Henter Wheel Aligner
Henter Wheel Aligner
EVALUATION
Everyone knows that the wheels should be aligned on the family car because misalignment shows up as unusual tire wear. Alignment of motorcycle wheels is actually more critical, yet less obvious and more often overlooked.
Most riders don’t worry about wheel alignment and those who do usually count on the stamped marks on the swing arm. But because of manufacturing tolerances, the swing arm marks may not be accurate, and even a slight error at the marks can have the rear wheel out of line with the front wheel by several degrees.
With the wheels misaligned by only 2°. the bike’s rear wheel will try to kick out to one side under heavy braking or acceleration. Stability can be affected not only during acceleration and deceleration, but also during steady throttle cruising. With a given amount of power transmitted through the rear wheel to maintain a speed, part of that power will be stored in the frame through torsional loading.. Hitting a bump or even a sidewind-induced direction change can unload the chassis and start an oscillation or speed w-obble.
The quickest and most accurate method we’ve seen to check wheel alignment is the Henter Wheel Aligner. The Henter Aligner has two units, one for each w heel. Each unit is comprised of two frames, an inner and an outer. The inner frame has an open side which is slipped around the wheel and lifted up to surround the tire. The weight of the outer frame puts pressure through the inner frame to four contact points on the tire. The outer frame is then placed parallel to the ground and a pivot knob tightened up to lock the outer frame in place.
The pivot point is then in the center of the tire tread and the sighting rod is 10.5 in. from the centerline of the tire. With both alignment tools installed on the w-heels, the rider or mechanic goes to the front of the bike and turns the forks until the sighting pins of the front frame align w ith the center pin on the rear frame. The front wheel must be kept in that position, so the operation should be done w ith the bike on the centerstand or with someone holding the front of the bike.
Once the front w heel is lined up with the rear w heel, the mechanic goes to the rear of the bike and sights down the three pins on the rear tool. Using the axle adjusters, the rear wheel is adjusted so that all of the pins line up. Once chain slack is rechecked and the axle nut tightened, the job’s done.
Even if the alignment marks on your bike's swing arm are accurate, the Henter tool is more precise because of the distances involved. A 2° misalignment of the rear wheel may be only a difference of 0.020 in. at the adjustment marks, but the alignment tool multiplies that difference to an easily-visible 1.6 in. at the front alignment frame. You're still using a sighting method, but because of the geometry involved. small errors are more obvious.
We tried the Henter Wheel Aligner on a brand-new test bike. The machine hadn’t been touched since delivery from the manufacturer, and the rear wheel was aligned perfectly according to the swing arm marks. Yet the Henter tool revealed that the rear w heel was out of line and cocked to the right by a little less than 1 °. showing up as 0.5 in. at the front alignment frame. That’s enough of a misalignment to make a difference.
The tool’s end lugs are aluminum castings with machined inside surfaces. The lugs are then installed in a hardened drill jig to ensure perfect spacing and alignment on the rod holes. The inside frame, which hangs on the wheel, is made of 6061-T6 aluminum rods of 0.840-in. diameter. The outside sighting frame is made of solid steel rods. To make sure that the tubes lay parallel, they are placed in v-blocks and lugs pressed on with Loctite 680 retaining compound. To improve parts bonding, the end lugs are acid etched beforehand.
In addition to aligning w-heels. the Henter Wheel Aligner can be used to determine whether a bike's frame and swing arm are twisted out of alignment by switching the frames side to side. Misalignment is indicated if one of the sighting rods is at an angle other than parallel to the ground. The tool won’t tell you w-hieh is bent—be it frame or swing arm—only that one is bent relative to the other.
Ted Henter guarantees the tools and w ill repair or replace them free of charge w ithin a year of purchase if anything goes wrong because of material or workmanship. If they are accidentally damaged, such as being run over, the only charge will be for repair material and shipping—no labor charge.
The frames should be treated as the precision instruments that they are. and Henter recommends that they be stored by hanging the solid steel rods on hooks or in a wooden storage case available for $35 from Henter.
At $125, the Henter Wheel Aligner may seem expensive for the individual who would only use the tool tw-o or three times a year. But helmets and a set of tires nowcost as much in many cases. The Henter Wheel Aligner is a valuable tool for the racer or street rider who wants his bike to be right.
From Henter Enterprises. 4651 62nd Ave. North, Pinellas Park, Fla. 33565. (813) 522-2961. 0
A promising young road racer, Ted Henter. set off to make his mark in Europe after finishing fourth in the 250 race at Daytona 1979. Unfortunately. an untimely traffic accident in England left him blind.
Henter returned home to Florida and put his engineering schooling to good use by inventing and developing the Henter Wheel Aligner, a device he had visualized two years ago. Henter Enterprises was formed to market the tool.
