|
Welcome to EVdeals!
We've offered a unique collection of products and services to the electric
|
|
ELECTRIC
EVdeals Policies
© 1999-2011 EVdeals.com
|
Stealth II Dyno Report The Stealth II is essentially a Hoverboard minus the machined aluminum wheels and suspension system. It therefore performs in all ways like the Hoverboard tested previously. For this reason, I have included much of the original Hoverboard report below, along with the unique features included in the less expensive Stealth II. DIMENSIONS: (to be obtained) PACKAGING: The unit was quite well protected during shipment by the use of "Instapak" foam bags. No signs of finish scuffing, or shifting of the scooter were noted. The outer container was complete and undamaged. DOCUMENTATION: Very thorough and easy to understand. Currently, the manual is the same as included with the Hoverboard. There is at least one new item (the "Flux Capacitor") not mentioned. (see below) QUALITY and DESIGN: Spoke wheels are of injection molded plastic, and accurately formed. The drawn aluminum battery pan, doubling as a heat sink for the controller and charger, is beautifully incorporated around the oversized monotube frame member. (1-13/32 tubing) Steel standoffs rise up through the pan, supporting the deck and transferring a portion of the payload directly to the frame. This is a clever design element! All welds appear to be TIG, and quite professional. Frame members, battery pan, and handlebar assembly utilize this weld.The headset bearings are more than adequately sized. The "umbrella" like steering tube folding mechanism is quick and positive locking, both in the up and folded position. The solid rubber 6-1/2" x 2" tires are molded true, and should perform well on paved surfaces with their "slick" style contact surface. However, operating the scooter on wet surfaces could be treacherous. Heavy plastic cap molding surrounding the battery pan and wooden deck contact area provides an adequate water seal, while allowing easy removal of the deck. Also, I like the use of rubber tubing to guide cables into the battery compartment. The 7 layer plywood deck (appears to be mahogany veneer) with anti-skid strips is strong and should stand up to considerable abuse. At 10-1/2" x 22", it is nicely sized for this machine. I would, however, take the time to "finish" the routed edges more thoroughly. They are somewhat "rough", and detract from the overall "fit and finish" of the product. The reflective "wrap" on the steering tube, doubling to secure the brake and throttle cables, is effective. The test scooter did not ship with a kick stand, although one is not really necessary. The unit will stand by tilting it over to one side. I still think one should be added. TECHNICAL: Both controller, and charger circuit boards are of high quality with many surface mount components for reliability. They are well protected, and incorporate various quick disconnect style plugs for ease of removal. The heat dissipating elements of both boards are effectively heat sinked to the large aluminum battery pan. Through comparison with an older model charger circuit board, it is clear that a component change has been made to reduce the "finish" voltage applied to the batteries. This change, along with a new recommended charge time, is expected to eliminate the overcharge condition found in some older models. A newly added feature is the "Flux Capacitor", or "fuel gauge". This item consists of a five bar LED battery voltage monitor built into the deck just in front of the rider's left foot. Based on my tests, this meter performs quite well as an indicator of battery condition during both charge and discharge. The new brush-less PWM motor, a Litton model BN34-25AL-04LH with large 15/32" shaft, is quiet and extremely controllable at slow speed. In fact, combined with the well designed electronic controller board and finger operated throttle, I was able to maneuver around the shop at speeds well under 2 mph with total speed control. (something I’ve never been able to do with other scooters) A temperature strip, indicating 86 to 140deg F is attached to the motor body and easily readable. Under full speed testing, the motor case temperature never reached maximum, and no sign of overheating was observed. It is my understanding that various drive roller diameters will be available, to accommodate specific riding conditions. Drive roller tension is automatically adjusted by the pivoting, spring loaded motor mount. Four Yausa 6 volt, 10A/hr (estimated) batteries in series provide 24 volts to the motor controller. Although I would prefer to see no more than two batteries in a series hookup, (for battery equalization purposes) occasional voltage checks should provide ample warning of battery deterioration. Replacing the "weak" battery will prevent over or under charging of the remaining three units. Although I was unable to road test the braking system, the two stage design should prove quite effective. A light squeeze of the lever activates the rear wheel dynamic braking action of the motor , while a further movement engages the front wheel caliper brake. All testing of this unit was completed in a static test fixture. Test load conditions were set to simulate a flat, paved surface, with the equivalent of a 170 lb rider on board.
(Click Pics to enlarge-Use browser
"Back" to return)
|