Lions Den Motorcycles Dirt Racer
By Ross Sharp - 26 Jun 17
There are numerous reasons people have set themselves up as custom bike builders, hopefully by now those still contemplating it will be aware that huge profits and a lavish lifestyle aren't synonymous with creating unique machines. If late, solitary nights in the workshop surrounded by 17 versions of a simple bracket and empty cans of Red Bull sounds like there perfect pastime - fill your boots.
Dan Thomas from Lions Den Motorcycles is one of those grafting creative types who derives more satisfaction from challenging himself rather than filling the bank account, which is evident from this build which was finished just in time for Bike Shed London 2017 last month.
Originally intended as a city hack Dan bought an untidy Yamaha XT600 with no intention of doing anything to it. But as is often the case, what if I just tweaked that bit, and sorted the..... crept in and before he knew it the Yam was splayed naked on the workbench. The slender off-road underpinnings and relatively pokey motor seemed to lend themselves to a café racer style build - the Dirt Racer was born.
Dan doesn't work to a render or bunch of sketches, preferring to fabricate by eye and instinct saying "I've been working on this bike on and off for the last two years, in between customer projects. I wanted to produce a prototype of the kind of machines I would love to build every day of the year. As with all my builds, I never know what the 100% finished article will be until I start. I don’t work from beautiful renders, just impulsive inspiration in my head. For me the excitement comes from getting stuck in and seeing new ideas appear in front of my eyes."
The frame received a hearty going-over with an angle grinder, chopping off ugly bits and smoothing the rest. The new subframe is tightly triangulated to leave the wooden tail pride of place, more on that later. A stock of Fireblade parts provided the front and rear ends, a starting point at least - the rear shock was swapped-out for a one-off Hagon unit, now pivoting on a modified and braced swingarm. The rear hub is stock XT but the front is from a Triumph Tiger, both relaced by Essex Wheels and Engineering to incorporate wider rims and modern Avon AV66 tyres.
Seeing as James the wheel builder also has the equipment for proper engine work the XT was rebored, rehoned and the head gas-flowed to work with the new Wiseco piston and brace of Keihin CR carbs. Yes it's a single but the Yam runs a twin port head. Dan is keen to explore internal performance upgrades on future builds, a element often missed in the predominantly aesthetically focussed custom scene. The free-flow stainless zorst is Dan's own handiwork, made from precision mandrel bends and neat TiG joints, rather than the weldist-willy-waving lobster-back method that has come to the fore of late.
The XT motor runs a dry sump lube system requiring some form of oil tank. Harley builders have been wrangling the conundrum of hiding or embellishing the humble tank since forever but the new wave scene has predominantly centred around wet sumped donors. Dan's solution sure confused punters during the Dirt Racer's unveiling at the Bike Shed show. What looks like an additional exhaust is a snake of stainless tubing carrying just the right amount of 10W40, sealed with a skilfully turned brass cap. In fact there's a host of neat finishing touches on this bike that jump out the longer your stare lingers. Dan likes nothing more than spending hour after hour turning and knurling on the lathe.
A single headlight mounted in an intricately welded bracket would have looked great up front - but that not's Dan's style, he decided to make his own. The outer rim is aluminium, rolled on the English Wheel but the centre plexiglass-glass cover took slightly more trial and error. First-off there was an attempt to warm the acrylic in a kiln, but after a few fires this idea was superseded by a 4 heat gun and 2 blow torch, MDF mould in a custom MDF cabinet method - of course! Behind sits a pair of projection headlights.
The most striking element of the Dirt Racer is the seat. Dan considered ally and fibreglass options but a visit to a neighbours woodworking workshop unearthed a chunk of Zebrano (Zebrawood as it's sometimes known) along with the inspiration to produce something a bit special. 10 foam moulds later and Dan was ready to commit to wood, MDF though, once happy with the final shape he broke out the striped, layered hardwood and began shaping. Once happy the epoxy sealer could be applied he had to be patient "I poured once a day for 9 days to build up the layers as my inspiration was the million pound speed boats you see darting across Lake Como. It was a process that tested my patience as many times, just after a pour, a fly would buzz right into it and set itself into the finish like the bug in the amber on Richard Attenborough’s walking stick in Jurassic Park."
A series of threaded inserts and bearings allow the seat unit to pivot, raised and lowered by a single gas strut. A completely unnecessary display of over engineering but once you've had a feel of the smoothness and satisfying clink of the magnetic closure you wonder why all café racers aren't like this. Ever the perfectionist Dan wasn't 100% happy with the tone of the leather saddle and mid-show sourced a dye to darken the hide slightly.
Front and rear mudguards are beaten and wheeled, probably a couple of day's work on their own. Whilst at it the scalloped sides were made for the Suzuki GN fuel tank and grafted in. Appliers of fine finishes Black Shuck Kustom were entrusted with the paint job. A light dusting of gold pearl brings the black gloss to life, contrasting with the crackle finish on the barrel, head and crankcase. The outer cases are covered with high-temp black, also with a hint of gold in the base layer - fancy. Local powdercoaters Amwell Blast Coat took care of the frame, swingarm and yokes, embellished with more brass.
And as you may have guessed by now the switchgear isn't from a catalogue either but a Lions Den design brought to life by master machinists Demeanour Customs. Powering the whole lot required a wiring harness of a standard to match the rest of Dan's efforts saying "I am not very good at wiring nor do I wish to improve, this is where Richard Prowse of Motorcycle Wiring Specialists was called incomes in. He's methodical, meticulous and down right marvellous. What he's achieved is astonishing. A totally bespoke loom that has to hide some very tricky components including the Motogadget components, all wrapped-up in a super neat braided configuration, which almost disappears into the bike. Other tricks he uses include hand tied knots rather then cable ties and different braids depending on where the loom is positioned on the bike, for example a high temp braid where the loom sits next to the cylinder head".
Seeing the size of the bags under Dan's eyes when he rolled into Tobaccos Dock on Bike Shed London 2017 setup day you could we just knew he'd put every last ounce of himself into this build. Being a one-man-band isn't easy but Lions Den are raising their own bar with every project and look to have a bright future. Dan might not be much closer to piloting his own Riva across lake Como but for now he seems to be living the dream.
More from Dan and Lions Den Motorcycles on Bike Shed Archive | Instagram | Web | Facebook
Images by Autohouse London
And check out Dan's vid here