There’s a special kind of satisfaction that comes from wrestling a classic piece of off-road history down a muddy trail. If you’re the proud owner of a 1987 Polaris Trail Boss 250R/ES, you know exactly what we’re talking about. It’s not just an ATV; it’s a two-stroke, chain-driven time machine.
We know you agree that keeping a vintage machine like this running isn’t always a walk in the park. You’re likely dealing with worn parts, quirky starting procedures, and the ghosts of maintenance past. That’s where we come in.
At FatBoysOffroad, we promise to give you the expert, no-nonsense advice you need to keep that Trail Boss kicking. This comprehensive guide is packed with the tips and tricks we’ve learned from years in the garage and on the trail.
In this article, you’ll get a complete 1987 polaris trail boss 250r/es guide. We’ll cover its unique history, a bulletproof maintenance checklist, how to troubleshoot the most common problems, and even some best practices for riding your classic quad responsibly. Let’s get those knuckles greasy.
Understanding Your Vintage Beast: What Makes the Trail Boss 250R/ES Special?
Before we dive into the nuts and bolts, let’s appreciate what you’ve got. The 1987 Trail Boss was a game-changer. It was one of the early ATVs that helped solidify Polaris as a major player in the powersports world. It’s a bridge between the sketchy three-wheelers of the past and the complex 4x4s of today.
The “R/ES” designation stands for Reverse/Electric Start, which were premium features back in the day. This machine was built for utility and fun, with a simple but rugged design that’s easy for a DIY mechanic to work on.
Key Specifications and Features
Knowing the core of your machine is the first step in any good 1987 polaris trail boss 250r/es care guide. Here’s a quick rundown of what makes it tick:
- Engine: A reliable 244cc, single-cylinder, two-stroke, fan-cooled engine. It’s simple, powerful for its size, and delivers that classic two-stroke “braap.”
- Transmission: Polaris Variable Transmission (PVT) with Forward, Neutral, and Reverse. This automatic system was revolutionary and made the ATV accessible to more riders.
- Drive System: A straightforward and durable chain drive system powers the rear wheels.
- Brakes: It typically featured hydraulic disc brakes, offering decent stopping power for its era.
- Starting System: The coveted electric start (ES) backed up by a good old-fashioned recoil pull-starter for when the battery gives up the ghost.
The beauty of this ATV is its simplicity. There are no complex electronics, no fuel injection computers, and no power steering modules to fail. It’s pure, mechanical fun.
The FatBoysOffroad Pre-Ride Checklist: Your Essential Care Guide
Never just hop on and go, especially with a vintage machine. A thorough pre-ride inspection can be the difference between a great day on the trails and a long walk back to the truck. This is one of the most important 1987 polaris trail boss 250r/es best practices we can share.
Run through this checklist every single time you ride. We call it the “T-CLOCS” method, adapted for our classic quads.
- Tires & Wheels: Check the air pressure. Look for cracks in the sidewalls and ensure no lug nuts are loose. An underinflated tire is asking for trouble.
- Controls & Cables: Squeeze the brake levers. Do they feel firm or spongy? Operate the throttle; it should snap back cleanly when released. Check the shifter and reverse lever for smooth operation.
- Lights & Electrics: Test the headlight and taillight. If you have the electric start model, make sure the battery has a good charge. A weak battery can leave you stranded.
- Oil & Fuel: This is a two-stroke, so your oil is mixed with your gas. Always use a high-quality two-stroke injector oil. Check your fuel level and ensure there are no leaks from the tank, fuel lines, or carburetor.
- Chassis & Suspension: Give the ATV a good shake. Check for loose bolts on the suspension, handlebars, and frame. Inspect the chain for proper tension—it should have about 1/2 to 3/4 inch of slack.
- Safety Gear: This isn’t on the quad, it’s on you. Helmet, gloves, boots, and goggles. No exceptions.
Common Problems with 1987 Polaris Trail Boss 250R/ES and How to Fix Them
Every old machine has its quirks. After spending countless hours on these, we’ve seen it all. Here are the most common problems with 1987 polaris trail boss 250r/es and the garage-tested solutions.
Problem 1: It Won’t Start or is Hard to Start
This is the number one issue. The cause is almost always related to one of three things: fuel, spark, or air.
- Fuel Issues: The carburetor is your most likely culprit. Old fuel turns to varnish and clogs the tiny jets inside. The fix is a thorough carb clean. You’ll need a can of carb cleaner, some small brushes, and patience. Disassemble it, clean every jet and passage, and reassemble with a new gasket kit.
- Spark Issues: Pull the spark plug out, connect it back to the plug wire, and ground the threads against the engine. Crank it over. You should see a strong, blue spark. If you see a weak, orange spark or no spark, start by replacing the NGK B8ES spark plug. If that doesn’t work, you may need to inspect the ignition coil or stator.
- Air Issues: Check the air filter. A dirty, oil-soaked filter will choke the engine. Clean it with filter cleaner or replace it if it’s falling apart.
Problem 2: The ATV Bogs Down or Lacks Power
If your Trail Boss starts but falls on its face when you give it gas, you’re back to the same suspects, just with a different focus.
- Clogged Carb Main Jet: The main jet delivers fuel at higher RPMs. Even a partial clog will cause it to bog down. A carb clean is your first step.
- Exhaust Obstruction: Two-stroke exhausts can get clogged with carbon over time. In extreme cases, a mouse may have built a nest in there! Remove the exhaust and check for blockages.
- Worn PVT Clutches: The primary and secondary clutches of the transmission wear out. If they aren’t engaging properly, you’ll lose power to the wheels. This is a more advanced job and may require special clutch puller tools.
Problem 3: Spongy or Non-Existent Brakes
Don’t even think about riding with bad brakes. The hydraulic system on these old ATVs is simple but requires maintenance.
The most common issue is old, contaminated brake fluid or air in the lines. The solution is to bleed the brakes. You’ll need a bottle of DOT 3 brake fluid, a clear hose, and a wrench that fits the bleeder valve. Attach the hose to the bleeder, have a friend pump and hold the brake lever, and open the valve to let the old fluid and air escape. Repeat until you see clean, bubble-free fluid. If the master cylinder or caliper is leaking, you must rebuild or replace it.
How to 1987 Polaris Trail Boss 250R/ES: Key Maintenance Procedures
Beyond the pre-ride check, regular maintenance is key to longevity. Here’s a deeper look at a few critical tasks. This is the core of any good 1987 polaris trail boss 250r/es tips collection.
Servicing the Chain Drive
Your chain takes a beating. Neglect it, and it will leave you stranded.
- Cleaning: Use a stiff brush and a dedicated chain cleaner to scrub off all the old gunk and grime.
- Lubricating: Once clean and dry, apply a high-quality chain lube specifically for off-road use. These are designed to stick to the chain and not fling off.
- Adjusting: Find the tightest spot in the chain. At the midpoint between the sprockets, you should have about 1/2 to 3/4 inch of up-and-down play. Loosen the rear axle carrier bolts and use the adjuster bolts to get the tension right. Make sure the axle is straight before tightening everything back up.
Two-Stroke Oil System Care
Your engine’s life depends on that two-stroke oil. The Trail Boss uses an oil injection system, which is convenient but needs to be checked.
Ensure the oil tank is always filled with a quality two-stroke injector oil (not pre-mix oil). Periodically check the oil line from the tank to the oil pump and from the pump to the carburetor intake. If it looks cracked, brittle, or yellowed, replace it immediately. An oil line failure will starve the engine of lubrication and cause a catastrophic failure.
Sustainable Riding: Eco-Friendly Tips for Your Vintage 2-Stroke
Owning a classic two-stroke doesn’t mean you can’t be a responsible steward of the trails. A sustainable 1987 polaris trail boss 250r/es is all about minimizing your impact.
The best thing you can do is ensure your machine is in perfect running order. A well-tuned engine burns cleaner and more efficiently, producing less smoke and unburnt fuel. Fix any fuel or oil leaks immediately to prevent them from dripping onto the trail.
An eco-friendly 1987 polaris trail boss 250r/es approach also means using the right products. Modern two-stroke oils are formulated to burn much cleaner with less smoke than the oils available in the 80s. When you wash your quad, use a biodegradable soap and avoid letting soapy runoff enter storm drains or waterways.
Frequently Asked Questions About the 1987 Polaris Trail Boss 250R/ES
What is the fuel to oil ratio for a 1987 Polaris Trail Boss 250?
If the oil injection system is working correctly, you don’t need to pre-mix the fuel. Just keep the oil reservoir full with a quality two-stroke injector oil. If you’ve removed the injection system for a pre-mix setup, a 40:1 ratio (3.2 ounces of oil per gallon of gas) is a safe starting point. Always use a high-quality synthetic two-stroke oil.
How fast does a 1987 Polaris Trail Boss 250 go?
Top speed on a stock, well-maintained 1987 Trail Boss 250 is typically around 40-45 mph. Speed can vary based on rider weight, terrain, and the condition of the engine and clutch system.
Are parts still available for a 1987 Polaris Trail Boss 250?
Yes, but it takes some searching. Many common maintenance parts like spark plugs, air filters, and brake pads are readily available from aftermarket suppliers. However, model-specific parts like plastics or certain engine components may require searching eBay, ATV forums, or salvage yards. Don’t be afraid to get creative!
Keeping a classic like the 1987 polaris trail boss 250r/es on the trail is a rewarding journey. It teaches you patience, problem-solving, and the fundamentals of how these awesome machines work. Every bolt you turn and every problem you solve connects you more deeply to the ride.
Use this guide as your starting point, trust your instincts, and don’t be afraid to ask for help. Now get out there, stay safe, and have a blast making new memories with your vintage beast!
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