What causes Rectifier/regulator failure, kills battery on the Triumph Bonneville T100?

Test charging voltage, look for melted wiring near unit Estimated fix cost: $150-$300

What causes Cam chain tensioner wear, rattles on startup on the Triumph Bonneville T100?

Listen for cold-start rattle, ask service history Estimated fix cost: $200-$500

Rough idle or surging at low speeds Estimated fix cost: $80-$150

Known issues to inspect before buying a used Triumph Bonneville T100. What to check and how much repairs cost.

SERIOUS

Test charging voltage, look for melted wiring near unit

Fix cost: $150-$300

MODERATE

Listen for cold-start rattle, ask service history

Fix cost: $200-$500

MINOR

Rough idle or surging at low speeds

Fix cost: $80-$150

☐Check charging system voltage at 3000rpm

☐Listen for engine rattle when cold

☐Inspect for oil leaks around rocker covers

☐Verify full service history exists

Generally solid, electrical gremlins are main concern