Racer Cave at Mulu: which headlamp when both hands are on the rope?

A muddy caver in a helmet climbing a wet rock slope in a cave with both hands on a knotted rope, lit only by the headlamp on the helmet.

Doing Racer Cave at Mulu? Both hands go on the rope, so the light goes on your head.

The Racer Cave trip is guided and graded intermediate. You climb up and down passageways on ropes, scramble over rocks and squeeze through gaps, with no lit path. Travellers spend about 3 hours underground.

Short answer

First, ask the park office what it hands out on the day. If you are bringing your own: the Nitecore HC65 UHE headlamp on its middle setting, waterproof to 2 m under water (IP68) and running on an 18650 battery you can swap, and a second light with its own battery in a sealed bag, the NU20 Classic.

See the kit ↓

The day at a glance

The park’s own booking page describes the Racer Cave adventure caving trip. It publishes no schedule and no duration, so the figures below come from the park’s brochure and from travellers.

You need a group of 3 to 6 people and an advance booking. Park Management assesses whether you are suitable. We cannot confirm availability for any date.

  • About 3 hunderground, in three travellers’ accounts
  • 1 km inand 1 km back out, from one traveller’s account
  • 15 ft, 30 fta rope climb up and a rope descent, from one traveller’s account
  • 3 to 6people per trip, minimum age 12, from the park page

What light the park gives you

  • The park’s Racer Cave page today says: “Bring your own headlight.”
  • The park’s adventure brochure, dated May 2020, says lights and helmets are provided and asks you to bring a spare torch.
  • Travellers from 2010 to 2025: three say they were given a helmet with a light, or a head torch. One account from 2017 lists your own torchlight as something to bring.

Ask the park office what it issues on the day. Neither document says the other is out of date.

The day in order

  1. Park officeYou meet your guide.
  2. Boat25 minutes by the brochure, 10 to 15 minutes in travellers’ accounts.
  3. The entranceHarness, helmet and lamp are fitted, and you get a safety briefing.
  4. Squeezes and mudSideways gaps and slippery ground.
  5. Rope climbsUp and down.
  6. Lights offThe guide’s moment of darkness.
  7. The returnBack out the way you came, then the boat.
A Ridley's cave racer snake coiled on a clay floor inside Racer Cave, lit by a hand held torch or flash.

The cave floor in Racer Cave, 16 April 2025. It shows a Ridley’s cave racer snake on clay and mud at hand height.

Photo: Calistemon, CC BY-SA 4.0, via Wikimedia Commons, resized.

Your day, step by step

The park publishes no times, so these rows follow the order of the day.

Park officeHeadlamp off
Check what you are handedIn one account the helmets with attached lights were picked here, before the boat. In another they were fitted at the cave entrance.
Boat to the entranceHeadlamp off
Daylight on the riverYou hold on and your bag sits on your lap.
Two people in a narrow longboat on a brown river through rainforest, helmets with headlamps resting on their knees and a small dry bag on a lap.
The entranceHeadlamp on
Switch on hereUse the middle brightness setting (100 lumens). Past this point the only light is your group’s lamps, and there is no lit path.
Two cavers and a guide at a cave entrance, one pressing the switch on the other's headlamp, daylight and ferns behind them and darkness ahead.
Squeezes and mudHeadlamp on
Rock a few inches from your faceYou turn sideways through gaps on wet, slippery mud. Stay on the middle setting.
A caver in a helmet turning sideways to squeeze through a narrow gap between wet limestone walls, lit by the headlamp on the helmet.
The rope climbsHeadlamp on
Both hands on the ropeYour hands are on the rope or the rock, and in places you slide on your seat. The light stays on your head.
A caver in a helmet and harness lowering themselves down a wet rock wall on a fixed rope with both hands, a second caver's lamp far below in the dark.
Lights offHeadlamp off
The guide has everyone switch offIt is pitch black. Hold either button of the HC65 for one second to switch off. To switch on again, hold the power button for one second, and it comes on at the middle setting.
Almost total darkness inside a cave with only the faintest outline of a rock wall and two helmeted heads.
Back to the boatHeadlamp on
The way outAccounts describe a final rope climb and squeeze on the way out. Switch off when you are back in daylight.
Lodge paths at nightLow light
Boardwalks and jungle pathsPaths link the park headquarters and the accommodation. The NU20 Classic is the light for these.
A person on a wooden boardwalk through dark rainforest at night, a small headlamp on a thin cord lighting the planks ahead.

How much runtime does your headlamp need?

About 4 hours 15 minutes for the cave. That covers 3 hours underground, 15 minutes of entrance checks and an hour spare for delays. These are our planning figures, not a park rule.

our 4h15 allowance
What you need
Underground, 3 h Entrance checks, 15 min Spare for delays, 1 h
HC65 UHE headlamp
HC65 UHE headlamp, middle setting (100 lumens)
HC65 UHE headlamp
HC65 UHE headlamp, high setting (400 lumens)

One battery gives about 31 hours on the middle setting and 14 hours on the high setting, measured at 26°C. The light gets dimmer as the battery drains. Either covers the cave at least three times over, so this kit has no spare battery. Turbo (2,000 lumens) runs for 2 hours and steps down, so it is not a setting to walk a cave on.

The lodge paths are separate. We allow 90 minutes over two evenings, 30 minutes of walking and 15 minutes of close tasks each evening. The NU20 Classic gives about 5 hours on its high setting.

How far ahead you need to see

A caver's headlamp-lit view up a muddy rock slope with a knotted rope, two gloved hands on the rope and a guide's small lamp far ahead. 0.5 to 1 m: the next foothold and the rope Up to 3 m: handholds and uneven ground Arm’s length: close walls and gaps

Illustration, not a measured beam pattern. The distances are our own, not measured in Racer Cave.

What those distances look like

  • 0.5 to 1 m: about an arm’s length
  • 3 m: about one storey of an HDB block

The 48 m range on the middle setting is where the beam fades to moonlight level. You see rock clearly for a fraction of that, and on a rope the near part of the beam is what matters.

If the battery runs down, or the lamp fails

Battery runs down

Charge the HC65 before the trip. The battery is one 18650 cell, and you swap it by unscrewing the battery cap.

Lamp fails, drops or gets lost

A second light with its own battery, such as the NU20 Classic in a sealed bag. A spare battery cannot fix a lamp that is broken or gone.

Practical checklist

  • Charge the HC65 before the trip. It takes about 2 hours over USB-C.
  • Use lockout, so the lamp cannot switch on in your bag. With the lamp off, hold both buttons for 2 seconds until the small white light flashes 3 times. Do the same to unlock it.
  • Check the headband fits over the helmet you are given. We have not tried it over a caving helmet.
  • Practise switching off and on in the dark at home, until you find the right button by feel.
  • If you carry another 18650 cell, it must be a button top cell that can deliver more than 8 A. A flat top cell does not work in the HC65.
  • Keep the NU20 Classic in a sealed bag, because it is not for submersion.

The kit we’d pack

HC65 UHE headlamp
Main headlamp
HC65 UHE headlamp
S$179
  • Middle setting: 100 lumens, about 31 hours on the included battery
  • Waterproof to 2 m under water (IP68)
  • 152 g with battery and headband, and the 18650 battery swaps
  • Two differently shaped buttons, so you can tell them apart by feel
View product →
NU20 Classic headlamp
Second light
NU20 Classic headlamp
S$49
  • Its own sealed battery, charged over USB-C in about 1h20
  • 200 lumens for about 5 hours on its high setting
  • Protected against rain and splashing (IP66)
  • 38 g with headband, and it covers the lodge paths at night
View product →
Headlamp and second light S$228

The NU20 Classic is your second light. A lamp the park issues you is a second light too.

Already own a headlamp? Check it against this list.

  • Waterproof to 2 m under water (IP68), or kept in a sealed bag.
  • Runs about 4 hours 15 minutes on a setting you can climb by.
  • A battery you can swap.
  • A strap that stays put over a helmet.
  • Buttons you can work by feel, with gloves on.
  • You have a second light with its own battery.

Other headlamps that also work

NWH20 headlamp
Helmet clips in the box
NWH20 headlamp
  • Four hard hat clips and a headband in the box. It is the only lamp here with helmet clips.
  • 300 lumens for 12 hours on its battery pack. Protected against rain and splashing (IP66).
S$119
View headlamp →
HC60 UHE headlamp
Lower cost, same idea
HC60 UHE headlamp
  • 140 g with its 18650 battery. Waterproof to 2 m under water (IP68).
  • 400 lumens for 14 hours on the middle setting.
S$139
View headlamp →
HA15 UHE headlamp
AA batteries
HA15 UHE headlamp
  • 65 g with an alkaline AA battery. Spare AAs are cheap and easy to find.
  • 100 lumens for 9 hours on one alkaline AA, or 4 hours at 200 lumens. Protected against rain and splashing (IP66).
S$69
View headlamp →

Runtimes measured at 26°C on the setting and battery listed.

What travellers describe

These are personal accounts, not endorsements of any product. None of these travellers is known to have used Nitecore gear. Blog dates are publish dates, not trip dates, and are not current park policy.

Questions

Does the park give me a headlamp?

The park’s page and its brochure disagree, and we have not asked the park. The three sources are listed under “What light the park gives you” in the day at a glance. Ask the park office what it issues on the day.

Should I still bring my own headlamp?

If the park issues you a working headlamp, it can do the job. Both park documents ask you to bring a light: the page says your own headlight and the brochure says a spare torch. A headlamp keeps both hands free for the rope.

Will it get wet?

The HC65 is waterproof to 2 m under water (IP68). The NU20 Classic is protected against rain and splashing (IP66), not for submersion, so keep it in a sealed bag. No account of Racer Cave describes wading or swimming. Travellers describe mud, slippery ground and, in one account, water falling in the cave. The water rating does not cover a day of mud or knocks against rock.

Can I use my phone torch?

Both hands go on the rope and the rock, and a phone torch needs one of them. A headlamp keeps them free.

How long does one charge last?

One battery gives about 31 hours on the middle setting, and the cave needs about 4 hours 15 minutes of light. See the runtime section.

Does the headlamp fit over a helmet?

We have not tried the HC65’s headband over a caving helmet, so check it fits the helmet you are given. The NWH20 has four hard hat clips in the box, and it is listed under other headlamps.

I am also doing Kinabalu, which headlamp?

See our Kinabalu headlamp guide. That climb is longer and colder, and we recommend the HA29 UHE there.

Questions about your own gear? Contact the team.

Sources and credits

  1. Gunung Mulu National Park, Racer Cave page, read 6 October 2026. mulupark.com
  2. Gunung Mulu National Park, adventure brochure, footer dated May 2020. mulupark.com
  3. Mog and Dog Travels, Visiting Mulu National Park. moganddogtravels.com
  4. OMP VS. the World, 15 May 2011. ompvstheworld.wordpress.com
  5. Freakout, Racer Cave, 20 August 2017. chillout-soulout-freakout.blogspot.com
  6. Eric’s Travel Blog, December 2013. ericstravel.blogspot.com
  7. ASEAN tourism article, 10 May 2010. visitsoutheastasia.travel
  8. Nitecore, HC65 UHE manual. nitecore.com
  9. Nitecore, HC60 UHE manual. nitecore.com
  10. Nitecore, NU20 Classic manual. nitecore.com
  11. Nitecore, HA15 UHE manual. nitecore.com
  12. Nitecore Singapore, HC65 UHE product page. nitecore.sg
  13. Nitecore Singapore, NU20 Classic product page. nitecore.sg
  14. Nitecore Singapore, NWH20 product page. nitecore.sg
  15. Nitecore Singapore, HC60 UHE product page. nitecore.sg
  16. Nitecore Singapore, HA15 UHE product page. nitecore.sg
  17. Wikimedia Commons, Ridley’s Cave Racer snake in Racer Cave, April 2025, Calistemon, CC BY-SA 4.0. commons.wikimedia.org
  18. Nitecore Singapore, Kinabalu headlamp guide, for readers doing both trips. nitecore.sg

This is a buying guide for headlamps, not caving or safety advice. In the cave, follow your guide, your tour operator and Gunung Mulu National Park on route, equipment, timing and safety.

We have not tested these headlamps in Racer Cave. Scene illustrations on this page were created for this guide and do not show a specific trip.

Last reviewed 6 October 2026.