The ad falsely states that it is made in the U.S.A. It is completely manufactured in China. It should be judged from the perspective of its bottom dollar retail price (currently $25.49). It is NOT a robust piece of equipment designed for a working life of 150+ hours of fitness usage. No, it is a disposable machine that is marketed for a working life of only about 7-10 hours of light physical therapy spread out over several weeks. Afterward, the user should expect to throw it away. Next to its aesthetically simple, light weight design, its 2nd most desirable feature is its digital console. Unlike nearly all other fitness machines, it employs a nifty Hall effect motion sensor, which obviates the need for a permanent magnet. I checked it for accuracy: Cranking the machine exactly 100 revolutions, it displayed a count of 100. Note: If your console is displaying but is stuck (not counting or timing), then the likely fault is failure of the hot melt glue to bind the sensor in place (within its rectangular clearance hole). I solved that problem by peeling off the glue, reinserting the sensor, and then shimming tight the hole clearance gap with a pair of 1/2" long wooden splinters (actually, soft wedge-shaped Stim-U-Dents). You can easily pop the console out of its housing to inspect the disposition of the sensor inside. The spindle is problematic, mainly because it lacks ball bearings or metallic bushings. There is a pair of interlocking plastic (probably nylon) half-bushings at each end of the housing. Each half-bushing has bore 7/16" x length 1¼". Each pair interlocks snugly only when the resistance bolt is making at least slight pressure on the axle. During a workout, that resistance bolt must not be loose or missing. Otherwise, the bushing-halves drift apart, which greatly exacerbates their wear. No doubt this explains why users who did not receive a friction bolt observed their machines rapidly fall apart. I adjusted the resistance bolt snugly; NOT with maximum hand torque. That was enough to produce significant fatigue of my triceps while arm cycling @ 120 rpm for only 90 secs. Immediately afterward, I felt with my index fingers the exposed segments of the axle where they protrude from the housing. Much to my dismay they had already become warm to the touch. Heat is due to friction... Not only is there friction between the resistance bolt and axle, the other source is between the axle and the two lower half-bushings. This is because the the bolt force pushes the axle downward to bear against those two lower half-bushings. Keeping in mind that the half-bushings are cheaply made of plastic, it is unwise to apply more torque to the friction bolt than is required to eliminate play between the axle and the bushing sets. So applying excessive torque to the hand knob is just as bad for the life of the machine as operating the machine with that bolt loose. Conversely, almost as bad for the bushings is leaving the hand knob tight whenever the machine is NOT in use. Why? The plastic half-bushings will be subjected to 'creep deformation' arising from the continuous stress from the bolt. Eventually an ever-present stress will cause the bushings to cold flow to a permanent shape that is not cylindrical enough for good functioning. So whenever the machine is not being used, remember to keep the bolt loose. During an exercise session, the bolt should be retightened with only enough torque for snugness. The plastic handles/pedals are the worst I've ever seen. They have no ball bearings, not even any bushings; just sloppy clearance fits with the diametral dimensions of internal washers! Consequently the excessive play makes an annoying click-clack noise. Here is where the Marcy NS-909 (mechanically identicle to Sunny 030) is clearly superior, as its handles/pedals contain ball bearings. Unlike this machine, the Marcy NS-909 has NO friction bolt pressing against its axle. Instead, it has a proper method of resistance utilizing a friction strap rubbing against a cast iron flatbelt pulley. As a leg bike, I have found that neither this machine nor the Marcy NS-909 is useful for either cardio-respiratory fitness or calorie burning. They cannot possibly function as fitness machines when operated by the LEGS; grossly unsuitable for that purpose. This is partly because the motion circle is only 8" dia (compared to 12.5" for a recumbent bike), and maximum torque resistance is unnoticable by a normal individual's thigh muscles. However, if the intended use is gentle therapy for blood circulation or range of motion, then either model could function OK, albeit BRIEFLY, considering their cheap crank axle bushings. Best leg utility is EARLY rehab therapy for those who are recovering from a broken ankle/leg, or a hip/knee replacement, heart surgery, lymphodema, diabetic leg swelling, etc.. Note that for leg cycling, when the resistance is properly set (see above), the machine tends to wander about the floor (either hard flooring or carpeting). The solution is to butt its farthest cross-member up against the room wall's baseboard trim. That traps the machine in place. It works far better as an ARM bike. If you place it atop a kitchen counter, laundry washer, laundry drier, or a very heavy, rigid table, then you can cycle away as fast as you can, and it will stay put. The reason why the machine doesn't crawl about while you work it via your arms is because while one arm pushes, the other arm pulls, thereby equalizing the forces and stabilizing its position. I placed it on the top of our staircase, knelt onto a cushion placed 3 stair-steps below, and then did 12 x 30-sec SPRINT INTERVALS alternated with very slow 20-sec active recoveries. Not only did I work up a SLIGHT sweat, but it caused my tricep muscles to fatigue considerably, despite regular weight lifting at my local gym. I've since discovered that when the machine is atop of our top-loading laundry washer the arm cycling ergonomics are improved enough to enable work in the reverse direction of rotation. So now I alternate my arm sprint intervals in order to spread the burden more evenly on the muscle groups. Although its handle centers revolve about a diameter of only 8", I discovered how to exercise my entire 23" reach with this machine. Using only a braided nylon cord (1/8" dia x 60" len) I hung the machine from two corners of a bathroom door. Then, after latching shut the door I varied my arm cycle intervals via 3 different torso distances from the machine: close, mid-range, and maximum. Maximum speed from a standing position was challenging, and could thus be useful for training boxers and mixed martial artists. Anyone who is interested in doing 1-3 mins of arm warmup exercise just prior to a heavy weight lifting session should consider getting one of these machines. It's worth it just for that purpose, as it could help prevent an injury. I've suffered from elbow tendonitis and from shoulder impingements, so you can understand my special interest in this machine.
