okc
16 May 2011, 1103
Yes Sir i can - it can be changed easily...

frodus
16 May 2011, 1122
can you make it in a 8 cell by 4 cell box? I think that'd make it much easier. It's actually how I have one of mine set up now. Allows you to use 4-hole bussbars. For this, i'd double up on the bussbars that headway sells, for more current capacity.

Allen_okc
16 May 2011, 1138
can you make it in a 8 cell by 4 cell box? I think that'd make it much easier. It's actually how I have one of mine set up now. Allows you to use 4-hole bussbars. For this, i'd double up on the bussbars that headway sells, for more current capacity.

i wish i could, the frame originally was built for lead batteries 6 1/8" wide and the frame is 6 1/4" between the tubes of the frame, i would need 6 1/2" wide from between the frame tubes to lay four beside each other...

if i would have started with the proper batteries, i could have created the frame wider...

at most i can fit 10 cells in one row stacked four rows high - my battery box is right now, 17 inches long X 6 1/8" wide X 5 inches deep... a new battery pan will need to be built deeper.

but the frame is another issue that will keep me from making a wider battery box, but i can go deeper...

frodus
16 May 2011, 1152
6" is fine if you lay them horizontally. If you're looking at a pack, and the batteries are horizontal, make a pack that is 8 long and 4 tall.

Allen_okc
16 May 2011, 1222
6" is fine if you lay them horizontally. If you're looking at a pack, and the batteries are horizontal, make a pack that is 8 long and 4 tall.

if i did it that way - it would give the room i need for the regulators...

Allen_okc
18 May 2011, 0547
i need to apologize to everyone and do a confession...

like right now im at work, i have two computer monitors - one facing away from my office door and the other at an angle so the salesmen here can see when they walk up to my desk...

the monitor facing away from the door always has the el moto site running on it with photo paint software ready to go up when someone walks in... the other monitor always running corel draw, the software i should be always working on...

so basically anytime i make a comment or ask a question i risk being caught by the salesmen and the boss, when i should be working...

so please forgive me if my questions and comments seem like information left out and like it was done in rush of typing...

So I Apologize To You All - so just slapps me up side the head when my questions seem unfounded and incomplete, maybe it willz wakes me ups... Thank You - Allen...

teddillard
18 May 2011, 0559
so basically anytime i make a comment or ask a question i risk being caught by the salesmen and the boss, when i should be working...

so please forgive me if my questions and comments seem like information left out and like it was done in rush of typing...

So I Apologize To You All - so just slapps me up side the head when my questions seem unfounded and incomplete, maybe it willz wakes me ups... Thank You - Allen...

Not at all. How about I slapz your BOSS upside the head instead? Or MY boss. Now there's an idea... :D

As far as I know, we're all in the same boat, 'cept for those college kids like TDC, who should be slapped just out of general principles... I should be slapped for posting while having a bad week, for example.

Allen_okc
18 May 2011, 0609
:D thats funny, i like it...

frodus
18 May 2011, 0856
haha, ALT-TAB, can ya dig it?

Allen_okc
18 May 2011, 0935
thats how i do it - the quick escape... while acting innocent in front of boss..

teddillard
18 May 2011, 0943
thats how i do it - the quick escape... while acting innocent in front of boss..

I act busy, determined and cranky (at the interruption) to make him think I'm actually trying to get something done.

I know, the cranky part seems like a stretch. :D

DaveAK
18 May 2011, 1001
I just try not to snore. That's a dead giveaway.

Allen_okc
18 May 2011, 1006
my day at work...

Allen_okc
20 May 2011, 0805
well good news;

1.) the battery charger is in, Thank You Travis...
2.) the book From Fossils To Flux is in, looks awesome, cant wait to read it tonight, Thank You Ted
3.) eight more lifepo4 batteries delivered and eight more ordered from Manzanita, big Thank You to the fellows at Manzanita - 4 more lifepo4 cells to go and counting...

and as always a big Thank You to the folks here at el moto, Thank You fellows for all your help...

i'll throw in in my old project from years ago, my drag truck modeled after the Ban Dag Bandit... custom fiberglass body and custom paint by me... oh i forgot, i built this truck at Ireland Log Trucking in Myrtle Creek Oregon...

Allen_okc
23 May 2011, 0512
i was hoping someone can display a schematic of how to wire a BMS to the headway cells, like the MK3x8 Digital Lithium Regulator...

i have four cells left to obtain for the 32 cell 48 volt pack which are parallel and series together... i would like to start collecting everything i need to wire them together...

frodus
23 May 2011, 0751
hehehe, RTFM (http://manzanitamicro.com/downloads/category/2-bms1?download=29%3Amk3x8-lithium-regulator-manual)

Allen_okc
23 May 2011, 0914
Bless Your Heart Travis... Thank You...

Skeezmour
23 May 2011, 0952
Allen,

The MK3x8 will come with a 3' wiring harness already made up for the voltage side. All you will need are some really good ring terminals and some kind of loom to protect that bundle from chafing.

Allen_okc
23 May 2011, 1024
Thank You fellows - every bit helps since im getting so close to riding this rocket sled... i cant wait to give it a test ride, its been a long time since the last ride on this project...

the last time i road it it handle quite well, no vibrations or wobble in the steering, unfortunately i used a, and i hate to say it but i used a Unitemotor, 60 volt 1000 watts which was modified by rewinding it with 22gauge polyurethane and nylon coated winding wire, the motor had the power, unfortunately the night before this video, i had a run away motor in my living room, luckily it was on the jack stand.

so the next day, i was going to ride it anyway full throttle. the miracle was it fixed itself and was operational. that evening it blew out the commentator, fried it but good and cracked a mosfet in the controller. but i did get some good rides out of it before she blew...

thus led to a more powerful set up with better equipment - live and learn...

this video is the first run, and i was taking it easy on it, it did about 30mph...

http://www.youtube.com/watch?v=Ry-SpRwhzk8

this video is the day after the run away motor, so i used the kick stand just in case it took off on me, so i could take the wheel off the ground, but it started working again, not sure why...

http://www.youtube.com/watch?v=FpzTexdQmYs

i will say the bike has changed a hundred percent since then...

Allen_okc
24 May 2011, 0955
this is where i will be drag racing the Spaz Attack at... Thunder Valley Raceway in Noble Oklahoma...

http://www.youtube.com/watch?v=g_zrFjTEiMc&feature=related

Allen_okc
26 May 2011, 1038
good news - eight more headway lifepo4 cells came in today, that leaves four more then i can order the regulators...

i ordered eight of the chargers Ed recommended so i can do a individual charging giving me that option too...

i found the perfect case for the regulators that manzanita has, it was used for message centers by optec... we have a big pile of them in the bull pin... they come with a built in fan and vents which fits perfectly under the seat of the drag bike...

frodus
26 May 2011, 1048
Are those working power supplies?

Any 48V, 12V, 24V supplies?

*drool*

DaveAK
26 May 2011, 1122
Are those working power supplies?

Any 48V, 12V, 24V supplies?

*drool*
Yeah. What he said!!!!

EVcycle
26 May 2011, 1157
Ooooooooooooo Baby......

Allen_okc
26 May 2011, 1228
actually there fried, but the cases are good along with the fan, the circuitry has parts that are useable too. but i can fit two MK3X8 regulators into them according to the dimensions in the pdf file i have...

optec doesnt recondition them so we just pile them up in the corner in the dark...

im getting a feeling you fellows want one to play with?

DaveAK
26 May 2011, 1239
im getting a feeling you fellows want one to play with?
They're the same kind of units I used to build my charger. But if they're fried then they're not much use to me. Should make nice cases for you though.

Allen_okc
26 May 2011, 1249
it looks like they vary, but mainly 24 volts... i can find out more about them when galen gets in, he's the service tech for the message centers...

frodus
26 May 2011, 1308
just to let you know, there's good money to be had in selling those over on endless-sphere to the tinkerers that can fix them.

just sayin.....

Allen_okc
26 May 2011, 1312
Thank You Travis, but im just glad we had them for my purpose, but if anyone wants one on this forum, are welcome to them...

Allen_okc
31 May 2011, 0725
New update photos of the drag bike - new front wheel and more...

teddillard
31 May 2011, 0749
Sweet! :D

EVcycle
31 May 2011, 0836
Outstanding! When will it be hitting...oops running at the track again?

Allen_okc
31 May 2011, 1057
i should be sliding, i mean rolling, i mean tumbling, i mean running mid june... :D

Allen_okc
02 June 2011, 0624
i thought this link might be useful to someone - it has various kind of calculators and wiring diagrams...

http://scriptasylum.com/rc_speed/index.html

Allen_okc
23 June 2011, 0831
Gooder News - the last of LiFePo4 cells will be here today - i will be on vacation next week, my plans are to get this bike running and dialed in...

so i'll be back july 5 with photos and video of the test ride, good or bad... so you all have a awesome week and i'll see you the week after next...

LIVE TO RIDE - RIDE TO LIVE...:cool:

Allen_okc
05 July 2011, 0514
IMmmm BAaaaack - very good news, the dam thing runs - hurray!!!

i did a mild test run with videos and photos to tell the story...

controller was set to 20 percent min to 80 percent max throttle... 50 percent being 200 amps...

http://www.youtube.com/watch?v=ZZ2vunIMspc

http://www.youtube.com/watch?v=WRW8Sl8oO1o

Allen_okc
05 July 2011, 0537
Spaz Attack Configuration;


Kelly Controller - KD48400 48volt 400amp - 20 percent min to 80 percent max throttle

LiFePO4 Headway lithium cells - 32 cells 8ah - 2P16S configuration

Mars Motor 19hp 48-96 volt

2 gauge fine wire battery cable

400 amp fuse

#420 chain 12 tooth pinion gear, 48 tooth sprocket

Michelin S rated tire 120/70-14

Pit Bike fairing

hand made frame 13gauge 3/4 inch tubing

top speed???

teddillard
05 July 2011, 0602
CONGRATS! (I see we share taste and style in jeans, judging by the knee shot! :D) I love the tour video too... great stuff, to see the details.

Allen_okc
05 July 2011, 0634
i love my holy jeans, i have to wear nice cloths to work, but on the weekend im all blue jeans with holes in them, i just seem to feel more myself that way...

Allen_okc
05 July 2011, 0727
just to keep you all informed, once again the videos...

http://www.youtube.com/watch?v=ZZ2vunIMspc

http://www.youtube.com/watch?v=WRW8Sl8oO1o

EVcycle
05 July 2011, 1002
i love my holy jeans, i have to wear nice cloths to work, but on the weekend im all blue jeans with holes in them, i just seem to feel more myself that way...



Cooling for those HOT passes?

Allen_okc
05 July 2011, 1029
hello Ed - sorry about not doing the break in like i should, but im going to disconnect the battery pack and drop the chain and let the motor run on a 12 volt battery for 24 hours to seat the brushes... i believe thats what your saying i should do...

i couldnt help it, after all this time i had to see if the dam thing would start and when i was riding it, she felt strong and ready to run. i can only imagine after its broken in, how strong it will be then...

Thank You Ed...

EVcycle
05 July 2011, 1115
Blush Blush.

Yes, the motor brushes AND the batteries need to be conditioned.

Just take it easy on the next 20 runs or so and you should be OK. (If you can wait that long) :):)

Allen_okc
07 July 2011, 0451
i have a question about the precharger on the contactor - its a 1k ohm/10w resistor, i noticed it passes current to the controller even when the vehicle is shut down...

is that going to allow a slow drain on the battery pack?

if so can a switch be added to shut it off. i know it can, but is it worth the trouble?

lugnut
07 July 2011, 0601
i have a question about the precharger on the contactor - its a 1k ohm/10w resistor, i noticed it passes current to the controller even when the vehicle is shut down...

is that going to allow a slow drain on the battery pack?

if so can a switch be added to shut it off. i know it can, but is it worth the trouble?

After the controller is charged, the capacitors inside of it are at the same voltage as your battery, so no current will flow.....HOWEVER.... The controller will have a bleed resistor across the capacitor so that it drains the caps when power is removed. This is done so that an unconnected controller sitting on the shelf will not be "live". Some safety agencies like UL (if it applied here) would require it to drain to a safe voltage level within like 60 seconds.

So the short story is that, yes, there is a low current flowing through the precharge resistor and the internal bleed resistor. There will also be a small current used by the control logic when there is voltage on the caps. I imagine the total is on the order or 10 to 50 milliamps. Just a guess. For a bike driven every day, or several times a week, no problem. But over the course of a month or longer, it could completely drain your battery.

Putting a switch in series with the precharge resistor will work. But if you forget to switch the precharge on and start the bike, the contactor can fuse on. An automatic sequence precharge circuit can be used. Some newer controllers take over this function. The method I like is to use a second contactor in the battery circuit (in the negative line) or a manual disconnect. If the bike is in storage for any length of time, disconnect the battery. Or if you're working on it.

Allen_okc
07 July 2011, 0854
Thank You lugnut - a quick disconnect switch, like the ones used in an semi truck would be a good choice... i should of thought of that before, i used to paint semi's... Thank You again...

http://www.jegs.com/pt/Battery+Cutoff+Switch

frodus
07 July 2011, 0859
that'd work, get the beafiest one you can, since it's not 12V you're working with.

Allen_okc
07 July 2011, 0904
Thank You Travis, and i noticed they aren't cheap either, but ive seen cases with the semi trucks it kept the truck safe when a quick disconnect was needed...

frodus
07 July 2011, 0945
nothing is cheap in EV's..... you're switching a lot of amps.

lugnut
07 July 2011, 1329
nothing is cheap in EV's..... you're switching a lot of amps.

Ten bucks for this ain't bad :-) http://order.waytekwire.com/productdetail2/M50/44075/MASTER%20SWITCH%20WITH%20DETACHABLE/

Allen_okc
07 July 2011, 1333
Thank You lugnut - i still havent seen a 400 amp switch yet... even a blade switch would probably work...

Skeezmour
07 July 2011, 1350
Ten bucks for this ain't bad :-) http://order.waytekwire.com/productdetail2/M50/44075/MASTER%20SWITCH%20WITH%20DETACHABLE/

Those are either 12 or 24 volt rated. You start throwing 2x-4x the voltage at them and when you really need it to work it could flat out just flash over and you get to stand there and watch the fun continue. Just because it can handle 500 amps for some period doesn't mean the contacts will break arc from 72+volts.

lugnut
07 July 2011, 1351
Thank You lugnut - i still havent seen a 400 amp switch yet... even a blade switch would probably work...

I think that it was rated at 100 amps continuous and 500A max. Since you're not using it to make or break under load, voltage should be O.K., within reason. I haven't followed your build carefully, but I imagine it will do the job for you. The other nice thing about this switch is that officials at race tracks will recognize it in case you ever get to a track with your machine. Mount it in the rear where it is visible. If you ever need to break it under load, or if it overheats, it is cheap enough to have a spare on hand and should be easy to replace.

lugnut
07 July 2011, 1358
Those are either 12 or 24 volt rated. You start throwing 2x-4x the voltage at them and when you really need it to work it could flat out just flash over and you get to stand there and watch the fun continue. Just because it can handle 500 amps for some period doesn't mean the contacts will break arc from 72+volts.

It is a safety/service disconnect. Not intended to break (or make) under load. However, if needed to, it is in the battery line between the source and the controller which has caps, so not a very inductive break. I think it would do it at least once :-) And if that happens, he has had another problem causing it to be used in that manner. So while he's fixing the other problem, he can replace his $10 disconnect.

Warren
07 July 2011, 2137
lugnut,

"The method I like is to use a second contactor in the battery circuit (in the negative line) or a manual disconnect."

The Cycle Analyst maker shows a fuse and cutoff switch in the positive line from the battery. This is on an E-bike, but the same idea. Why are you using the negative line?

lugnut
08 July 2011, 0315
lugnut,

"The method I like is to use a second contactor in the battery circuit (in the negative line) or a manual disconnect."

The Cycle Analyst maker shows a fuse and cutoff switch in the positive line from the battery. This is on an E-bike, but the same idea. Why are you using the negative line?

I use a contactor (or manual switch) in the negative battery line. And the contactor with the precharge in the positive line. It provides extra measure of safety in case positive contactor should fail shut. Also, the negative switch disconnects everything from the battery. When it closes, the DC/DC comes on. And then the controller can be precharged around the positive contactor. Depending on the layout, the "negative" switch or contactor could go mid pack or inside the battery box while the positive contactor is near the controller.

I have also done a vehicle with a time delay relay for the precharge circuit. I like to have the controller isolated when the keyswitch is off. There is no one right way; whatever works for you :-)

Allen_okc
08 July 2011, 0608
i think i'll try lugnut's ideal, its reasonably priced and the worst that can happen is it welds itself closed - my contactor controls the positive wire, the negative wire is direct to the controller...

this is a schematic of my wiring system, that was approved by kelly controller...

Allen_okc
08 July 2011, 0617
i thought i would show a pic of my inspiration into the EV world - i custom built this truck in 1995, i made the fiberglass body and hand lettered and painted it - i used an old tamiya suspension from 80's brutus model - the suspensions are pot metal, thats how old it is - i put a nine wind drag motor in it with a speed controller that could handle 24 volts... top speed was 55.2 mph, it was ok for the time...

Allen_okc
11 July 2011, 0726
Hear Ye, Hear Ye - update of my project... cant call it a drag bike anymore, but i can call it an experimental vehicle that will be tested at the drag strip...

the first video, which was mainly of my hand and holy jeans was prior to conditioning the motor - so the bike is back on the jack stand with the wheels off and the battery pack disconnected...

im running the mars motor which has brand new brushes on it, with a 12 volt battery for 24 hours for conditioning the motor...

a new tire for the front wheel will be in this week, along with new brake shoes and bearings... so i entend to ride it again this weekend with a full video coverage to see how it does... i promise more external coverage and still with my holy jeans.

too hot here for black leathers...

Allen_okc
20 July 2011, 0507
this is a comment i made at the foat...

i took the bike to work, where there is a 200 foot long parking lot - i gave it a slight and i mean slight turn of the throttle 1/16 and it took off like no ones business, gave it more throttle and it picked up speed to 30mph, half way through i gave it 3/4 throttle and the bike lunged, then i had to back off and ended up on the lawn before it stopped...

this bike wants to run... i cant wait to take it to thunder valley to see what it will do... im betting it hits at least 60mph... we'll see...

Allen_okc
21 July 2011, 1010
Houston i have a problem - i charge the lifepo4 batteries to top them off, the batteries are fully charged 55.8v, but now the controller flashes the code over voltage error at regeneration...

the code for the KD controller flashes 41

any ideals how to reset it or cure the problem...

i charged it with everything hooked up...

DaveAK
21 July 2011, 1041
Can you dial back or disable the regen setting?

Allen_okc
21 July 2011, 1046
i havent tried anything yet - the manual says;

"the voltage is higher than configured overvoltage value. The controller can resume operation when the voltage lowers and brake cycled".

the cells where charged and the gauge said 58.4 volts, after an hour it said 55.7 volts, so im thinking about disconnecting the pack from the controller and see if that resets it...

but i havent check to see if i can set the over voltage value to a higher setting...

and Thank You Dave - i get panicy when things go wrong...

Allen_okc
21 July 2011, 1307
i tried the scooter again - everything is OK, its working again...

i think i tried to use it before the cells had a chance to settle...

frodus
21 July 2011, 1313
yeah, regen fresh off the charger can be tricky

Warren
23 July 2011, 1712
"There is no one right way; whatever works for you"

Thank you lugnut. Got my Amp connectors and crimper today. Time to start learning by doing. :-)

Allen_okc
02 August 2011, 1040
i have a question...

im doing 38.4 mph in 500 feet with a 12 tooth on the motor and 48 tooth sprocket on the back with a 14 inch tire, which measure 22 inches outer diameter...

if i add a 15 tooth on the motor - how much higher of a speed will i gain???

im asking because, im racing a motorcycle that pulls 8 second quarter miles, but we will racing 500 feet only, i'll lose but it would be very interesting to see how bad - of course it will be on video, next monday...

DaveAK
02 August 2011, 1111
I think it's simply a ratio of the two front sprockets if they're the only thing you're changing, so 15/12*38.4. Someone correct me if I'm wrong.

However, there's a big but in here. If you go for a larger front sprocket you'll reduce your acceleration so you might not hit that new theoretical top speed in 500ft. In fact I'd bet you won't. Over 500ft you might not notice any improvement in top speed. I'm not very good at imagining distances so it would have to be something you test out.

frodus
02 August 2011, 1143
what RPM are you at at 38.4mph?

22inch diameter wheel, 4:1 ratio, that's really low for an etek, I'd actually go higher rear, or smaller front, get those RPM's and torque up and you'll be into the peak power range.

38.4mph is only about 1050RPM. Going higher front is only going to kill your acceleration further, and put you into a low HP band of the motor.

Allen_okc
02 August 2011, 1203
i would like to goto a higher tooth in the rear sprocket, but they are hard to find for a XR75 wheel because of those solid blocks it uses...

http://cgi.ebay.com/ebaymotors/NOS-Honda-XR75-CT70-Rear-Sprocket-402S-36-36T-_W0QQcmdZViewItemQQhashZitem20b31a6f5fQQitemZ14044 3807583QQptZMotorcyclesQ5fPartsQ5fAccessories

so my only hope to gain on the top end is the front gear... the take off torque is really extreme, it launches like it got hit in the rear end by a car... plenty of torque...

this motor will goto the chopper project and the harley davidson wheel has a wider selection for the rear sprockets... but for this test of gasser against ev is monday... and the 15 tooth sprocket is on its way...

what i need to do is get a collection of gears and sprockets to play with... video monday... till then im screwed huh?

Allen_okc
02 August 2011, 1259
this bike does a eight second 1/4 mile...

frodus
02 August 2011, 1306
so my only hope to gain on the top end is the front gear... the take off torque is really extreme, it launches like it got hit in the rear end by a car... plenty of torque...


but it'l be even higher torque with a ratio like 5:1, and because of that, faster acceleration. And since you're way below the RPM that would be given at 48V, you shouldn't hit a limit on speed.......

what year xr75?

have you gone to sprocketspecialists.com?

Allen_okc
02 August 2011, 1322
its a 82 honda xr75... i bought it on ebay... at the time if i knew the gear was like that i would have gotten something else...

but no i havent been to sprocket specialist yet... i'll give it a try...

the good part is this race is just for fun, since we are both curious about what the results will be...

DaveAK
02 August 2011, 1324
I'm curious too! Keep us posted. :D

Allen_okc
02 August 2011, 1329
Thank You Travis - i just saw their list shows 35 to 72 tooth, the year isnt right, maybe its the same but the ct70 is correct...

should i go for the 72 tooth?

Allen_okc
02 August 2011, 1331
you betcha Dave - it will be video coverage from my helmet and external cameras...

i just hope i dont embarrass everyone...

frodus
02 August 2011, 1337
they'll make a sprocket for you, just tell em the year make model and chain pitch. Made me a 60 tooth for my VFR.

72 is a little high, maybe a 60 tooth? but then again, if you can fit a 72, do it, front sprockets are easier to find..... if you use #50 or #40 chain

Allen_okc
02 August 2011, 1356
Thank You Travis...

EVcycle
02 August 2011, 1417
I agree on the 60. 72 will be way to big of a gear and with that lite of a bike, just spin the tire... :):):)

frodus
02 August 2011, 1426
well, yeah, if you kept a 12 tooth and did 72. Just stick near 5:1 or so and I think you should be fine. 70/14, 65/13, 60/12, somewhere in there. Maybe something in between, so you can go up or down a tooth on the front. Just stay clear of 10-11 tooth sprockets if you can. It'l wear out the chain a bit quicker due to the tight radius the chain has to flex around. I've heard of binding with a 10 tooth.

ZoomSmith
02 August 2011, 1644
Be sure to check your swing-arm clearance. You may not have room for anything bigger than a 60 (if that).

frodus
02 August 2011, 1650
Great point! I know mine was close, if I'd have gone higher, I'd have hit the Swing Arm.

dice23
03 August 2011, 0639
allen...just stick with a 50 ish and the 12 front should be the ticket. 70 tooth might be as big as the wheel...lol.

frodus
03 August 2011, 0827
that's only going up 2 teeth from his 48 tooth, not much of a difference. I just think he could get way more torque out of this bike if he had a higher ratio. 50/12 isn't much different than what he's got. He can get into his power band much quicker for his short drag races.

I still say 60 rear, 12 front. Gives him flexibility to go higher in the front to match a 48/12 ratio.

Allen_okc
03 August 2011, 0835
Thank You Fellows - the twelve tooth is about as small as i want to get - the chain is almost touching the bolt edges on the shaft as it is...

i'll definitely get a higher tooth rear sprocket for the rear "60" - but it wont be here in time for this little race - a lot of people around here will be there to watch - they're all very curious to see what happens...

he's got a very powerful kawasaki, which i picked... my thoughts was to pick the baddest bike to run against, figuring if i can stay close on his ass then the rest of them will be a little sceered to run me at 500 feet...

i turned the heat on the controller up to a 100 percent throttle amps, i was running 80 percent... so today in an hour im going to take it out on lunch time to test run it... hoping i can break the 40mph or more in a 500 foot run...

hell i love this stuff, i cant wait to run him good or bad...

Allen_okc
03 August 2011, 1200
well all i got was 38.9 mph in 500 feet - so with that said why not try to learn to burn the rubber???

http://www.youtube.com/watch?v=LBs-rcoGK_c

sorry if the video is a little long, but this was today at lunch...

EVcycle
03 August 2011, 1745
Not too shabby for a first try!

Keep practicing! :) :) :)

Allen_okc
04 August 2011, 0516
no problem on the keep practicing - like you said Ed, its a form of art. it really does take practice...

anyway here is the ride i did yesterday at lunch - 500 feet 38.9mph...


http://www.youtube.com/watch?v=7lyL11EFSYQ

Allen_okc
04 August 2011, 0604
from yesterday...


http://www.youtube.com/watch?v=LBs-rcoGK_c

Allen_okc
05 August 2011, 0703
i notice that the lawless team is running a 19 tooth pinion gear on the motor and a 48 tooth sprocket on the rear, giving a 2:1 ratio... why?

EVcycle
05 August 2011, 0707
i notice that the lawless team is running a 19 tooth pinion gear on the motor and a 48 tooth sprocket on the rear, giving a 2:1 ratio... why?

LOTS of torque! They can get away with it and they need the top end wheel speed.

During the TV shows, I believe they had to go to a steel rear sprocket due to the HP the motor was putting out.
It was tearing them up!

Allen_okc
05 August 2011, 0802
you know you got severe torque when your eating gears...

Allen_okc
08 August 2011, 1149
bad news - the painter didn't ride his motorcycle today so he could race me...

i guess he felt sorry for me...

EVcycle
08 August 2011, 1308
He must have seen your video! :)

Allen_okc
09 August 2011, 0801
Gee Thanks ED... :o

Lawlessind
12 August 2011, 1249
Congratulations Allen!!! Great Bike. Keep up the good work. Forgive me because it's probably in the earlier posts but what are you running for a drive system? Batteries?

Shawn Lawless

Allen_okc
15 August 2011, 0551
well the drive drive system is a way under powered 48 volt system, which is going to change here pretty quick - 16S2P right now but im going to a 16S4P headway cell pack, im still playing with the gear ratio... the place i was ordering from has held me back several weeks now... i have have no ideal of its top speed since i havent had the opportunity for a full quarter mile run...

but im still working on it, especially since its been triple digit hot weather here, i'll be taking it to the track when it cools down a bit here in oklahoma...

Thank You Shawn for compliment...

Allen_okc
16 August 2011, 1108
I get to cut the old hard tail off today and prep the frame for the new hard tail... everything should fit properly with this new refit...


:confused::confused::confused:

im not sure i understand what you mean leelika08...

frodus
16 August 2011, 1109
Just a spammer, quoting your previous postings....

Allen_okc
16 August 2011, 1110
anyway welcome to the forum Leelika08...

Allen_okc
16 August 2011, 1110
really we have spammers?

ZoomSmith
16 August 2011, 1116
Yes, we get quite a few of them.

When you see a post that is a random sentence, or a fragment copied from a previous post, please click on the "Report Post" icon located on the bottom of each post. (Triangle with a "!" in it)

Allen_okc
25 August 2011, 1056
Good News - i took the bike out for another run with the 48tooth rear sprocket and the 15 tooth motor gear - at 390 feet i pulled 41 mph...

getting better - tomorrow i'll have the helmet cam and hand held video's put together...

Stay Tuned - Same Bat Channel, Same Bat Time...

Allen_okc
26 August 2011, 0526
:O another boring video of my bike...


http://www.youtube.com/watch?v=rUOBfz009WE

EVcycle
26 August 2011, 0543
Repeat after me....72.72.72.72, :) :)

Allen_okc
26 August 2011, 0604
72.72.72.72.

Allen_okc
26 August 2011, 0613
144.144.144.144.

EVcycle
26 August 2011, 1053
Even better!

Allen_okc
20 September 2011, 0511
well bad news for the little scooter - it dies this week...

with the chopper getting closer to completion, its time to start transferring all the components...

one last ride this week and then the scooter will be dismantled... it never made it to the drag strip, but im pretty sure the chopper will at 72 volts...

i wish to Thank everyone and their help in getting this project completed, so with that said "THANK YOU"...