How to Bleed and Replace Brake Fluid on a 2015 Polaris Sportsman Touring 850 SP

Shop parts for a 2015 Polaris Sportsman Touring 850 SP ATV.

This MotoSport-exclusive guide walks you through a full brake-fluid replacement and bleed for the 2015 Polaris Sportsman Touring 850 SP. Follow every step carefully & always work safely: wear eye protection, gloves, and keep the machine on a stable lift or jack stands with the parking brake on and the key off.

What you'll need

  • DOT 4 brake fluid (Polaris recommends DOT 4-use fresh, unopened fluid)
  • Clear plastic tubing to fit bleeder nipples
  • Catch bottle and some rags
  • Wrenches (typically 8mm-10mm for bleeder nipples on Polarisverify fit)
  • Turkey baster or syringe to remove old fluid from reservoirs
  • Brake cleaner
  • Vacuum or pressure bleeder (optional but speeds and simplifies the job)
  • Shop manual or service manual for torque specs and component locations

Model-specific notes for the 2015 Sportsman Touring 850 SP

  • The Touring 850 SP uses hydraulic disc brakes with a separate master cylinder/reservoir for the front and rear circuits. Reservoir locations may be under the front cargo rack or near the handlebar area – remove covers to access.
  • This model may be equipped with EPS (electronic power steering) on some units. EPS does not change the brake-bleeding procedure, but avoid pressing or activating EPS components while bleeding.
  • Observe brake hose routing & clamps when reassembling; these units see heavy vibration and routing integrity is important to prevent chafing.
  • If your Touring has a parking brake cable for the rear, check cable operation after bleeding; improper cable adjustment can create a dragging rear brake that looks like a hydraulic problem.

Overview of the task

You will replace old fluid by: (1) removing old fluid from each reservoir, (2) topping with fresh DOT 4, (3) bleeding each caliper from the wheel farthest from the master cylinder toward the closest, and (4) repeating until clean fluid runs and no air is present.

Step-by-step procedure

1. Prepare the ATV

  • Park on level ground; secure machine so it cannot roll.
  • Remove body panels or racks as needed to access front and rear master cylinder reservoirs and bleeder nipples at each caliper.
  • Clean reservoir caps/area thoroughly to avoid contamination.

2. Remove old fluid from reservoirs

  • Use a turkey baster or syringe to remove as much old fluid as possible from each reservoir. Do not mix fluid reservoirs.
  • Wipe out the reservoir mouth with a clean, lint-free cloth and refill with fresh DOT 4 to the full mark.

3. Bleeding order

Bleed starting with the wheel farthest from each master cylinder and finish with the closest. Typical order for this ATV is:

  • Rear caliper (often farthest from front master)
  • Right front caliper
  • Left front caliper (closest)

If your unit has separate front & rear master circuits, treat each circuit independently and follow farthest-to-closest for each circuit.

4. Manual two-person bleed method

  1. Attach clear tubing to the bleeder nipple and place the other end in a catch bottle partially filled with clean brake fluid to prevent air re-entry.
  2. One person slowly depresses the brake lever/pedal while the other opens the bleeder nipple about a 1/4 turn. Fluid & air will flow into the tube. Close the nipple before the lever/pedal is released. Repeat until fluid runs clear and free of air bubbles.
  3. Top off the reservoir frequently to prevent it running dry & drawing air into the system.
  4. Work through the bleed order, and after finishing, pump the brake lever/pedal several times to check firmness. If spongy, repeat the process.

5. Single-person or vacuum/pressure method (recommended for ease)

  • Use a vacuum bleeder at the bleeder nipple or a pressure bleeder at the reservoir. Follow manufacturer instructions for those tools.
  • These methods reduce the risk of introducing air by keeping the reservoir sealed and applying steady flow from the master to bleeders.

6. Final checks

  • Ensure all bleeder nipples and reservoir caps are tightened to proper snugness (do not overtighten).
  • Clean any spilled fluid immediately – brake fluid can damage plastic and paint.
  • Dispose of old fluid properly per local regulations.
  • Test brakes at low speed in a safe area before returning to normal use to confirm pedal/lever firmness and that no dragging or pulling occurs.

Troubleshooting & tips

  • If brakes remain soft after thorough bleeding, inspect for leaking calipers, damaged hoses, or a faulty master cylinder. These will allow air back into the system or reduce hydraulic pressure.
  • Watch for collapsed or soft brake hoses on older machines — replace if bulging under pressure.
  • If you encounter persistent contamination or dark, dirty fluid after multiple cycles, a complete system flush is required — continue until clean fluid appears at bleeders.
  • Record date and miles/hours of the fluid change. Brake fluid should be changed periodically as part of preventative maintenance; store info in your service log.

Safety reminders

  • Never reuse brake fluid removed from the system.
  • Do not use DOT 5 silicone fluid unless the system is explicitly designed for it; DOT 4 is specified for this Polaris model.
  • A brake system that feels spongy or that leaks is unsafe — do not ride until corrected.

Recommended MotoSport parts & accessories

Use high-quality DOT 4 fluid and OEM-spec replacement caliper hardware, bleeder screws, and hoses when worn. If you need parts specific to the 2015 Polaris Sportsman Touring 850 SP, reference the parts catalog for fitment and OEM part numbers.

Related Shopping Categories

Shop Brake Fluid for a 2015 Polaris Sportsman Touring 850 SP ATV.

Shop Brake Bleeders for a 2015 Polaris Sportsman Touring 850 SP ATV.

Shop Brake Pads for a 2015 Polaris Sportsman Touring 850 SP ATV.

Shop Brake Lines for a 2015 Polaris Sportsman Touring 850 SP ATV.

Shop Brake Tools for a 2015 Polaris Sportsman Touring 850 SP ATV.

Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.