Yet another Yellow Ninja 250 Conversion!

[Doctorbass]

When you say:

Watt Hours/Mile 3600 Wh/Mile
For every (1) hour I charge, I can ride (2) miles on average

that sound strange to me about 3.6kWh per miles!!!

the average electric car consum around 150 to 300Wh/mile so i would think you have a 360 instead of 3600 right?

Doc

[frodus]

Doctorbass,

there's no way its 3600, I don't think he's doing the math right. His bats are 35Ah, and 72V, ~2500Wh.

He says 2 miles per hour of charge, with 24V charger (3), that'd be 3A charge in one hour, so 3A, on a 72V pack is about 216Wh and he gets 2 miles, which is around 108Wh/mile, give or take. This is a normal wh/mile measurement.

Also, I'd recomend AGAINST tapping off the battery pack for 12 and 24. Those 2 batteries WILL wear out faster, now matter how you cut it. How are you balancing the pack? 3 24V battery chargers will only balance 3 packs of 2 batteries. The bats you're tapping off are going to use more power, even if its only a few amps. Even if you charge them back up to max, there is more wear on them.

I'd recomend using either a DC-DC converter, or a small aux battery or two (I know the kelly is 24V, and I don't know WHY the f*ck they did that).

[pgt400]

yes, I obviously did a mis-calc. My watts per mile is ~108 on average. I am looking for a 16x4 LCD display with pic controller I can program to crunch data with.

[frodus]

here's a 40 pin Pic board with backlit LCD on it and a FTDI USB chip (so you don't have to hunt down a serial port, if you even have on on your laptop).
http://www.sparkfun.com/commerce/produc ... ucts_id=27

here's a 28 pin pic with serial
http://www.sparkfun.com/commerce/produc ... ucts_id=26

I've got this from them
http://www.sparkfun.com/commerce/produc ... ucts_id=20

Works good for little projects.

[pgt400]

Great thanks. In a former life some 15 years ago a did alot of pic programming for motion control. I'm thinking of adding a 24v DCDC convertor for the 12 volt. I only need about 50 watts for my lights on average (can turn off my headlight). With 24 volts that will be 2 amp draw, plus it will be an equal load across 2 batteries and the 1 charger. I was also thinking of doing an individual 12 volt balance charge once a month.

[frodus]

Great thanks. In a former life some 15 years ago a did alot of pic programming for motion control. I'm thinking of adding a 24v DCDC convertor for the 12 volt. I only need about 50 watts for my lights on average (can turn off my headlight). With 24 volts that will be 2 amp draw, plus it will be an equal load across 2 batteries and the 1 charger. I was also thinking of doing an individual 12 volt balance charge once a month.

its not the unbalancing, per se... its the total lifetime amp draw and the effect that will have over time. at 2A it might not be a ton, but you are drawing more off those batteries and discharging them more.

I'd consider that USB programmable one... seems like a great fit for a monitor. only 16x2, but you can do menu's with the button. Even have a finger button so you can do it while riding.

[pgt400]

Really happy with the PowerStar batterys so far. I have about 25 cycles on them. Today I got 20 miles with lots of 45 mph runs, batts were at 71 volts when I came in. I use the regen for most stops, only using the brake once I am stopped. Not sure were 11.8 volts per cell fall in the discharge scale but it surely has more left. I also changed out the front 12 tooth to a 13, picked up about 3 mph. I decided to make 70 volts my discharge limit. The guy at PowerStar said I can take it done to 10.5 each battery but that seems a bit much....63 volts.

[Jay64]

Hmm, I have a 250 ninja at my house right now that had a really gummed up gas tank. A friend from work owns it and had asked me to help him get it running. I pulled out the fuel petcock and it was beyound gummed up. The gas had actually turned to rubber! I was telling him how much it would cost to clean out the tank, carbs and re-sync them. He didn't have the money so he told me to hold off on fixing it. He just called me last night saying he was leaving the state right then and heading back to Cali. He wanted me to get it fixed and charge his dad. His dad would then try to sell it. I asked if I could just buy it now for a bike for my girlfriend. But now I am thinking about buying it and converting it using this as an example.

[pgt400]

Do it, and as a bonus, you can get $600-$700 for the engine on ebay! Turns out there is a midget racer go kart class that uses them. They snap them up as fast as they are posted.

[Jay64]

When I asked him about it, he wants me to get it running first, and then have them make me an offer of how much they will sell it to me for. Screw that, I would rather buy it now, when it is not running rather then do the work for them just for them to charge me more money. I will keep talking to him about it though.

[pgt400]

I bought my 03 for $1100. Had 1020 miles on it. The carbs were gummed up, sitting for 3 years. I got it running in less then 1 hour. Sold the motor for $665 on ebay. Its a good bike to convert. I managed to stuff 6 35 AH batts in mine. I am very happy with it so far. Next spring when I go for Lifepo4's will be even better!

[pgt400]

Put in a 24 to 13.2 volt 10 amp DC/DC converter this morning....Junk! Eff is around 50%, may as well use a resistor. The input was 26.5 v @ 2.4 amps, Output was 13.2 volts @ 2.2 amps. It was a VR-1 from Ebay, build quality look ok poor design, should have been around 85% eff or better. Glad I checked it, its commin out!

[Jay64]

That sucks, sorry to hear that. Hope you get a better replacement for that.

[nasukaren]

Put in a 24 to 13.2 volt 10 amp DC/DC converter this morning....Junk! Eff is around 50%, may as well use a resistor. The input was 26.5 v @ 2.4 amps, Output was 13.2 volts @ 2.2 amps. It was a VR-1 from Ebay, build quality look ok poor design, should have been around 85% eff or better. Glad I checked it, its commin out!

After bad luck with an ebay special, I made my own DC-DC converter using a National Semiconductor LM2576HVT-12-ND buck-converter from Digikey. It's rated to 3A passive and 5A active cooling. You could easily hook 3-4 of them up in parallel to give you 10-20A of 12VDC.

The schematic I used is on my blog.

Karen

[nasukaren]

p.s. Have you thought of getting a high-voltage bulb for your headlight and just running it straight off your high-voltage line? That way you don't have to fool with DC-DC converters. You can get 100VAC halogens and just run them a little cool.

[pgt400]

Well I wanted it for the contactor too. I put in a headlamp switch and was looking for an LED bulb but I like your idea.

[pgt400]

Put a combo volt/current meter on the other day. On accel I briefly hit 230 amps, 25mph is about 16 amps, 35 about 30. And cruising at 50 mph is 51 amps on flat road. This is with 14/72 gearing, 72 volts sla. Also connected the regen through a relay to the brake switch. I have it set at 20% regen which is close to -40 amps during 50 mph braking. I'm thinking about using a simple voltage to frequency converter chip to use the tach for a meter instead.

meter.jpg

(87.71 KiB) Downloaded 830 times

[frodus]

I'm wondering if there's a desire for a little "kit" that takes in the voltage off a shunt and outputs a fequency? I know you can breadboard it, but I definately like the functionality on my bike (we do it through the programmable controller).

[pgt400]

Well it would be nice to use the tach, but I imagine the market is pretty small. It would be a nice add on for Kelly. Watt hours would be good as it would use the complete range.

[drewjet]

I think the tach turned into ampmeter is a really nice trick. It would be nice if there was a kit for it as those of us that have no electronic design/build ability.

[drewjet]

Bike Looks great. I showed to a few guys and work and they all liked it. Nice Work!

what is your top speed now? and range?

Drew

[Jay64]

Yeah, having the tach as a meter would be awesome. That would help to make some really clean builds. I have never done it before, but I know you can change out the background plate for your tach, so you would even be able to re-calibrate the markings to show true what the needle is pointing at. I think that is a REALLY great idea guys.

[frodus]

Well it would be nice to use the tach, but I imagine the market is pretty small. It would be a nice add on for Kelly. Watt hours would be good as it would use the complete range.

The market seems pretty decent for a little guy like me

i mean, all those cars and motorcycles out there with a Tach, some use it as their tachometer, but some don't use it at all.

I mean, as stated, its just a voltage to frequency converter, but its got to be able to be calibrated, and adjustable. I'll start looking into it.

[frodus]

Yeah, having the tach as a meter would be awesome. That would help to make some really clean builds. I have never done it before, but I know you can change out the background plate for your tach, so you would even be able to re-calibrate the markings to show true what the needle is pointing at. I think that is a REALLY great idea guys.

I just made mine so that each 1000RPM is 50A

so the 1 on the gauge is 50A, 2 is 100A. You could just do watts as well, so the full range is actually Average watt usage, you could even have a button that toggles between volts, current, watts, etc (little LED's tell you what "mode" you're in).

[pgt400]

Bike Looks great. I showed to a few guys and work and they all liked it. Nice Work!

what is your top speed now? and range?

Drew

Thanks! Its geared for 50 mph. 14/72 with a 50rpm/volt Mars. I was looking at the brushless (r/c experiance), but it seems the controllers are not very eff at the higher current rates ....yet. I get 20 miles before the LVC kicks in under acelleration. Doesn't matter if I do 2, 10 or 20 miles, as soon as I park it I charge. Looking forward to spring upgrades...PSI's and possibly an Agni motor for 84 volts.