Why would you customize your bike? It almost seems like a silly question, because there are so many valid answers to it. Maybe you hate the mirrors that came with the thing, or you want to carry luggage. Maybe you love it, but the ergos aren't quite right and so you want to change them. Or maybe it goes even further, and you just want to do something mad because you can.

Better still, maybe you not only want to do something mad, but you're also an engineer who has previously built other bikes before, and you decide you're going to go for a Guinness World Record. If that describes your approach to custom bike-building, then your name might just be Simon Whitelock, and your pride and joy might just be the infamous Whitelock Tinker Toy.

The completely unmissable heart of this particular custom beast is an absolutely massive 48-cylinder, 4,200cc (or 4.2-liter) engine. It's made from a total of 16 Kawasaki KH250 two-stroke triple engines, arranged into six banks of eight cylinders each. Amazingly, Whitelock has maintained that the bike is road-legal, though we're not sure how far anyone would want to ride it.

Whitelock Tinker Toy - Right Side Engine Closeup

2003 Whitelock 48-Cylinder Tinker Toy Kawasaki Custom - Engine Closeup, Right Side View

It does start and run, or at least it did when Whitelock posted an in-depth video about it on his YouTube channel several years back (which we've linked in our Sources). We'd embed it here, except that Whitelock has disallowed embeds, so you'll have to click through and watch it from the link. (It's totally worth it, and it's under 10 minutes long, so take a break and take a look. You also get to hear it run at the end.)

He gives several details about the engine and build in the video, which are fascinating to hear directly from the engineering brain behind the thing. Two key pieces of information you'll learn are that a) he used another single-cylinder Kawasaki 125 engine as the starter motor (or 'donkey engine,' as he describes it), and b) it weighs a massive 600 kilograms, or about 1,322 pounds. So, um, you definitely don't want to drop it on yourself.

Whitelock Tinker Toy - Front Right Closeup

2003 Whitelock 48-Cylinder Tinker Toy Custom Kawasaki - Right Side Closeup Angle View

Several pieces besides the engine parts were taken from donor Kawasakis, but generally required extensive modification to make them fit the frame. What looks like the tank cover isn't one, but it's certainly convincing from the outside. The tail came from a KH250, but had to be expanded by about an inch and a half in the middle to make it work. 

Some parts came from other existing bikes, such as brakes and a front end from a Honda Gold Wing, and a BMW gearbox. In all cases, though, they had to be heavily modified to fit the specific needs of the project, and only provided a starting point from which to work to engineer this monster of a bike.

The Whitelock Tinker Toy Is About To Go Up For Sale, And You Can Buy It

Whitelock Tinker Toy - Right Side

2003 Whitelock 48-Cylinder Tinker Toy Custom Kawasaki - Right Side

Whitelock Tinker Toy - Left Side

2003 Whitelock 48-Cylinder Tinker Toy Custom Kawasaki - Left Side

Further proving that you never know what will show up at big motorcycle auctions from year to year, the 2003 Whitelock 4.2L 48 Cylinder Tinker Toy is about to go up for sale in April 2024. The Bonhams Spring Stafford Sale features noteworthy and sometimes one-of-a-kind motorcycles every year, and 2024 is no exception. The 2024 Spring Stafford Sale is scheduled to take place during the weekend of April 20, though it appears that pages previously available regarding some of its upcoming listings have now been hidden.

Not many details are included in the listing (or were when it was live for a brief time), other than not very helpful three-word description that reads, "Offered with key." The current estimated price for this bike is between £40,000 and £60,000, or about $51,000 and $76,000 USD. 

It's an impressive feat of engineering, no question. Do you want to ride it? That's a pretty big question, honestly. At least it has a center stand?

Gallery: 2003 Whitelock 4.2L 48 Cylinder Tinker Toy Custom Kawasaki

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