Monday 14 January 2013

Drysdale V8 - Homebrew Aussie Eight

Image Source

When it comes to motorcycle production, Australia is not usually the first country that comes to mind. Even neighbouring New Zealand, with legends like Burt Munro and John Britten, has a reputation for clever motorcycle engineering – but rarely do people think of unique bikes when they picture the Aussie landscape.

Shame, that – because one of the most fascinating motorcycles in the world was made in Australia. Enter the Drysdale V8, the pet project and hand-built marvel produced down under by an enthusiastic engineer/mechanic by the name of Ian Drysdale.

In the 1990s there appeared to be a strange trend towards exotic and expensive boutique motorcycles. Tiny manufacturers, some borderline frauds, were popping out of the woodwork to take advantage of a perceived market for extremely expensive and hand-finished bikes for wealthy enthusiasts. Morbidelli was perhaps the best known, having shown their legendarily ugly and expensive 850cc V8 in prototype form from 1994-1998. There was also the stillborn (and horribly optimistic) 1500cc Norton Nemesis V8 project in 1998. Both of which will be the subject of future features here on Odd-Bike, have no fear.

Then there was Ian, toiling away on the other side of the world, who quietly unleashed one of the most interesting V8 projects of them all – The Drysdale V8, a rip-snorting eight cylinder Superbike. Not only that, but unlike the overly ambitious projects of the 90s, he succeeded in actually producing them in (small) numbers.
Ian sounds like the sort of engineer you’d like to have a beer with. A grounded, mechanically minded fellow who has a string of strange homebrew projects under his belt. A man who built his own minibike when he was a kid. A man whose previous motorcycle project was building a two-wheel-drive, two-wheel-steering dirt bike (dubbed the Dryvtech 2x2x2).
Where most engineers are terribly boring and generally butt heads with mechanics (“but in theory” or “but on paper” are two things that you must never say to a mechanic, lest you want to receive a Westcott upside the head) Ian is the kind of engineer/designer a mechanic can get along with. He is a clever man with big ideas that he actually applies in the real world, with an eye towards practicality and smart design that actually works. I picture Ian as the heroic backyard tinkerer, the man you wish was your dad, building weird and wonderful machines that push the envelope by virtue of being unhindered by considerations of mass production or profitability.

The V8 was developed in the mid 90s as a project to build a high performance 750cc superbike. In essence, it is a pair of Yamaha FZR400 top-ends mated to a common crankcase with a 90 degree V betwixt them. In execution it is much more than the sum of its parts, and the design brief is quite down-to-earth considering how exotic the final product is.

Image Source

In terms of making an exotic motorcycle, building a V8 is certainly a no-brainer by virtue of being virtually unheard of in the motorcycle world. But in terms of a racing motorcycle what advantage could a complex V8 have over a highly tuned four cylinder or a V-twin? The Drysdale was not the first - Moto Guzzi had campaigned a legendary 500cc V8 grand-prix machine from 1955-1957, and Ian admits that the Guzzi was a source of inspiration for his project.
Image Source

The short answer is lower piston speed and higher revs. Having a series of small cylinders with short strokes reduces the velocity of the pistons overall, allowing you to push the rev limit higher. Higher rev limit means more power - as long as you have good breathing and proper tuning, you can treat an engine like a air pump. More air in and out, more power. So more cylinders, more revs, more air, more power. That is really over simplifying things, but it gives you a basic idea of why you might consider building a superbike with twice as many cylinders as the competitions - assuming there were no displacement penalties. The Honda NR oval-piston projects came about due to a loophole in the rules for engine configuration - GP rules at the time allowed no more than four combustion chambers. So Honda made paired pistons that had an elongated combustion chamber with twice as many valves. So you had a "four" that was really a V-8 with the pistons mated together in pairs, each cylinder having 8 valves and each piston having two con-rods. Benefits and breathing of a V8, but technically (and legally) a V-4.

How high did the Drysdale V8 rev? 17000 rpm. "Race" limit was claimed to be a searing 19000 rpm. To put that into perspective the 2006 Yamaha YZF-R6 was claimed to hit 17500 rpm off the showroom floor, making it one of the highest revving production motors of all time - when in fact the actual limit was 16200, a little lie that got Yamaha into some serious hot water. The only production motors to come close to those sorts of rev limits are tiny 250cc four cylinders like the Honda CBR250RR. Despite this, the V8 had a relatively low piston speed - at 17000 rpm piston speed would be 21.5 m/s. That R6? At 16200 it would have been slinging pistons at 23 m/s (with a 42.5mm stroke).
Image Source

According to the Drysdale website, the V8 began as a project for a sidecar rig motor. From the official site:

The 750-V8 started out as an engine-only project when Ian was approached by two people (unbeknown to each other) in the space of 2 weeks to design a motor for sidecar roadracing. If a 17,000 rpm V8 isn't frightening enough - the initial design Ian proposed was a 1100cc vee twin 2 stroke with a projected 120 kW from an engine weighing just 40 kg - but the thought of such an engine fitted to a road going motorcycle was too frightening to contemplate. It became obvious that a four stroke was more desirable if development costs were to be recovered by selling the engine for road bike use as well.
As work progressed on the engine it became obvious that it was necessary to design the complete motorcycle concurrently as everything was going to be a tight squeeze with twice as many of most parts to fit into the same space. The compact, jewel like engine that emerged guaranteed that production of a complete motorcycle must be the first priority.

The result was a 749cc V8 with 32 valves, quad overhead cams, and a 56x38mm bore/stroke. The crankshaft is a flat-plane item with 180 degree crankpins, ala Ferrari V8. So imagine the sound of the Ferrari 355/360/430/458, multiply the rpms by two, and you have a good idea of what the Drysdale sounds like. 
Image Source

What made the V8 impressive was its use of off-the-shelf parts. The crankshaft and crankcase are custom items, as is the steel trellis frame and bodywork (and of course those stunning 8 into 2 headers), but aside from that just about everything in and the around the motor is made from readily available components. Aside from the FZR heads, cams, valves and pistons, you have a Honda oil pump, a Kawasaki alternator, Yamaha clutch and transmission, and a mix of Yamaha and Kawasaki suspension and chassis components.  This is where Ian's practicality shines through. He wanted to build an exotic that could be fixed, anywhere in the world, with parts from your local Japanese bike dealer.
Image courtesy Ian Drysdale

Not only that, the bike was designed for easy maintenance and repair. Clearly the work of a man who actually fixes motorcycles, rather than one who simply designs them. Reading the "design philosophy" for the project, you immediately realize how down-to-earth the whole endeavour really is:

1. To build a road legal factory racer- the highest performance motorcycle that could still be ridden to the corner shop for a loaf of bread.
2. To build a unique machine but still with worldwide parts availability - this has been achieved by utilising wearing parts from existing motorcycles where it didn't compromise rule #1.
3. To allow ease of maintenance either at home or at the track. Both the heads, the clutch, the gearbox, the alternator and the waterpump can all be removed with the engine still in the frame - the last four don't even require the removal of any bodywork.

Power was a claimed 160hp, which made it competitive with racing 750s of the late 90s. On the initial prototypes fueling was courtesy of eight CV carburettors, replaced by a slab of eight Keihin flatslides - which made for some finicky tuning and a really heavy throttle pull. Later he developed a custom Motec fuel injection system. Initial versions featured an underseat radiator, later moved to a conventional front position. Bodywork was a swoopy one piece design, available in "Any color you like as long as it is orange" with endurance-racer bug eye headlamps ala Honda RC30/45.

Period tests, what few there were, praised the V8 for its sparkling power, smooth engine and tidy handling.

Image Source

But the Superbike was not a one off. Ian had a few other ideas, and set about building a (very limited) production run of street oriented V8s for discerning clients willing to plunk down 70 000 AU$ plus for a hand-built Aussie motorcycle. First was the Superbike. Next came the Naked concept in 2002 - the Bruiser, best described as V8 powered take on the Ducati Monster, complete with a classic steel trellis frame.
Image Source

The Bruiser was to use an upsized version of the original V8, displacing 1000cc. The top ends now came from the YZF600, and the bore and stroke was increased over the 750. Like the Superbike, it made use of off-the-shelf chassis components (which were customisable by the client, as each bike would be hand built to order) married to a custom trellis frame design. It was still clearly a sporting bike, but far more relaxed than the Superbike with a classic muscle-bike stance, flat bars, and provisions for a passenger.

Image Source

Another interesting project was brewing in 2001. As MotoGP planned a switch from 500cc two-strokes to 990cc four strokes, Drysdale was prepping a 988cc V8 with the intention of offering a complete motor to teams looking for a turnkey option. The ultimate goal was to produce 240hp at 22 000rpm from a very lightweight and compact eight with an 80 degree V. Mockups were shown, spec sheets were published, and calls for investors were made. Sketches for a complete, rather pretty, Drysdale GP bike were also fielded. Unfortunately the project never materialized, but the launch website remains.

Image Source

In recent years Ian has kept a low profile. The company website hasn't been updated since 1999, and the GP site has been dormant since 2001. A 2003 update on the site showcases an interesting Royal-Enfield based V-Twin project. Most people had assumed Drysdale motorcycles were no more, and that the project had quietly disappeared.

Quite the opposite. Ian is still building V8s today. All you need to do is ask him. In fact, Ian was kind enough to send me some exclusive photos from his "assembly line".

Image courtesy Ian Drysdale

As I was unable to find much information regarding the current status of the project, or even any recent photos, I decided to reach out to Ian directly and see if he was still at it. Sure enough, he answered and informed me that yes, he was still working on them - in fact, he is currently working on what he says is the final customer order. So far four bikes and one spare engine have been built. After this one he hopes to build two final bikes - one for himself and one for his business partner.

Image courtesy Ian Drysdale

"Current pricing" has risen to around 100 000 AU$, with up-to-date components and revised fuel injection, and Ian laments that even at that price he isn't making any money on the project. It remains a labour of love.

I was curious as to what kind of feedback he had gotten from owners:

Well there's not too many of them, so I've got to know them all
personally ! They love their bikes of course, they can be pretty
sure that they're got the only one in their street.

My customers tend to be "tech heads" rather than rock stars or millionaires - they bought one as they appreciate the
engineering that goes into it, rather than for pure bragging rights.

As for what he is up to now:

The V8's are very much a side-line for my business, I do R&D work
for Chinese motorcycle companies - mainly ATV's and such like,
although I have done a couple of 2 wheeler engines ( neither of
which have gone into production ).

I also work closely with "Stealth Electric Bikes", a high performance
electric mountain bike manufacturer. I do a lot of their prototyping
work and even their tooling.

I asked Ian what he had planned for the future. As I hoped, he gave me an interesting answer. I won't give away too much but he is working on an updated 2 wheel drive system for dirt bikes, and a homebuilt helicopter project. As for that V8 Moto GP engine - "I touted that when the GP's were going 4 stroke - hoping to become a motor supplier to smaller teams, but I could never get the money to build a running prototype."
The Drysdale V8 was the product of a fertile mechanical mind with an eye for building an everyday exotic - a rare, high spec, bespoke machine that could be ridden regularly and fixed by any competent mechanic with off the shelf parts. The V8 is just one example of the quirky ingenuity of Ian Drysdale, a man who has built many odd and impressive projects over the years. After building a very limited number of V8 for discerning clients for the past 16 years, Ian is winding down production. It is the end of a truly spectacular and fascinating machine - and I hope that Ian gets the chance to build his personal bike and ride the hell out of it.

Interesting Links
The web home of the various Drysdale projects
An early ride preview of the V8 Superbike
Preview of the Cruiser/Bruiser 1000-V8
Video feature on the 750 Superbike

1 comment:

  1. Richard James22/11/2014, 16:11

    Having worked with Ian for a period of about five years (2004-09) as his CAD guy on some of the Chinese based projects I know that bench very, very well!