Results tagged “Piaggio” from The GPSy EV Project

The weather was finally nice enough to commute to work this week on my Piaggio Boxer EV with Prius NiMH batteries.

Here's the data from my CycleAnalyst:

	Run #1 1.18 (To)	Run #2 1.18 (From)	Run #3 1.19 (To)	Run #5 1.20 (To)
Distance	5.2 km	4.85 km	4.21 km	4.19 km
Efficiency	45.1 Wh/km	39.2 Wh/km	42.2 Wh/km	47.6 Wh/km
Energy used	234.23 Wh	189.87 Wh	176.92 Wh	199.03 Wh
Charge Used	5.90 Ah	4.28 Ah	4.01 Ah	5.01 Ah
Max Amps	106 A	101 A	91 A	101 A
Average Speed	20.6 km/h	23.3 km/h	24.8 km/h	24.1 km/h
Max Speed	36.6 km/h	40.3 km/h	39.0 km/h	36.6 km/h
Starting voltage	---	49.9	50.2	47.2
Ending voltage	43.8v	45.9v	---	44.2v
Run time	15 min	12:30	10:10	10:24

My commute is slightly uphill on the way to work and downhill on the way back, which accounts for the difference in energy efficiency going to and from work.

The bike feels much lighter than with the SLAs and faster too (even with the gear reduction) so I have to say it's an unqualified success. I just hope I can get good life out of these batteries.

After Run #4, I was in a rush and so I put the charger on and went to a talk and then came back. About 3 hours had passed and the charger had over charged the batteries. It actually wedged the battery holder apart. So I'm worried now that my batteries will be weakened -- even though most of the bulging has subsided.

I reinforced the battery holder this morning and we'll see how it holds up.

I have the Prius NiMH batteries installed and test drove it but the snowstorm of 2009 has put the dampers on harder testing. In any case, here's the new revised bill of materials (BOM) (dated 2009.12):

Base Unit	Piaggio Boxer (1971) - 50 cc 2-stroke internal combustion engine (removed)
Electric Motor	HXT 80-100-B 130Kv Brushless Outrunner from United Hobbies - link to new version of motor - Tachs: 5600 rpm @ 43.2v nominal (4500 rpm @ 36v; 6000 rpm @ 48v) - Max amps drawn: 100A @ 43V - Max watts drawn: ~ 4300 watts - Speed: 45 kph top speed (at current gearing)
Electronic Speed Controller	Castle Creations Phoenix HV-110 (link) - 110 amps @ 50 volts limit
Throttle	Magura 0-5K Potentiometer motorcycle twist grip throttle
Servo Tester (Pot to ESC)	Boman Industries Polar-Matic PC-50 (ebay)
Power Monitor	Cycle Analyst (link)
Batteries	Currently SLA: Prius Gen 2 NiMH - 6S2P packs (12 in total) - 43.2 volts nominal @ 13 Ah - 330 watt-hours (conservative) - Range: unknown
Power Connectors	- Anderson PowerPole 75A on main connections - link - Anderson PowerPole 30A on sub connections - link
Wiring	- 8 gauge stranded copper on main power lines and motor leads - 12 gauge stranded copper on sub power lines
Lighting	- Front lighting using high-power Luxeon LED - Rear lighting using high-power red LEDs
Low Voltage (12/5VDC) Converters	12VDC converter using National Semiconductor LM2576HVT-12-ND buck-converter for motor cooling fan, front lighting (via 5vdc) and rear lighting 12 volt to 5VDC converter using MC34063 Based Switching Regulator for front lighting Another 12VDC converter using National Semiconductor LM2576HVT-12-ND buck-converter for ESC controller cooling Quark Pro BEC 3A UBEC for servo tester / RC components
Things I burned out/destroyed	E-Sky EK2-0907 Servo Tester Doc Wattson power monitor ELF 100 ESC speed controller Castle Creations Phoenix HV-110 Right index finger on burnt out ESC Various burns and scrapes

Revised bill of materials (BOM) (dated 2009.09):

[moved to after the jump]

My little Piaggio-EV is back up and running. I made the following mods:

• My replacement HV-110 is now installed in an external plexiglass box with (much) better airflow and forced as well as passive air cooling. The forced cooling is on full all the time rather than the temperature variable fan that I used to have.
• Extra caps (470 uF x 6) soldered in parallel with input leads
• (Slightly) beefier wiring used -- 8 gauge rather than 12 ga
• 75 amp Andersen PowerPoles used instead of 30A
• Wiring shortened a bit
• Thermometer probe directly on caps to monitor heat

So far, it seemed ok. After my ride to work this morning, the caps heated up a bit -- from 17°C ambient at the beginning to 37°C ambient at the end of the 5 kilometer ride. I'm working on getting even more cooling in there.

6 amps used. 30 watts/kilometer average energy expenditure.

I didn't like the wooden saddlebag style racks on my Piaggio that I had originally made. The problem was that the Piaggio didn't have adequate mounting brackets for them, which meant they were putting strain on the rear fender. Also, they interfered with the pedal action.

I decided to change the mounting system to a rear rack style. I removed the elongated double seat and replaced it with a bicycle seat. I used my MIG welder to bodge up a rear carrier, seen below. I think it looks pretty good.

More postings to follow re: the decision to change batteries and the actual battery carrier itself.

I spent a few hours this afternoon installing the HXT outrunner motor. It was a bit larger than the MY1016 that I had previously had as a prototype. And as it is an outrunner, this necessitated a different type of engine mounting.

Here you can see the base end of the outrunner motor with the power leads on the left. The X shaped bracket came with the outrunner and is what I used to attach it firmly to my Boxer's left engine support bracket.

This is the view from the top. The main body of an outrunner motor rotates, so you can't attach the motor by the side. It has to be face mounted.

Here is the left side spindle with the V-belt pulley installed. The nice thing about retaining the CVT back end on the moped is that I don't have to adjust the pulley tension, it's done automatically.

This is the right side of the motor / moped. In order to have the pedals clear, I had to shorten the right hand (prop side) spindle. I left a small nub so that I later attach a flange bracket to lessen some of the side loading on the main bearings.

I had to cut away some of the sheet metal on the right hand motor bracket to fit the motor and its spindle in. This considerably weakened the right side bracket, which is a structural part of the suspension system.

This is the right side of the motor again, from the top. The green, black, and red wires visible are the mopeds low-voltage (6V) power leads to the headlight and taillight.

When I cut part of the right side motor bracket to fit the spindle in, this weakened the right side as it was a structural component. In order to make sure nothing Bad happened, I reinforced the bottom part of the mount with a piece of L aluminium bracket.

Once the ESC arrives, I can wire everything up and take her for a spin. I'm hoping that current pulley gearing will give me around a 30 mph top speed. I'll be running her off a 24V SLA system at first, then when my NiMHs arrive, at 28.8 volts.

Higher than 30V and I need a new ESC, darn I knew I should've just bit the bullet and gotten the Phoenix HV100A.

I finally got around to downloading the photos of the first half of my scooter's EV conversion from my digital camera. Here we go:

This is the Piaggio Boxer mo-ped that I'm converting:

This is the donor Razor for the motor, batteries, and controller:

The right side is the bicycle pedal and chain section, don't want to mess with that side:

The left side has the gasoline ICE and you can see the CVT drive belt:

Front of the CVT spindle up close:

Front of the CVT spindle dismantled:

My partner had bought an old Piaggio Boxer mo-ped a couple of years ago but sitting in our garage had rusted out the engine. I decided to make it an EV conversion.

So far, I've removed the old ICE cleanly. It looks like the ICE was connected to the rear wheel through a belt-driven CVT / clutch.

My replacement motor is a small 24V / 250 watt one taken from a RAZOR electric (toy) motorbike. It's about the only thing I can find that would fit in the small area of the former engine compartment (about 4-5" wide). If the 24V works and doesn't have enough power, I'll have to see if I can find a more powerful pancake unit or mount the motor in a separate place.

I'm driving of to my nearest (? 1 hour+) tractor supply center today to see if I can find a v-belt pulley that will attach to the motor. The old front CVT pulley from the ICE won't fit on the DC motor because the spindle isn't long enough.

IF I can find a new pulley today and find some kind of engine mount, I think I can finish up the conversion this week. But I'm just guessing at the pulley gear ratio and I don't think that the 250 watt motor will be powerful enough.

The controller is rated for 24V / 30A so I could put in a bigger motor if I could find it..... Or I could hop up the voltage to 36V by adding another L-A battery.