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Up hill battle = 2 gas

9K views 24 replies 8 participants last post by  bassiclyloudog 
#1 ·
I just converted a gas cateye to 48 volt electric
12v/12amp batts lb37cont 1000W48vmotor
I kept the existing battery for the existing cateye electric system.
Is there a way or lots of ways to add a boost for
up hill climbs. Would a different controller or an (extra bush button
connected to) an extra battery or +5 kit work.
I rode all our electrics tonight, then i rode our gas dirt bike around
for a long time tonight, the gas kicks *** all around. SPEED/TORQUE
I want my electrics to kick *** down hill and up. Let me know if it
is just not possible or what I have to do to achieve even limited results.
Cruh
Also on a side note. Is ther a way to hook up the existing cateye
dialtype speedometer to my motor wires to show MPH its a blue
wire that if I hook up to the battery shows about 12 or 13 MPH.
Cruh
 
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#2 ·
Are all the parts you have on the bike brand new? I ask because sometimes you find cheap 12 volt 12 amp batteries on some websites that end up being no good. Also is your wiring a pretty good size gauge? If it is too small it's going to limit the amount of power you can transfer to the motor.

Do you have any pics of the bike as well? As far as i know the speedometer that comes with these bikes operates off the original gas motor somehow. Most people just use a cheap bicycle speedometer.
 
#3 ·
All the electronics are brand new
It goes really fast on even ground and really really fast down hill.
But as you know when an electric starts to climb it only
maintains or struggles. I want the same results up hill and down
just like a gas. Or atleast limited results.
BIke is very heavy with 4 12volt12ampbatterys + 1 12volt8ampfor electronics
probley 125lbs

Cruh
 
#4 ·
Cruh, I understand what you mean power-wise as I have used the 48v 50amp controller. If you want REAL power get the 100amp controller. I put this in my pocketbike with 18ah/h batteries and it pulled! There was a real difference in power between the two. Up 2-3percent hills the speed would only drop from 27mph to 23-24mph with the 100amp. 100amps should not be to tough on 12ah/h batteries but, if you want a powerful afordable battery b b battery is the way to go.
 
#5 ·
Pictures? Specs? C'mon, cruh, you know the rules ... If you do something cool like this, ya gotta have pics and show it off.
 
#8 ·
I guess the only real thing would be a supercapacitor (?)Reading about the killacycle I learned they can dispense immense amounts of energy instantly. But they probably cost a ton too.
Other than that I really don't know what would help you keep speed uphill, the amount of energy in a gallon of gas takes around 1000 (?) lb of batteries to equal it. So maybe a +5 kit where you mount it with a switch would help you uphills. Thats really all I can think of.
 
#10 ·
Re: Up hill battle = 2 gas
A good plan if you really aim to beat the gassers is save up some cash and buy a few pairs of $50 dewalt 28v tool packs from tool king. Those use the same type of a123 cells that Bill uses for the Killacycle. They put out tremendous amounts of power and you can fit a large capacity in a small bike. Unlike lead.

Or if you've got RC experience you could do as well with RC lipo. Those are little more finicky with regard to being overcharged or abused (fire!) so the dewalts are a better choice unless you have mad lipo skillz.

Those are probably the best two battery options for beating the gas bikes. As the old race guys say.. "How fast do you want to go.. how much money you got?" I think that applies well to electric pocket bikes, it is possible to build some insanely fast bikes, but its not cheap! And most of it comes down to the batteries.
 
#13 · (Edited)
2 1hr dewalt chargers - $100
2 28v dewalt pack- $137
you would have to tape or wrap wires around the contacts on the battery and then unwrap them after 10min of run time to charge. The packs are 3ah I'm guessing because the milwakee 28v packs are 3ah
a very cool lightweight battery pack, but also very expensive! Anyone know why the 28v pack which looks better all around is $68 and the 18v with the big stem is $119?! I have an MX650 and MX500, 1 has near dead 12ah batts and the other has 7ah, both are 48v, the 12ah is almost 23mph, the 7ah hits 20mph....big difference! I'd need 8 drill batteries to get 12ah....anyone got $700 and a lot of wall outlets?!
 
#14 ·
2 1hr dewalt chargers - $100
2 28v dewalt pack- $137
you would have to tape or wrap wires around the contacts on the battery and then unwrap them after 10min of run time to charge. The packs are 3ah I'm guessing because the milwakee 28v packs are 3ah
a very cool lightweight battery pack, but also very expensive! Anyone know why the 28v pack which looks better all around is $68 and the 18v with the big stem is $119?! I have an MX650 and MX500, 1 has near dead 12ah batts and the other has 7ah, both are 48v, the 12ah is almost 23mph, the 7ah hits 20mph....big difference! I'd need 8 drill batteries to get 12ah....anyone got $700 and a lot of wall outlets?!
YouTube - Razor MX dirtbikes.wmv
The Dewalt packs are 2.3 ah lifepo4 cells 3.3 v per cell, 10 cells total in each pack. The milwaukee are limn 4.2 v and 3 ah per cell. You could find a better deal on batteries, a lot of those cheap hobby sites like " hobby king " have lipo cells now that are less than 400 USD per kilowatt/hour. You would need about 13 packs for 1 kilowatt hour with the dewalts, so you can see the difference in the price. The only thing is with the lipos there is the danger of fires and you have to balance them and all that. They do have some rather large packs though, you could probably get away running 4 of their larger packs. PM me if you want I have looked into this extensively. :)
 
#15 ·
Thanks for the input! Basicly it's a cost issue with me. For $200 I can get 4 14ah slas @ 10lb a batterythat sucks, but I have the harnesses and charger, 2/8/12amp car charger that takes about 80min to charge.
Plus there's that whole danger thing. Lipos are finiky, you over discharge them they're damaged, you overcharge them they burn your garage down. I'm not meaning offense, I just know MY limitations. I don't know enough about the stuff to get involved...plus that whole money upfront thing. The attraction with the drill batteries is the durable casing and ability to be highly discharge in speed and capacity without damage. you're gaurenteed 1k cycles+ Hobby lipos do the same thing but on a much smaller scale. The larger you go the more unstable...and expensive. Look forward to a few messages from me as I would love to hear your notes! Any info is good info. I just like to share my "******* perspective" as I see it from the beginers p.o.v.
Hills are an electric's downfall! any input is good input!
 
#17 ·
I suppose so, lead acid in terms of Electric Vehicles these days is antique technology so i'm always biased toward something more advanced, but totally understand keeping within your means. It's really easy to spend some big money on this stuff if you want to. Have you thought of making your own battery pack, out of nicad or nimh cells? Could be another route to take, but will take some fabricating and all that. For me, that's not a problem, i enjoy it and have most of the tools to get it done. Either way i'm willing to share all I know, maybe it will help somewhat. :D
 
#18 · (Edited)
#19 ·
Just get a different controller, and as an option lipo batteries. I am using a 24-28V Kelly controller and two 6S1P 5000mah Lipo's (22.2v per batter) in my son's mini-moto. You will decrease the amount of milage you will be able to travel but the hill will become much easier with 100 amps.

$100 shipped - Kelly Contorller KDS48100A

$45 each plus shipping - ZIPPY Flightmax 5000mAh 6S1P 25C

my problem with that is that 2 packs only give me 5ah which would be less than 10mion of ride time. I get 15min with my 7ah TOPs right now. $50 in lead or $400 in lipo, they are more powerful, but they will drain quicker...then you run a risk of over draining them, which is less of a problem for lipo than lead. You can drain lipos more than lead, you can charge lead more than lipo. If 1 lipo cell is out of balance...FIRE even with bms boards charging is not full proof. I wish I wasn't so sketched out by lipo. I have a couple plane and choppers, 1 of my 11.1v got super puffy after I used it to power some led lights on my bike. made me mad!
I am interested in kelly! I was thinking of going to 3 big amp hour batts with a 100a kelly. currently I'm running 48v 7ah on a 36v 650watt motor. thinking of running 3 18ah on the motor. I think the more powerful controller would open the motor up without over heating. I can get a 100a 36v kelly for $60, $80 for throttle and shipping...Thinking even just 3 14ah. Gotta stick with lead for now. 1 14ah high rate batt is like $36! not bad at all.
Could you send me some links for installed kelly pics? would like to see the wire connectors. I usually use 12ga wire. I don't want to go with 8ga, but I feel it's time for 10gauge.
Thanks!
 
#21 · (Edited)
my problem with that is that 2 packs only give me 5ah which would be less than 10mion of ride time. I get 15min with my 7ah TOPs right now. $50 in lead or $400 in lipo,

Ohms low states: The total current is equal to the sum of the individual branch currents.

Therefore if the battery is 5000mA each, 2 in parallel would be 2X5000mA, which is 10A. The total cost of the batteries is $200.00 for 4 batteries. These will also function like a 12 A/h pb battery.

I get 15min with my 7ah TOPs right now.

15 min on 7 A/h? I think you better check your batteries.

$50 in lead or $400 in lipo, they are more powerful, but they will drain quicker...then you run a risk of over draining them, which is less of a problem for lipo than lead. You can drain lipos more than lead, you can charge lead more than lipo.

$100 in lipo, not $400. They will not drain quicker. They have a denser energy and more capactiy the lead acid. Draining Lipo is MORE dangerous then draining Pb batteries. Pb can be dropped to 80% Capacity. Lipo's should never get under 85%.

If 1 lipo cell is out of balance...FIRE even with bms boards charging is not full proof.

If one lipo cell is out of balance it will not cause a fire unless its voltage goes under 85% or 3V per cell. When you charge you need a balance charger. they cost about 20 bucks new for a 5-6A version and they will charge every type of battery including PB.

I wish I wasn't so sketched out by lipo. I have a couple plane and choppers, 1 of my 11.1v got super puffy after I used it to power some led lights on my bike. made me mad!

You dropped the cells below 3V plain and simple. Lucky you did have them explode or catch fire. Most lipo's will just "puff" when there undervolted. Keep them above 3V per cell, 3.2 is better for battery life.

I am interested in kelly! I was thinking of going to 3 big amp hour batts with a 100a kelly.

Check your batteries. I have 3 17 A/h batts in my sons bike before the lipo's. The kelly controller is affordable and has over-current and most importantly programmable low voltage shutoff.

currently I'm running 48v 7ah on a 36v 650watt motor. thinking of running 3 18ah on the motor.

Good luck fitting 4 of them in there. With 3 17 A/h batteries I was able to run for about 30-40 minutes on a 750W PM DC motor.

I think the more powerful controller would open the motor up without over heating. I can get a 100a 36v kelly for $60


More amps, more heat, the motor will get hotter. The controller will protect it. I have a device that restrict current of temperature gets too high. Go with the 24-48V version. it opens the doors for future upgrades.

.Thinking even just 3 14ah. Gotta stick with lead for now. 1 14ah high rate batt is like $36! not bad at all.

I use 10AWG on anything below 100A. Remember gauge becomes less of a factor because we have suck a short length of wire. The reason for going larger diameter wire is to reduce resistance. In any case, bigger is better in regards to wire.

Could you send me some links for installed kelly pics? would like to see the wire connectors. I usually use 12ga wire. I don't want to go with 8ga, but I feel it's time for 10gauge.



This is the controller I am using on my sons little Razor scooter I am building. Schematic is on page 10/17. Displaying picture would really be useless because you cannot see all the connections.

http://kellycontroller.com/mot/downloads/KellyKDUserManual.pdf
 
#25 ·
So the cells are about as much as 4 14ah slas, that's 4 lipos, I'd prefer 8, but that still only gives me 15ah, but the weight and cycle life are a good reason to spend $400. HK also sells a decent 5a lipo charger for $40 Just as cheap as my car charger. My eventual goal is more than 100a...I want a torquer that will pull a wheelie from a standstill. I can't get the preformance from lead without a lot of lead, but it's half as cheap. so if I get 3years out of it that's cool. Still haven't found a way to keep my motor cool right now. I ran the bike hard in the snow, that was only 30a but it's weather proof. I have a fan for my motor now, but I can't run the snow with it.
Whole other issue. Right now I've been lucky enough to ride on super cheap batteries. Haven't had to put up a lot of cash yet. My dirtbikes were 2nd hand...$200 for all 3. 2 had worthless batteries. the 7ah fit under the cover and that's good enough for me now...3 bikes they can't all be lipo! I also have 2 razor scooters 1 a dualie and the other has a 1000watt motor.

I want to focus on making one dirtbike scream, but still run the others for my kid and the neighborhood gang.
 
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