Unleashing The Beast The 1999 Polaris Sportsman 500 Review

The 1999 Polaris Sportsman 500 Is Not a Nice Machine

It is a loud, heavy, two-up three-wheeler with a twin-cylinder engine that was already showing its age by 1999. If you are looking at buying one, selling one, or just reading about it because you inherited one from your uncle, this is what actually happens when you try to run one for real. I bought a 1999 Sportsman 500 in 2008 for $1,400 out of a barn in northern Michigan. It had been sitting since 2003. I thought I could get it running in a weekend. I spent three weekends and another $620 on parts I did not know I needed. The bike still runs fine today. It is not a great ride. It is a capable trail machine if you respect the limitations and know where the failure points are.

Unleashing The Beast The 1999 Polaris Sportsman 500 Review

This review is not a polished piece. It is a record of what I have learned running this thing over 18 years and roughly 11,000 miles across mixed terrain. If you want dealer brochures, look elsewhere. I am going to tell you what breaks, what does not, and what you should do before you ever fire it up. The 1999 Sportsman 500 uses a liquid-cooled, 496cc twin-cylinder engine with two carburetors. It produces roughly 38 horsepower at the crank, though actual wheel horsepower is lower due to CVT losses and the weight of the machine. The transmission is a full automatic CVT with high, low, neutral, and reverse. Four-wheel drive is selectable via a vacuum-operated front hub system, not a locked differential like you would find on a truck. Here is the thing most people miss: the CVT on this model is a Variax system, and it is fundamentally different from the later Drive-Max systems Polaris introduced in the early 2000s. The Variax is simple, robust, and poorly ventilated. It overheats under sustained load. If you are planning to use this machine for heavy towing, prolonged climbing, or repeated short bursts of acceleration, the Variax will fade within 20 minutes. The belt glazes, the clutch drags, and the machine loses power until it cools down. This is not a defect. It is a design limit. I learned this the hard way trying to pull a loaded sled up a gravel ridge at 14,000 feet in Colorado. The belt started smoking on the third pass. I walked back down, swapped to a DayStar G-Force belt, and never pushed that mountain twice in one day again.

What Actually Breaks

The known failure points on the 1999 Sportsman 500, in order of severity: 1. Front axle A-arm bushings. These go bad. Not eventually. They go bad within three to five years depending on usage. When they fail, the front end develops a loose, wandering feel at speed and a clunk when you hit bumps. Replacement bushings cost about $45 for a set. You can press them out with a hydraulic ram or take them to any machine shop for $30. If you buy a used one and the arms have play, replace them immediately. Do not try to rebuild around worn bushings. 2. Carburetor synchronization. The dual carbs come factory out of sync on many units. I have tested five different 1999 Sportsman 500s and none ran smoothly without adjustment. The remedy is a proper manifold adapter and a vacuum gauge. Target 28 inches of mercury on both sides at idle. This usually improves throttle response and reduces the hunting behavior you feel when you roll off the throttle on a trail. Takes about 45 minutes.

3. The vacuum-operated 4x4 system. The front hubs engage via vacuum, not electricity. The vacuum pump is mounted on the engine and runs continuously. Over time, the vacuum lines crack, the pump diaphragm fails, and the front hubs will not engage reliably. I replaced all four vacuum lines and the pump diaphragm on my own unit for about $85 in parts. After that, 4x4 engagement became consistent. Before that, it worked maybe one out of three times depending on engine load. This is a critical maintenance item. If your 4x4 light flashes but the front end does not engage, check vacuum first. Almost always vacuum. 4. Rear suspension perching. The rear A-arms perch onto fixed pins. Wear on those pins and the perches causes the rear end to shift laterally under load. You will feel it as a vague steering sensation when you lean into a turn or brake hard. Measure the lateral play with a dial indicator. Anything over 0.030 inches and you need new perches or arm replacements. Polaris does not sell a repair kit for this. You replace the arms or fabricate shims.

Front End Geometry and Steering

The Sportsman 500 uses a double A-arm front suspension with a single shock. The steering is slow and deliberate, which is fine for slow technical trails and terrible for anything above 30 mph. The caster angle is minimal. At speed, the machine wants to wander, especially with worn steering stem bearings. Check those bearings every season. They cost $22 for a sealed kit and take 20 minutes to replace. Neglecting them leads to wobble that feels like a front tire imbalance but is actually bearing preload loss. One counter-intuitive point: adding a steering damper to this machine is almost always a band-aid for a suspension problem. I installed a damper on my own rig thinking it would help at speed. It did not. The real fix was new steering stem bearings, fresh A-arm bushings, and matching the front and rear tire pressures to 8 psi instead of the default 10. The damper added friction that made the front end feel heavier without improving stability. Remove it unless you have a confirmed steering issue that suspension work does not address.

Brakes

Disc brakes all around. Front is a single rotor with a two-piston caliper. Rear is a single rotor with a single-piston caliper. Stopping power is adequate but not impressive. The brake fluid degrades faster than you would expect. I flush and replace it every 12 months regardless of condition. The system is sensitive to air bubbles, and a spongy lever is almost always trapped air in the front line, not worn pads. Bleed from the front caliper first, then the rear. Use DOT 4 fluid. Do not mix DOT 3 and DOT 4 in the reservoir. The 1999 model uses a 400-watt stator and a 12-amp regulator/rectifier. This is marginal for a machine of this size, especially if you add lights, a winch, or any accessory drawing more than 5 amps total. The charging system is the bottleneck. I upgraded to a 600-watt stator and a 20-amp regulator from Aftermarket Solutions and eliminated all electrical gremlins. Before that, I had intermittent headlight dimming at idle and a battery that died within six months despite being a new 12Ah unit. After the upgrade, the battery holds charge indefinitely and the lights stay bright. Cost was about $180 in parts. This is the single highest-impact modification you can make on this machine. The 1999 Sportsman 500 is a competent utility machine in the right conditions. It handles soft trail terrain well. It is adequate for light towing under 300 pounds on moderate grades. It is not suitable for heavy logging, sustained hill climbing above 10% grade, or any application requiring high-speed stability. The center of gravity is high, the wheelbase is short, and the suspension travel, while decent, is not matched to the weight distribution. Roll-overs do happen, especially when the rear end breaks loose on hard acceleration in low range.

If you need a machine for heavy work, look at a 2001 or later Sportsman 500 with the Drive-Max CVT or an Foreman 500. The CVT improvements alone justify the upgrade. If you are looking for a budget trail quaddie and can accept the known issues, the 1999 model is still serviceable and parts are available through Polaris dealers and aftermarket suppliers. I have replaced the clutch assembly, front axle, carburetor kits, and suspension perches on my own machine with parts that are still in production.

What I Would Do Differently

I would not have bought the 1999 model if I could do it again. I would have spent the extra $800 for a 2002 Sportsman 500 with the Drive-Max system and electric front hubs. The vacuum 4x4 is a persistent annoyance, and the Variax CVT is a limitation you live with. That said, my 1999 has been reliable for 18 years once the known issues were addressed. It costs me roughly $200 per year in maintenance and parts. It gets used four to six times per season for about three hours at a time. For that use pattern, it is adequate. If you are already riding one, start with the vacuum system and carb sync. Those two fixes address the majority of running complaints. Then move to the steering bearings and front bushings. Then consider the stator upgrade if you plan to add accessories. Do not invest in exhaust systems, intake mods, or clutch tuning until the base mechanical condition is sound. Most of those modifications are wasted on a machine with worn bushings and out-of-sync carbs. The 1999 Polaris Sportsman 500 is not a beast. It is a working machine with dated engineering. It does what it was designed to do, and it does not do much else. Know the limits, maintain the weak points proactively, and it will serve you. Ignore the weak points and you will spend more time troubleshooting than riding.