Travel

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Overview

Electric motorcycle travel is in its infancy, and involves some unique challenges and rewards. It's not like regular motorcycle travel, electric car travel, or electric bicycle travel. When practiced well, it involves a lot of discipline throughout a day but is quiet and engaging like bicycle travel while covering much more ground.

For the sake of this section, "travel" means any riding plans that extend beyond the capacity of one full battery charge.

Evaluation

To get the most out of a Zero for travel, focus on distance covered per day rather than literal speed:

  • Rate your vehicle's charging in the effective distance you can recover per hour.
    Obviously this depends on your projected trip speed but 55mph or 80kph is a reasonable default.
    At 55mph, the range of a 2016 Zero S ZF13.0 is 98 mi.
    Using the stock charger (1.3kW), the nominal 11.4 kWh used is recovered in 8h40m.
    So, the stock charger recovers at a rate of 98 miles / 8h40m, or 11mph.
  • Rate your vehicle's range by knowing the discharge rate (Wh/mi or Wh/km) at various speeds in the configuration you'll use when traveling, including cases and bags.
    Drag rises nonlinearly (square function) with speed, so time spent going fast is offset by that time squared charging, and you cover less ground... except on the last leg.

Upgrades

A Zero when delivered is a good commuter vehicle, but not immediately suitable for travel because of the long charge time of several hours, and because of its limited range per charge.

Consider what's needed to achieve your travel goals. A stock Zero is not capable of more than 200 miles per day without traveling very slowly.

Factors
  • Chargers
    Increase the rate of range recovery per minute or hour of charging.
  • Battery (Power Tank for most).
    Increases the range of a single leg by 25% but adds to mass and uses up the tank area, and doesn't increase daily mileage over multiple legs.
  • Storage.
    Allows storing modular chargers, and of course, actual personal needs for a trip.
  • Efficiency.
    Reduce power consumption at all speeds, increasing leg range. The best improvements here reduce the nonlinearity of drag with speed, meaning you can travel faster without covering less overall ground.

For your vehicle, start by figuring what distance per day it can cover reasonably, and what kind of investment is worth a travel experience you like.

Examples
  • With a stock 4p 2016 Zero S ZF13.0, the nominal capacity is 11.4kWh, the 55mph range is 98 miles, and the recharge rate is 1.3kW.
    So, you could travel for 1h47m at 55mph and then stop for charging, which would then take about 8 hours. This is a full trip leg.
    You could repeat the leg for a total of 196 miles over a total time of 12 hours.
  • If you just want to cover up to 250 miles per day, the simplest solution is to add a Power Tank and deal with the 10 hours of charging needed to charge the battery with the power tank added, and travel for two legs each day.
    However, adding battery capacity adds to your charge time as well as the length of each leg of your trip, unless there is a change to the charging rate.
  • If 250 miles with a lot of time spent waiting to charge isn't suitable, and you install a Charge Tank instead of a Power Tank, your charge time goes down to 3 hours even though you're stuck with the original trip leg parameters (98 miles).
    With a Charge Tank, you can add another trip leg and reach 300 miles in the same total time of 12 hours.
Travel Rates (Stock ZF13 model at 55mph)
Travel Leg Charge Leg Daily
Configuration Capacity (kWh) Range (mi) Leg Time (h:m) Charge Rate (kW) Charge Time (h:m) #Legs Range (mi) Time (h:m) Avg Speed (mph)
Stock 11.4 98 1:47 1.3 8:45 2 196 11:30 17
Power Tank 14.0 120 2:10 1.3 10:40 2 240 15:00 16
Charge Tank 11.4 98 1:47 3.8 3:00 3 294 11:30 25
1C Charging 11.4 98 1:47 11.4 1:00 5 490 13:55 35

This roughly illustrates how upgraded charging equipment improves your daily mileage in a way that adding to battery capacity doesn't.

If the specific mileage goals are not critical, the average speed (as a matter of how much ground is covered over a whole day) points out which best use your time.

Obviously, it's helpful to have both a battery upgrade (to have more freedom in arranging trip legs that are long or can go faster) and fast charging, but the tradeoffs are important.

Charging

The goal with a charging upgrade is to minimize the time spent charging. The charge rate is the most significant factor, but setup and teardown adds some overhead per charging stop.

Mid-Range Charging Rate
6.6kW is a goal that ensures that most J1772 stations can be used fully, and reduces charge time significantly enough (1h45m for the ZF13.0) to accomplish 350-400 miles per day.
Upper-End Charging Rate
Zeros can only be charged at a 1C rate (meaning 0-100% in 1h), so the goal for travel is to be able to reach that level as often and as reliably as possible.
For the ZF 13.0, 1C corresponds to charging the nominal 11.4kWh in one hour, so it's effectively an 11.4kW limit.
For 220V AC input, 1C means 52A at the source (likely a little higher because of conversion losses).
1C means 110A DC output current at the nominal 102V through most of the charge mid-range.
Being able to use a NEMA 14-50 outlet at a reasonable rate (~9kW) is significant, as is being able to use two J1772 stations at the same time to reach just under the 1C rate.
This means arranging your power inlets and cabling to get the most opportunities out of a minimum set of hardware.
Note: The Power Tank upgrade has the nice side effect of raising the 1C rate to 14.2kW, although obviously the time to charge will still be 1 hour for 0-100%.

Efficiency

Although charging makes a large improvement to a Zero's travel performance, charging has limits in capacity and benefits, and doesn't help with per-leg range and freedom of mobility.

For these reasons, it's important to consider aerodynamic streamlining to some degree.

By reducing the amount of energy consumed per mile of travel, the amount of charging needed to cover a distance goes down by the same amount.

One way to look at travel optimization is the ratio of road time to charge time: efficiency improvements raise that ratio.

Example
The following illustrates how trip legs play out by percentage drag reduction.
For the sake of argument, 55mph is assumed just to make it clearer what happens to range and time traveled.
Travel Rates (ZF13 model with 1C charging at 55mph)
Travel Leg Charge Leg Daily
Configuration Capacity (kWh) Drag (%stock) Range (mi) Leg Time (h:m) Charge Rate (kW) Charge Time (h:m) #Legs Range (mi) Time (h:m) Avg Speed (mph) Travel/Charge time
Stock 11.4 100 98 1:47 11.4 1:00 5 490 12:55 35 1.78
Windscreen 90 109 1:59 5 544 13:54 39 1.98
Front fairing 80 122.5 2:14 4 490 11:55 41 2.23
Fairing+Tail 70 140 2:33 4 560 13:11 42 2.54
Rolling Resistance
Lower rolling resistance tires will make a small but meaningful dent in power consumption.
Keep the tires inflated above the recommended range but mind that overinflated tires are more sensitive to punctures from road debris.
40-45psi is a reasonable arrangement.
Overall, you might expect about 5% range improvement from these efforts.
Aerodynamics

A windscreen is the baseline aerodynamic improvement worth making, in terms of return on investment and minimal effort.

Beyond the basics, some kind of fairing and streamlined storage is advisable.

The Vetter fairing plan is the current gold standard, but only Terry Hershner has taken the most advantage of this on a 2012 Zero, and a 2013+ mount or repeat is still to be seen.

Any streamlining choice should address major aerodynamic problems with motorcycles:

  • The full speed airstream hits the rider's body sitting upright.
    Solutions: tuned windscreen, front fairing, and handguard covers.
  • The airstream closes around the rider's body immediately afterward.
    Solutions: a curved seatback or other formed shape as the front of a tail assembly that smoothly draws air back together.
  • The wheels are in the airstream, and the spokes on the upper half of the wheel are traveling forward at up to 2x the vehicle's speed.
    Solutions: wheel covers or enclosing the wheels under fairings.

Information Management

Your primary concern while riding is making sure that you are currently on track with your plan for that leg. This means knowing whether your current operating efficiency matches what you planned on, because if you don't, that leads to further delay in charging at the next stop, or less margin for error, and definitely more time spent over the course of the day making up the loss.

Weather
Check the local weather using a service that reports windspeed and direction visibly.
Check whether large temperature swings will happen or where to expect precipitation.
Check winds and temperature ahead on your trip to anticipate any difficulties and maybe luckily route around them.
Dash
Use the Range Remaining indicator on the dash instrument cluster's first slot to calibrate remaining range.
It does have some inherent error, but it is subtly responsive and easier to think about in concert with a GPS/mapping app routing you to the next charge point that also reports remaining range.
Use the Wh/mi (Wh/km) reading.
There's some disagreement about whether the inaccurate momentary reading or the trip average is more helpful, and this seems to be a matter of preference.
Mobile App (riding)
The Zero mobile app can show a dash screen with live indications while riding.
Power output is one direct measure there that is worth considering using.
In hot weather, motor and battery temperature may be worth monitoring to maintain a steady level instead of hitting the warning limit.
Charging
Use a charging network with online reporting like ChargePoint to notice disconnects or station faults.
In hot weather, check battery temperature while charging.
It's okay to build up heat in the batter towards its limit, if while riding enough heat can be stripped away to offset this.

Planning

Plan a day as a series of trip legs connecting charging opportunities.

Build buffers into your leg estimates to account for various unplanned difficulties:

  • Bad/failed charging stations, requiring a backup plan to another station.
  • Heavy headwinds that increase drag, or cold temperatures that reduce range.
  • Large elevation rises that consume charge faster (descents recover some of this but not enough).
  • Getting lost!

Time Management

Obviously, charging opportunities will be rare for some time, and you'll be spending (for now) one-third of your day spread across charging opportunities.

With that in mind:

  • When arriving at a charging station, set up and verify charging immediately after getting off the bike.
  • Politely delay answering questions from onlookers until your charge session is working at the level you need.
  • Pick charging locations where you can do something that fits your priorities (such as):
    Town centers.
    People to talk to.
    Good eating options.
    Scenic views.

Plan or adjust upcoming legs while charging.

Daylight Management

With the overhead of charging in intervals spread throughout the day, electric motorcycle travel requires a different mindset than travel with a conventional vehicle.

To avoid riding at night where fatigue multiplies, eyesight is poor, and the weather colder, plan the day to start at dawn before eating more than a snack, then eat breakfast at the first charging stop, and maintain a steady pace all day to cover ground as much as possible before sunset.

Build towards this relentless all-day pace with some practice half-day runs. Observe fatigue onset in various conditions.

Finding Chargers

The state of the art in finding chargers is to use a number of mobile apps to map charging options:

Prioritizing
  • You want to maximize your total charging capacity but it doesn't matter if the station exceeds it.
  • Make sure the apps that chart multiple kinds of chargers are filtered by default to the chargers you can actually use.
  • Read user feedback on chargers ahead of time, particularly on PlugShare, to see whether they are broken or unreliable or have quirks or access limitations.
Experimental App
One mobile app in beta is promising but still rough: evTripn seems to model vehicles, including Zeros, very carefully to help identify and minimize the risk of mis-estimating range.
Particularly, it uses the vehicle's mass and calculates losses from elevation changes to predict where a charge is needed on a map. Windspeed and temperature are also accounted for in some way.

Risks

Electric motorcycle travel is in its infancy and presents new risks:

  • Electronics failures
  • Software faults.
  • Lack of (or drastic limits to) the available electricity to charge!

Zero as a small manufacturer has a single platform with some inherent risks:

  • Belt failures.
  • Bearing failures (especially pre-2015).
  • Suspension failures (again, pre-2015).

Carrying a spare belt to replace remotely or have a local mechanic replace could help. Roadside belt replacement on a Zero would be difficult, though.

Fatigue

Motorcycle travel fatigue is very real and can lead to an accident as one's attention span degrades.

A reasonable expectation is that one can travel three full days before requiring some kind of break. The reality is that everyone's stress and fatigue build in different ways, so test yourself before making demands of your endurance.

Common factors
  • Hydration.
  • Sun in the eyes or riding in darkness.
  • Excess heat (beyond 85F).
  • Cold temperatures (depends on gear, but below 70F conservatively).
  • Soreness.
  • Boredom!
  • Winds or gusts.
  • Rain or snow: drains body heat without layered protection or heated gear.
Electric-excluded factors
  • Gear shifting.
  • Clutch operation.
  • Vibration.
  • Engine noise.
  • Turning against the gyroscopic effect of moving engine masses.
  • Chain oiling.
  • Fluids (oil, coolant) that must be clean and not leak.
  • Spark plugs, fuel injection, or carburetor tuning.
  • Radiant heat from engine and muffler.
Electric-specific factors
  • Range anxiety.
  • Anxiety about being stranded if a charging system fails.
  • Anxiety about unrelated failures that compound because a local mechanic is unfamiliar.
  • Electric motorcycle platforms are not ergonomically designed for touring yet (seat, fairing, geometry).
  • In hot conditions, an air-cooled Zero recovers slowly from heat induced by charging or operating at speed.
  • In cold conditions, no radiant heat from engine and muffler.
Fatigue management
  • Stay hydrated.
  • Stretch regularly and take walks (conveniently while charging).
  • Plan ahead to manage charging risks.
  • Wear appropriate gear and maintain comfort levels (open vents or add layers to maintain temperature).
  • Keep your options open: a flexible approach means stress doesn't pile up when something goes unexpectedly wrong.
  • Have a general set of backup plans: anticipating what you can do in the worst scenarios will make them less daunting.
  • Slow down! High speeds tax the vehicle and the body/mind.

Charging Etiquette

For RV parks, call ahead with an idea of when you might show up and explain what power you're looking for and how long. Estimate the cost in local power of the charge and offer a token amount of money to cover it.

For EV charging, don't unplug a vehicle that is in the middle of charging. Some EV models have alarms that sound when you unplug them unexpectedly, even if they've stopped charging.

If you plug in and walk away for a while, a card attached to explain who you are and how to contact you (mobile phone number) may help avoid being unplugged, which would waste your time and interfere with travel plans.