Assault AirBike, How to Replace the Long Chain, Hub to Fan, Left Side

Learn how to replace the long chain on your Assault Air Bike. The long chain is on the user's left side of the bike. The chain connects the large hub sprocket and the fan sprocket. The steps to replace the chain are the same for the Classic, Pro, and Elite Assault bike models.

Part Discussed:

• Left Hand Chain with Master Link, Long - OEM part 23-AS-025 or OEM part 23-AS-397

Tools Needed:

• 8mm Allen Wrench
• 15mm Ratchet Wrench
• 10mm Ratchet Wrench
• Rubber Mallet
• Phillips Screwdriver
• Needle Nose Pliers
• Crank Puller (22mm)
• Crescent or Adjustable Wrench

Procedure:

1. Using the 8mm Allen wrench, remove the crank-fixing bolt from the left bell crank arm assembly. If the bolt is stubborn, gently tap the Allen wrench with the rubber mallet until the bolt is loosened.
2. Thread the crank puller into the crank arm and firmly tighten the top section using the crescent or adjustable wrench. First time using a crank puller? Watch our video about how to use a crank puller. Note: If you do not tighten the tool enough, the threads tend to strip and will ruin your tool or crank arm, if not, both.
3. Using the crank arm for support, loosen the bottom section of the crank puller with the crescent wrench. If your crank puller has a built-in handle, you will turn the handle on the tool towards the right. This tightens the crank puller against the crank. As you continue to turn the handle, it pulls the arm free from the shaft.
4. Separate the crank assembly from the bike.
5. Using the Phillips screwdriver, remove the 4 screws holding the chain guard in place.
6. Slide the chain guard toward the back of the bike and remove the chain guard.
7. Remove the fan guard cover from the left side of the bike.
8. Using the Phillips screwdriver, remove the speed sensor bracket from the right side of the fan.
9. Slide the speed sensor away from the right fan cage cover.
10. Remove the fan cage cover on the right side of the bike.
11. Using the 15mm ratchet wrench loosen the acorn nuts on both sides of the fan axle.
12. Before replacing the chain, loosen the chain tensioner nuts on both sides of the fan wheel using the 10mm ratchet wrench.
13. Rotate the left chain until you identify the master link.
    
14. First, remove the spring clip off the master link using the needle nose pliers.
    
15. Next, remove the remaining pieces of the master link from the chain. Remove the flat plate and the backer plate with pins.
16. Remove the chain.
17. Feed the new chain around the drive cog and the chain wheel.
18. Join the new chain with the backer plate and fasten the flat plate to the front of the chain. Install the spring clip. Reverse of how you removed the master link.

      Tech Tip

    Use the teeth of the chain sprocket to hold the ends of the chain while installing the master link.

19. Carefully re-install the chain guard by sliding it on.
20. Using the Phillips screwdriver, tighten the 4 screws of the chain guard in place.
21. Re-attach the bell crank assembly making sure the crank arms are opposite of each other.
22. Using the 8mm Allen wrench, screw the crank-fixing bolt into the bell crank assembly.
23. Equally, tighten the chain tensioner nuts on both sides of the fan wheel using the 10mm ratchet wrench. Ensure the chain stays straight.
24. Confirm the new chain is rotating in a straight line around the drive cog and chain wheel.
25. Check tension by lifting on the chain. The proper tension for the long chain is 1/2" of movement. Adjust the position of the chain tensioner nuts, equally, on both sides of the fan wheel for proper chain tension.
26. Tighten the acorn nuts on both sides of the fan axle using the 15mm ratchet wrench.
27. Re-install both fan cage covers.
28. Re-install, align and tighten the speed sensor bracket using the Phillips screwdriver.
29. Check the operation of your bike to ensure all parts are working as expected.