Night delivery run with a worn rear tyre
You ride a light quadricycle for a courier company and finish a shift at 22:30. Before leaving the depot you notice the rear-right tyre looks low and the tread shows a shallow pattern in the centre, though you cannot measure the depth precisely. The headlight works on dipped beam, but the right indicator flashes noticeably faster than the left. Rain has just stopped and the asphalt is still wet and reflective. Your route home is 14 km, mostly on a two-lane road with no street lighting for the last 5 km. You are tired after nine hours of stop-start deliveries, and a colleague offers to follow you closely with hazard lights on to "guide" you through the dark section. The vehicle documents are in order and the compulsory insurance is valid.
1. Should you set off as planned? Identify the equipment defects and explain how the law and safe practice apply to each before the journey.
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Setting off as planned is not acceptable. Two defects are visible and both matter under the technical-condition rules.
Tyre. A tyre that looks low and has a shallow centre tread is suspect. Bulgarian rules require tyres to have adequate tread depth and correct pressure; a worn or under-inflated tyre lengthens braking distance, especially on wet reflective asphalt, and can overheat and fail at speed. You cannot verify the depth, so the correct judgement is not to ride on it: check the pressure with a gauge and measure the tread, and if it is at or near the legal minimum, replace the tyre before departure. Riding on a known suspect tyre can also breach the insurance conditions if a defect contributes to a crash.
Indicator. A fast flash on one side usually means a bulb or connection fault on that side. Direction indicators must function correctly; a faulty one reduces your visibility to other road users and is a defect you must not ignore. Fix the bulb or connector before riding.
Headlight. Dipped beam is present, which is the minimum for the dark section, but confirm the beam is correctly aimed and that the rear position light and brake light work.
Fatigue and the colleague. A nine-hour shift with stop-start work leaves you tired; fatigue is a major crash factor. The colleague following closely with hazard lights does not make the dark section safe and may distract or dazzle you. Better to fix the defects, and if you are too tired, postpone the ride or use another means of transport. The documents being valid does not cure a mechanical defect.
2. If you decide to ride after repairs, how should you adapt your riding for the wet, unlit final 5 km, and what should you do about the colleague's offer?
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After the tyre and indicator are fixed, adapt to the conditions rather than to the schedule.
Speed and sight distance. On wet reflective asphalt at night, ride so that you can stop within the distance you can see to be clear. On unlit road that means a speed well below the dry-road limit, using dipped beam and looking for the edge line and any reflective markers. Reduce speed further on bends and where water pools.
Braking and grip. Wet surfaces reduce grip; brake earlier, progressively and in a straight line, and avoid sudden steering inputs on painted lines or metal covers, which are slippery when wet.
Visibility. Keep the headlight clean and correctly aimed. Wear high-visibility clothing. Do not use main beam when another vehicle is ahead or approaching.
The colleague. Decline the close-following escort. A vehicle following closely with hazard lights on can dazzle you in mirrors, compress your following distance and encourage you to ride faster than conditions allow. Agree instead that the colleague travels separately, or ride alone at your own pace.
Fatigue. If tiredness persists after repairs, the safest decision is not to ride at all. Stopping for a rest or postponing the journey is always preferable to pushing on through the dark section while fatigued.