There’s an extended historical past of purpose-built vehicles that use motorbike engines. Mix a robust sufficient motor with a lightweight sufficient chassis, and the outcomes may be very passable. However what about sticking a automotive engine in a motorcycle? That’s a wholly completely different ballgame.
Followers of classic German engineering ought to acknowledge the ability plant on the coronary heart of this hand-built chopper. It’s powered by the air-cooled four-cylinder boxer from a VW Beetle—and, as you’d think about, it took a bit little bit of ingenuity to place collectively.
It’s the work of Paul Clark—an English hobbyist that builds {custom} bikes for the love of it, slightly than for industrial acquire. A fan of older and rarer marques, he’s constructed up fairly a set of machines (and spare elements) through the years.
“I’ve constructed a Dnepr chop, and a J.A.P. rotavator-engined bike, in addition to others,” he tells us. “These bikes are usually not shiny—removed from it—and they don’t seem to be one thing the place somebody will pull alongside and say ‘I’ve received a kind of.’ They’re distinctive to me, my type, and I really like them—nevertheless it’s additionally good when different individuals admire them too.”
Paul additionally likes to maintain his initiatives low-cost, by utilizing as many up-cycled and scratch-built elements as attainable. This one kicked off with an eBay discover; a £300 [about $379] VW Beetle engine begging for a house. “Utilizing the engine as a base, sat on my workshop ground, I began to visualise the completed bike in my head,” he says.
The primary problem was to connect a transmission to the motor. Paul mated a Dnepr MT 650 gearbox to the VW mill, through concentric flanges that had been waterjet-cut from aluminum. A Dnepr clutch and flywheel had been tailored to work, too, together with the alternator from a Kubota mini digger.
Wassel Evolution carbs inhale via an Amal velocity stack, hooked up through a {custom} manifold. The snaking pipes on both aspect of the engine appear messy at a look, however when you hint them fastidiously you’ll have the ability to make out the road of Paul’s bespoke chrome steel, four-into-two exhaust system.
“As soon as they had been fitted, they had been dangerously near the rider’s legs,” he provides. “I didn’t need exhaust wrap or warmth shields, so I opted to purchase some knee excessive boots to put on when driving; the issues we do to maintain the aesthetics as we wish them!”
With the fundamentals out of the way in which, Paul arrange a makeshift wheel alignment jig utilizing a metal beam. 16” rims had been laced to a Dnepr entrance hub and a Honda Goldwing rear hub, shod with contemporary rubber, and set within the jig, together with the engine and gearbox.
Beginning with a partial 1983 Honda Goldwing body, Paul mocked up the chassis with bits of spare tubing and broom handles (sure, broom handles). The ultimate body was welded up out of metal tubing, once more procured from eBay, with the triples and forks from a Yamaha XJR1300 up entrance. The body’s 50 mm chrome steel prime tube additionally acts as an air reservoir, for a TC Bros ‘Air Journey’ system that sits beneath the slim chopper seat.
“I feel that the seat at all times seems to be higher as near the tire as attainable,” says Paul, “particularly as there is no such thing as a rear mudguard. It occurred to me early on that it could be nice to have a seat that goes up and down—however I didn’t need springs, so I opted for an air bag. It seems to be nice when the bike is parked up, and is admittedly snug when driving.”
A small 12 V air compressor ‘fees’ the highest body rail to round 40 PSI, which is sufficient for the seat to go up and down about 4 instances. Look carefully, and also you’ll spot a small air stress gauge mounted simply in entrance of the seat.
If the gas tank seems to be acquainted, it’s as a result of it got here off a Triumph Bonneville. Paul cut-and-shut it to take a seat wider, and tailored it to suit his body. Simply in entrance of it are custom-made handlebars, with Massive Port Beston-style grips, a throttle, the brake and clutch levers, and little else.
Paul doesn’t like new and glossy bikes, so the body was shot blasted and zinc plated, then wiped over with a firearm coating and range polish. That gave it an aged forged look that may match the engine. First Alternative Physique Store dealt with the crimson paint job, Central Wheel Elements did Paul’s powder-coating, and Brimscombe Platers tackled all of the sprucing and plating jobs.
As a last contact, Whiteway Craft Foundry constructed a small battery field that doubles up as an alternator mount. The truth that it seems to be a bit like an previous VW bus is not any accident.
With the challenge nearing the end line, Paul contemplated if his 132-pound body would have the ability to kickstart (sure, he opted for a kickstarter) the chunky VW boxer. “Sure, it began—what a reduction” he quips. “It’s really fairly straightforward to kick over.”
Virtually prepared for his first shakedown run, Paul then hit the most important snag of the challenge. “I’m a little bit of a hermit when constructing,” he explains, “however recommendation about unusual technical particulars is at all times available from my oldest buddy, Neil Baxter. He came to visit for a cup of tea one night and casually mentioned, ‘are you positive the rear wheel isn’t going to run backwards with the shaft on that aspect of the wheel?’”
“The propshaft was carefully becoming with no room to vary something. We tried it, and, shock and horror, the wheel was working backwards! I used to be so dejected at this that I practically scrapped the entire challenge—however with some encouraging phrases, it was a case of checking out this unexpected drawback.”
In the long run, Paul needed to scrap the Goldwing rear wheel and bevel field, and change them with a repurposed Dnepr last drive and hub. With a {custom} metal cowl on the ultimate drive, the entire association solely simply match into the body—however the necessary factor is that it did match. Two weeks later, the VW bike was prepared for its shakedown.
“I received 20 ft, and it died,” says Paul. “A burnt-out coil gave the impression to be the issue. Two additional coils later, it turned out that that the Lithium battery wouldn’t behave with the alternator, and changing it with a small gel battery sorted the issue.”
Lastly on the highway, Paul’s pleased to report that the bike pulls robust, topping out at round 60 mph. However because the Dnepr transmission has a 4 gears and one reverse gear, he may modify it so as to add a fifth gear.
“It’s not humorous if you’ve spent a variety of hours constructing a motorcycle, solely to seek out that it has one ahead gear and 4 reverse gears. Having to chop up a freshly constructed, laced and painted wheel is annoying within the excessive. That specific drawback practically did it for me—however I’m so glad it received sorted and the bike received completed.”
“The bike has its personal brand, which is a reverse VW; the W on prime with the V beneath, as a reminder to examine such issues a lot earlier within the construct subsequent time. It additionally goes by the title of ‘Bootsy,’ a reminder to place my new very excessive boots on except I need to set hearth to my trousers.”
Photos by, and with because of, Del Hickey
