The ol’ bamboo
Tri-sept Cycles’ Mike Cubbage explains how a chance encounter led to creating a monocoque bamboo bike
Mike Cubbage was never particularly interested in cycling. He had a successful career as a designer behind him, working as an air-conditioning draughtsman before moving to General Motors, where he helped convert a four-door Chevrolet into a new threedoor hatchback. Then one day an old Y-framed Trek mountain bike parked at a local college caught his eye.
‘I saw it and thought, “I could do that.” So I went home and designed a frame that was two flat aluminium plates held apart by a ladder construction.
I then took it to show a mountain bike magazine in Bath and the guys quite liked it but the managing director asked, “What other materials can you make the frame from?” When I said I could do it in laminated wood he told me to ditch the aluminium and go down that route.’
To make his earliest prototypes Cubbage cut the frame and stays from a board of birch plywood with veneer on either side. ‘The first prototype was a very thin, simple bike and it would wobble a bit when people rode it. I took it to somebody who made frames, and he tried it out and suggested some changes and areas to thicken. So the next prototype looked like a normal bicycle and was good to ride.’
That still wasn’t satisfying Cubbage, though, so he started experimenting.
‘I went off-piste. I was thinking,
“It’s a new material, let’s do some new shapes, why not put some curves in?” That didn’t get a good reception, though. People were confused by both the shapes and the material so I stopped for a while as I was feeling like I wasn’t getting anywhere.’
With doubts over the frame design it was time to make a change.
‘I knew there were bamboo veneers that were 5mm thick, so I knew I could possibly make a 25mm thick board by cross-laminating the veneers and therefore make the same frame entirely from bamboo.’
It was a safer bet given the history of tubular bamboo bikes; he knew the material would perform well with a high strength-to-weight ratio and vibration dampening qualities and felt more comfortable with its sustainability – bamboo roots aren’t damaged in harvest and therefore don’t need replanting.
The new material led to another change in shape and, having previously drawn up designs for a track bike, Cubbage decided to make a road bike and set off to find a new supply chain.
‘I took the drawings on holiday to Cape Town, where I used to live, and found people who could supply the bamboo, as well as people with the daylight presses to glue it and guys who could do the metal work. They pulled
out all the stops and we took it to an exhibition in the city.’
That was how this, the first official Tri-sept Cycles bike, was born.
Plant based
With the sourcing, pressing, cutting and metalwork done in South Africa, the frame’s four pieces – half as many as tubular bamboo frames – are sanded down and put together by Cubbage at his kitchen table in Buckinghamshire, where he then finishes it off with a two-part epoxy glue and Danish oil.
To pick the right components he enlisted the help of his local bike shop owner in Marlow and they settled on Shimano 105 groupset, DT Swiss PR 1600 aluminium wheels and a Pro seatpost, as well as a Hope headset and a Bontrager carbon fibre fork. This bike weighs in at 12.45kg, though Cubbage claims it could be lower, explaining, ‘The frame is a combination of strand-woven bamboo and vertical bamboo. Strandwoven is 50% heavier and denser so a frame of purely vertical bamboo – which I do have – comes down to about 11kg.’
Before putting his product on sale, Cubbage wanted to prove the bike’s credentials. He didn’t expect people to put complete faith – and money – in a materially and aesthetically new construction like his. He sent it out on a few trial runs in 2019, mainly sportives in the UK and in South Africa but also a trip over Belgian cobbles, and the feedback confirmed his expectations.
‘Everyone reports the same: it rides beautifully. It’s smooth, quiet and the frame is completely true. The word that comes up the most is confidence. There are no creeks or groans from the frame and the guy who rode in on the Cape
Town Cycle Tour said that although he thought it was a bit heavy when he first picked it up, it actually climbed well, was fast on the flat and flew down hills.’
Trials done, Cubbage named his bike Tri-sept after the lucky numbers three and seven, and planned to launch his business in 2020. However luck was clearly not on his side as the Covid-19 pandemic put things on hold.
Refreshed for 2021, Cubbage is exhibiting at the Bespoked Handmade Bicycle Show in Harrogate in October, and hopes that his new business will grow just as quickly as the material his bikes are made from.
Cubbage sent it out on a few trial runs in 2019, mainly sportives in the UK and in South Africa but also a trip over Belgian cobbles