One of the two grandaddies of modern folding bikes, DAHON (the other being, obviously, the UK’s Brompton Bicycle), finally has its first true Brompton-style tri-fold bike. Called the DAHON LUNDEN D7, the frame integrates the American bicycle maker’s DELTECH (short for Dahon Lateral Enhanced Technology) and Super Down Tube that enhance structural stiffness, optimize power transfer, and improve overall ride stability and acceleration.
Another key difference is that it has an adjustable-height handlebar—something Brompton tri-folds and their clones do not have. It shares a similar folding and unfolding process as Brompton-style tri-fold bikes, though it does require a few extra steps. You need to rotate/tilt the handle, and you may also need to adjust the height of the handlebar prior to executing the 3-step quick folding/unfolding made famous by Brompton.
Additionally, you will need to remove the quick-release pedal on the left and insert it into the pedal socket located at the rear of the frame. Of course, you can choose not to if you are laying the folded LUNDEN flat. But it will make carrying easier. Trust me. I speak from experience. If you love your shin/calf, you ought to remove the pedal.
While the LUNDEN has the look and feel of Brompton-style foldables, it benefits from DAHON’s years of experience in making folding bikes. The LUNDEN D7 uses a CR-MO (chromoly steel) frame. Supporting components include an aluminum handlebar paired with a DAHON Forged two-piece CR-MO handlepost, an aluminum seatpost topped with a DAHON Comfort Saddle, a heavy-duty aluminum rear rack, and plastic fenders. It is equipped with a 7-speed drivetrain and rolls on 16-inch lightweight aluminum wheels wrapped in KENDA 16” × 1-3/8” tires. It has a trigger shifter, in case you need to know.
Thanks to the generous use of aluminum, DAHON managed to keep the weight to a lightweight 26.9 lbs (12.2 kilograms). The DAHON LUNDEN D7 tri-fold bicycle was announced in March, and it is now available in the US in a choice of colors for US$1,399.
There’s also a 20-inch model, which is called LUNDEN 20” for now. While it shares the same model name as the LUNDEN D7, it looks nothing like the D7 as far as the frame design goes. Where the D7 is a city folding bike and has the iconic round tubular frame, its larger sibling is designed for adventure (read: gravel and rough roads) and rocks DAHON’s signature flatter frame.
The frame is completely redesigned for extreme rigidity, featuring a direct linkage between the headtube and the bottom bracket, a strengthened seatstay for extra stability, and speed. That’s right, this model features the proprietary DAHON-V Tech, which includes the patented DELTECH and an adjustable handlebar. Another star feature is the innovative Dynamic Suspension System that affords quick, on-the-fly damping adjustments based on road conditions.
The 20-inch model benefits from DAHON’s patented tri-fold frame, lightweight Dalloy aluminum, and a forged alloy radius telescope (adjustable, as previously noted). It is outfitted with a Shimano internal-gear 8-speed drivetrain, rolls on 20-inch wheels with 20” × 2.0” multi-terrain tires, and has TEKTRO hydraulic disc brakes for stopping duties.
A couple of worthy mentions include a multi-segment adjustable seatpost for precise micro-adjustments in height and angle, a quick-release pedal, soft-tail–hard-tail switching, and an integrated cargo rack with roller wheels. These are what we know about this yet-to-be-available tri-fold bike from DAHON. The LUNDEN 20” made its debut at CABDA Midwest on February 5–6, 2026.
Images: DAHON.
