As he exits the front door of the Buddy Lodge Hotel in a rush, the guy with the Khmer-check scarf almost takes me out.
We're pedalling along Khaosan Road, the centre of Bangkok's backpacker district, and it takes a quick nudge on the handlebars to miss him.
Bangkok is never dull, but two wheels at night adds more than the usual spice to the equation.
I'm doing the Bangkok Night Ride with bike-tour specialist Grasshopper Adventures: four hours, 13 kilometres and the promise of a very different side of the city.
We start out at Grasshopper headquarters, in Ratchadamnoen Road near the Democracy Monument. After a quick briefing - lights on, use your bell - and a weaving test ride on our fat-tyred Merida mountain bikes we leave the broad, clogged artery in favour of the narrow capillaries heading for the Chao Phraya River.
Our zigzag journey takes us first through the back lanes of the Khaosan Road district. Almost every ground-level shopfront is a bar or restaurant, and people are already sitting down to eat or lounging on cushions.
The smells are delicious, a mix of spicy aromas as we pass from one steaming wok to the next.
Massages are another major industry here, with girls touting for business in sing-song voices. In one parlour four men are having their feet massaged, each one deeply engaged with his phone.
After winding around the walls of Wat Chana Songkhram, where monks are chanting their evening prayers, we hit the north-west corner of the royal palace and walk our bikes through the waterfront market.
There are still a few long-tail boats howling along the river, but we're waiting for a commuter ferry that will take us and our bikes to Thonburi.
Once across we plunge into more alleys, darker this time. A couple of times we have to cut across major roads. Our guide huddles us together, waits for a break in the traffic and shepherds us over.
This is another Bangkok. Thonburi is the older and more traditional side of the river, the capital for a short period in the 18th century, and a quieter part of the city.
After a ride of about 20 minutes from the ferry we turn into the gates of Wat Arun, the Temple of Dawn, one of the landmarks of the Thai capital.
During the day the temple is thronged with tourists, but the only people there tonight are four young monks and a photographer. At night the temple is startling. Its ceramic tiles sparkle in the spotlights as the towering, Khmer-style prang (steeple) tapers into the night sky.
Our guide is Tammy, a Thai who weaves acrobatically through bollards and makes daredevil leaps off the kerbs.
She escorts bike tours all over Thailand, but tells me Thai women don't like to work as tour leaders for cycle groups because the exposure darkens their skin. ''I don't care,'' she says. ''I just like to ride. Want to see some fish?'' She puts some coins into a vending machine and the bowl below fills with pellets.
She then walks to the riverside and tosses in a handful and the water boils with whiskery catfish. Most are hand-length, but there are several giants in the whirling silver ball. ''Can you catch them to eat?'' asks Yurika from Bali, with a sensible Asian eye on such matters. ''No, not by the temple,'' Tammy says, ''But if you go just a little further away, no problem.''
It's starting to rain when we swing our legs back over the saddle and set off through narrow passageways strewn with hazards for the unwary rider. We're pedalling through a neighbourhood of close houses, past front doors where people are snoozing in front of TV sets, dodging the feet of men drinking coffee together on their front step, avoiding stray cats and parked scooters, and trying not to run over the shoes that everyone leaves at their front door.
It's dark now, lit only by the stabbing beams of our headlights.
After a while we hit the riverbank and ride along a footpath suspended above the water. Some of the houses along the river are old-style teak with shutters and steps that lead to the water.
This side of the river is lower, Tammy tells us, and during the floods of late 2011 everything went under.
At the Memorial Bridge we take the footpath across the river, heading for the market that erupts in a blaze of colour on the far side. Stallholders are threading marigolds onto garlands and arranging lotus flowers and roses, which will be used for temple ceremonies and weddings.
This is Pak Khlong Talat, Bangkok's biggest flower market - stall after stall crowded with blossoms and the perfume of jasmine. When we get to the vegetable market, Tammy buys some spicy pork kebabs. They're delicious. On the way back to our bikes we buy sticky rice with banana, parcelled in banana leaf and sweetened with grated palm sugar. A bite of happiness for less than 20¢.
Next stop is Wat Pho, home to the reclining Buddha that is one of the city's biggest draws, but we are the only ones there. Tammy says they closed the complex when US President Barack Obama visited in November last year, ''and now you get to see it like Obama, all just for you''.
We're back on the bikes for a final return ride to the Grasshopper shop. It's raining steadily as we pass through one of the city's nightlife districts and there are a few women in rather less clothing than might be expected on a cool and damp night.
Yurika tells me they remind her of the women who sell spicy green papaya salads in the Hua Lamphong district ,''but they are not selling spicy papaya salad''.
Back at the Grasshopper headquarters, it's high fives all round and we're done. Happily for me, we're close to Methavalai Sorndaeng, one of my favourite Bangkok restaurants , and maybe I just might squeeze in a massage before midnight.
The writer was a guest of Qantas and The Metropolitan by Como.
The Metropolitan by Como is a calming and stylish hotel in a central location with an outstanding reputation for its food. City Rooms start from 3600 baht ($146), but the Metropolitan Rooms, starting from 4400 baht, are huge and well worth the money. This is also the home of Nahm, David Thompson's acclaimed Thai restaurant, voted one of the world's top 50. Book well in advance. comohotels.com.
The Bangkok Night Ride with Grasshopper Adventures costs US$32 ($40.6). grasshopperadventures.com.
- Sydney Morning Herald