Simply constructed, with no controls available and no rider decisions involved, this scheme works well, up to a point. However, full-time four-wheel drive arrangements always produce ground-slip, increasing steering resistance, stressing drivetrain components, and wearing tire tread, because the front wheels cover different distances than the rear ones when making turns.

Further, full-time four-wheel drive limits the rider's ability to power-slide, to use the throttle along with the handlebars, aiming the quad around a high-speed turn.

Until now, 2WD/4WD capability existed only on quads with factory-installed controls and linkage, permitting the "best of both worlds;" 4WD when needed, and 2WD when desired.

Enter High Lifter's Detroit UN-Locker: a replacement front driveshaft with an "unlockable" coupling, providing selectable 2WD/4WD to any quad so equipped. Unveiled at this year's Indianapolis ATV trade show, the product drew lots of "Why didn't WE think of that?" comments, even from ATV manufacturers.

High Lifter had a prototype UN-Locker installed in a Honda Foreman 450ES sitting on the concrete apron of the shop area of their new headquarters, when I stopped by to visit.

I decided on a "before" and "after" comparison, even riding for a short distance on concrete, where the most severe consequences of front-rear wheel travel mismatch occur. The test Honda 450ES provided an opportunity for great contrast, thanks to its lift kit and its humongous 28" Outlaw tires. In tight turns on pavement, the four-wheel drive configuration performed as expected; lots of steering force required, some cries for mercy from the tire tread, U- and CV-joints, and the geartrain. Stopping, I followed the High Lifter technicians' instructions, unlocking the front end. I twisted the control cable T-handle 90 degrees, freeing it, and pulled the control to the rear "unlocked" position; then, turned the T-handle 90 degrees, again securing the control knob in its new position. The cable slid smoothly in its sheath, traveling to a definite en, turned the T-handle 90 degrees, again securing the control knob in its new position. The cable slid smoothly in its sheath, traveling to a definite "stop."

This simple transition from 4WD to 2WD takes less time to perform than to tell about it, possible "on the fly," when riding conditions change.

Following the same curved path just traveled, I felt a dramatic difference from the first wheel turn. Steering was light, handling crisp; no more complaints from tire scrape or drivetrain binding, even on dry concrete. The Foreman instantly behaved like the creature it had just become: a 2WD quad!

High Lifter designers chose a manual cable control system for the UN-Locker for simplicity, reliability, and cost considerations. While a solenoid control arrangement was considered, the cost and complexity were not justified, given the expected frequency of use. Also, harsh mud and water environmental exposure in the control mounting area favored a mechanical, instead of an electrical, solution.

The UN-Locker is essentially a two-piece driveshaft, the halves connected by a center coupling. An external ring on the coupling exterior rotates inside a notch cut in a Phenolic (industrial plastic) block, attached to the control cable. When the cable is pulled, the Phenolic block forces the coupling forward, unlocking the two driveshaft halves, disconnecting the front differential from the drivetrain. A teflon center inside the coupling separates the driveshaft halves.

The cable control knob sits within easy reach of the rider's left hand; the cable runs forward, through an existing hole in the front plastic, and down to a mounting bracket near the coupling in the center of the replacement driveshaft. The production model kit uses existing holes for mounting the lower cable bracket; the upper, control end cable bracket mounts to the front rack, requiring no holes in the plastic.

High Lifter chose Trac Tech, Inc., the prominent aftermarket auto and truck drivetrain component (including the famous Detroit Locker) manufacturer, to produce the UN-Locker.

High Lifter plans initially releasing UN-Locker kits for Honda 450's, with setups for 500's, 350's and 300's soon to follow. Kits for additional models will be added. All kits include detailed installation instructions and necessary hardware.

Besides unlocking the front end, I believe the High Lifter Detroit UN-Locker will unlock the racer, the sport quad rider image, in its users.

We'll find out, when a production model UN-Locker becomes available for a thorough ATV Magazine/Paatving.com product evaluation. Stay tuned!

UN-Locker will be available for the Honda 450 in Early July, list price $449.00.

Ordering Information