Whats your top speed with 48 volts?

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Nov 20, 2010
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I added a 4th 12v SLA battery to my 26 inch 750 watt mountain ebike. So far I only drove it a few blocks but it seems I went from 20 mph to 25 mph - I was hoping for 26 to 28 mph. I have read that a 700c will do 2 to 3 mph faster.

Is this what most folks get?

Granted it takes a while to get up to 25 and by that time I need to start looking for traffic at the next intersection and slow down. ( in a suburb) 25 feels nice on a bike so far but once I get used to it, I may want to go faster.

Would a new Lipo or LiFePo4 setup give me 2 or 3 mph more?

I ask this because my SLA's are 2 &1/2 months old but only 2 are the same age, one died and was replaced 3 weeks ago, now added a 4th - I do not know if varying ages hurt the speed, I do know it has seemed to effect range - don't know why - I have never let them go down past 50 % and I always charge them asap.
 
48 volts ...20 amps ... 24 mph

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Electric Rider said:
Would a new Lipo or LiFePo4 setup give me 2 or 3 mph more?

I would say yes simply because your losing a crap load of weight going to Lithium..Lead Acid is terrible choice for e-bikes buddy get rid of it ASAP.

KiM
 
This is the battery i'm thinking of getting provided I cannot find one cheaper - http://www.pingbattery.com/servlet/the-12/48V-15AH-V2.5-LiFePO4/Detail (48v 15ah)

My SLA's are 12 ah so I cannot see going down to 48v 10 ah battery - range will still be lower than 12 ah sla's right? I figure this way I get more range than I have now. Ping charges 485.00 plus 109.00 shipping for the 15 ah. Total of $594.00 That's getting really tight for my budget.

Total for the 10 ah is only 348.00 plus 80.00 shipping, Total 428.00 but I feel I would give up range. Going from 10 ah to 15 ah costs $166.00 dollars U.S.

I don't like the idea of dealing with Ping and China at all because they have no honest government regulation. All the American companies who sell a battery like this are all a lot higher priced. I'm dammed if I do and dammed if I don't.
 
If its 750 watts at 36v then its 1000w at 48v. 1000/48 is 20 amps which is hard for a Ping 10AH battery, the 15AH will do better.

Just from aerodynamics : an upright rider can go about 29mph on 1000W, If they are a racer in spandex, tucked, aero bike elements they could get 39mph. But the motors have a max RPM depending on their construction that, together with the wheel size, can have a lower speed limit.
 
Electric Rider said:
My SLA's are 12 ah so I cannot see going down to 48v 10 ah battery - range will still be lower than 12 ah sla's right?
Actually your SLA are probably more like 6Ah or maybe 8Ah if you're lucky, with the high currents an EV setup draws from them, due to the Peukert effect. (faster you draw power out, the less total you can get out of them, much more pronounced with lead-acid than any other commonly-used EV chemistry).

Using 36V of 18Ah SLA, I could get (with generous pedalling) about 12-15 miles of range on CrazyBike2, if I was lucky, at perhaps 15MPH-ish, and that's with the advantage of it being a lower-slung semi-recumbent bike. But with DayGlo Avenger, a regular upright bike definitely using more Wh/mile than CB2, I could get about the same range out of only 9Ah of 36V NiMH, about same pedalling and speeds (before I damaged the NiMH due to charging problems).


Back to the topic of the thread, on CrazyBike2 the top speed with 48V of 13Ah NiMH is ~23-24MPH, and about 2-3MPH faster with 48V of LiFePO4 (becuase it's setup about 4V higher voltage). I have not actually done a full speed test, as I think that I could get even faster on a long enough run. At 60V of 13Ah NiMH even with the significant voltage sag from the damaged cells at high current, I got about 31MPH at the Undead Race back in October, on the short section of straight track before I had to slow for the turn. Eventually I'd like to find somewhere around here locally with a long enough straightaway on a private road or something so I could test the actual fastest speeds and how long it takes to reach them.
 
Samba - I consider it a 750 because that's the high rating. Actually it's a 500 W that has been modified with heavier wiring so you can use it at 750 without loss of heat or it burning up on you. (according to the company, they call the motor a 500w - 750w) AFAIK it has not had more windings added to it.

Given this understanding would you still say the 15 ah is better than the 10?

ambewrwolf - Coupled with the info above, I have never ran my bike full out till I hit my range limit - so I do not really know what my range is. I know my throttle has 3 lights on it and after about 3 miles the third light winks out. On that return trip I was able to make it back just when the second light winked out. This is the first and only time I have ridden it this far at a time. So I figure 9 miles which is horrible when my ebike kit's maker says 14 to 20 miles - with 3 x 12v SLA sold with the kit. ( and I only weigh 135 lbs)

Now, How can I know what expected range of the Ping LifePo4 10 ah and 15 ah would get me? If given the info above the 10 ah would be better And get me 20 miles range, perhaps going with it wont hurt me? I only wanted the 15 ah for more range basing that on my current setup.. but can afford the 10 ah better.. I don't wanna screw myself as I can only buy one battery.
 
amberwolf said:
Eventually I'd like to find somewhere around here locally with a long enough straightaway on a private road or something so I could test the actual fastest speeds and how long it takes to reach them.

hehe .. what you need AW :lol: is some "aerodynamic" aids and perhaps a couple of extra solid fuel rockets
to help you get up to speed faster :wink: I have taken the liberty to put together a design concept-->

AW_Star_Ship_Crazy_bike_2.jpg
"I'm giving it all she's got captain Captain!"

With some frontal aero and perhaps a couple of solid fuel rockets from the model store Crazybike 2 could
be pushing the 100km/hr limits :shock: :mrgreen:

KiM
 
SLAs have terrible sag, so it wouldn't surprise me if you gained a few mph just going to lithium, even lifepo4.

Many people have mentioned that lithium batteries make things fast in comparison to SLA. Unless you are using wickedly huge SLA batteries, SLA sag is always a problem.
 
LOL AJ.. love the photoshops

remind me not to post any pics on here :lol:
 
An Ebike with Warp Nacells and Bussard's ramscoops ( for Hydrogen collection) Whoo Hoo! Now we're talking.. Where's the YouTube video?
 
41.7 @ 1500 watts(probably a tail wind when this happened) normally it's 36-38mph @ 1500 watts
3000 watts should get me to 44 or 45 but I haven't tried yet.
 
I added a 4th 12v SLA battery to my 26 inch 750 watt mountain ebike. So far I only drove it a few blocks but it seems I went from 20 mph to 25 mph - I was hoping for 26 to 28 mph. I have read that a 700c will do 2 to 3 mph faster.

Is this what most folks get?

When I had my crystalyte 408 with 20 amp controller, 36v upgraded to 48v took me from 18 mph to about 23/24 mph.

With my phoenix, 36v to 48v upgrade goes from about 24mph to 29 mph but this is with a 40 amp controller. I think the phoenix is about 1000 or 1200 watts at 48v. for 750 watt, i think around 25 mph is about right-- but a lot depends on weight. Going to a light city/urban/road bike, using lipos, going on a flat with no wind and maybe you can get about 28 mph. I'd probably consider checking you sla batteries under load. If they're sagging a lot under the load, maybe that's the reason for the disappointing speed.
 
We had customer who was 5'7 160lbs got this electric mountain bike to 34mph during a test ride. Its a 48V 12AH Lifepo4 pack.

4 SLA batteries are too heavy for a bike in my opinion. Just the weight of the SLA's will not increase your speed much.
 
have NO worries about dealing with ping.... he has p0roven himself to the members here may times ...on trike[230lbs with me] and 36v 20amp battery...40kph.... 70k distyance withy some pedaling
 
26 mph on a 9C (2807) with 12s3p lipo...and I'm ready for a 60v upgrade to break 30 mph!
-Bruce
 
With a 26" 9x7 9c I was at mid 20's on 12s lipo, which is 44.4v nominal.

I would consider a set of turnigy lipos instead of the ping,, if you don't mind putting the minimal effort it takes to care for them and buying a little more expensive charger.
 
Flat 37-38 mph with 48 volt 20 amp hour Cammy_cc LiFePo4. Phoenix racer hub. It's the folding commuter bike that won 4th place in the Undead Race in Tucson. The best showing yet for electric bikes in Tucson. Too bad my race bike got a flat during qualifying. She was sporting 72 volts @ 20 amp hour Headway with a Phoenix Cruiser hub. I may have won the race with that one. Considering that I had to start the race at the back of the pack, because of flat on the qualifying round, my 48 volt commuter bike did an awesome job for me.
 
My 6x10 9C goes a whopping 20 mph. on 48 v sla woohoo 8)
 
I can get 43kph on the flat with a 9C 24amps 12ah battery. This is on a heavy tandem. I haven't tested this with my wife on the back.
 
In 2008 I raced in the ePower Challenge with four 12v 18Ah SLA batteries (48 lbs) and a C'lyte 406 hub motor in a 26" wheel. The track had two feet of elevation gain and something like 12 corners that killed time due to wheel scrubbing of a tadpole trike. My race results were as follows;

4 12V AGM 18Ah
23.4 miles race distance in my category
34.2 mph/max speed
31.1 mph/avg speed
335.7Wh--->14.28Wh/mile

The following was the readout of my Cycle Analyst at the finish of the race;
20.51Ap
44.86Vm
969.2Wp
6.951Ah
50.5V resting voltage at end of 23.4 mile race.
Race time was 45 minutes 10 seconds.

2529760806_71e49cee41_z.jpg


In 2009 and 2010 I used a 36V Headway LiFePo4 pack (20 lbs) with a 408 C'lyte motor driving the bottom bracket and my race results improved in efficiency but dropped 1mph in over all speed. The biggest difference was that by using a bottom bracket drive I could climb any local hills in the area now.

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Bill
 
As you see from the previous posts, the particular motor used makes a big difference due to differences in windings, and differences in magnets width and strength.

The Ping plan is good, you won't get ripped off by Ping. But shipping is imperfect, so occasionally there is a problem, which Ping does his best to solve without resorting to shipping back the battery. However, if your need for speed increases much more, you will be bummed that you didn't go for lipo, which is MUCH easier to add voltage to later.

As for wheel size changes, you'd be better off to go to a faster winding motor. Two less expensive solutions are a 9 continent 2806 from ebikes-ca, or the sensorless aotema from High Tech Bikes. Either of those should get very close to 30 mph on 48v. ( btw, 48v ping charges to about 58v)

Personally, I have gotten about 29 mph from the aotema, and 27 mph out of the 9c 2807. Flatish ground, no pedaling, rode both ways and averaged speed, etc etc.
 
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