If you have DRUM brakes:
The adjustment is typically done via a cable adjuster located near the rear brake lever and a star-wheel adjuster within the drum itself. You'll need to:
1. Locate the cable adjuster: This is usually a small, knurled nut or bolt near the point where the brake cable attaches to the rear brake arm. Loosen this adjuster first to give you some slack.
2. Access the star wheel adjuster: This requires removing the brake drum. This often involves removing the wheel, then finding and removing the retaining nuts or screws holding the drum in place. *Be careful; the springs inside the drum are under tension.*
3. Adjust the star wheel: Once the drum is removed, you'll see a star-shaped adjuster. This is rotated to increase or decrease brake shoe contact with the drum. Turn it clockwise (usually) to tighten the brakes, counterclockwise to loosen. Make small adjustments and reassemble the drum to test. You want just enough adjustment so the shoes lightly contact the drum, but not enough to cause dragging.
4. Reapply the cable tension: After you've adjusted the star wheel, tighten the cable adjuster until the free play at the pedal is roughly 1/4 to 1/2 inch. Test the brakes.
5. Reassemble everything: Put the brake drum back on, and secure the wheel.
If you have DISC brakes:
Disc brake adjustment is typically not user-adjustable in the same way drum brakes are. The adjustment is typically done automatically by the caliper pistons when you apply the brakes. If your rear disc brakes feel weak, the problem may be:
* Low brake fluid: Check the level in the master cylinder reservoir.
* Worn brake pads: Inspect the thickness of the brake pads.
* Air in the brake lines: Bleed the brakes (this requires a helper and the proper tools).
* A seized caliper: This is a more complex problem requiring more detailed inspection and possibly repair/replacement.
Important Considerations:
* Safety: Always use jack stands when working under a vehicle. Never rely solely on a jack.
* Tools: You'll need the appropriate wrenches, sockets, and possibly a brake drum remover tool.
* Manual: Consult a workshop manual specific to your 1998 Triumph Bonneville for detailed diagrams and procedures. This will be essential for accurate adjustments and safe removal and reassembly of components.
* Professional Help: If you're uncomfortable working on your brakes, take it to a qualified mechanic. Brake adjustments are relatively simple on drum brakes, but incorrectly adjusted brakes are a serious safety hazard.
Remember, these instructions are general guidelines. Always consult your bike's service manual for precise procedures and safety precautions specific to your model. Improper brake adjustment can lead to dangerous braking performance.
