Japanese air-cooled inline four-cylinder engines are a popular choice for custom builders but rarely are they as perfectly formed as this supercharged CB550 from Popbang Classics

Supercharged CB550 by Popbang Classics

It seems as if no production engine is out of bounds for custom builders and that is exactly as it should be. The huge choice of engines allows the custom builder to find the right layout to match his vision or, alternatively, build a bike around the architecture of a particular engine.

I am constantly in awe of the talent of custom builders around the world: to take a bike or even a part of a bike and repurpose it into something completely different is an art that too few people possess, even if it might seem that the custom scene is burgeoning at the moment.

There are a few custom workshops that, no matter what they are working with, it always turns out spectacularly well. Popbang Classics from Australia is one such workshop and this one, a Honda CB550-based cafe racer with a supercharger bolted on for good measure, really stood out. Popbang call it the Zeblower!

The engine and petrol tank are about the only components that haven't been custom-fabricated and the attention to detail on the whole bike is such that, the more you look, the more you notice. From the super-clean clip-on handlebars, to the hard-tail rear end, from the girder forks to the twin velocity stacks in spun aluminium, from the 21" spoked and brakeless front wheel to the supercharger installation, everything is perfectly formed.

The exhaust headers are particularly eye-catching, as is the one-off hand shift mechanism. Oh, who am I kidding, everything is perfectly executed and integrated seamlessly so it all looks as if its meant to be there and not added as an afterthought.

Right here, I'll admit that I'm no fan of early mid-capacity Japanese four cylinder engines - ultra smooth and gutless with very little character. But I confess to be fascinated to see what the addition of a supercharger will have done to the performance and how that girder-forked, hardtail rear chassis will handle.

Depending on which side of the engineering fence you sit, the phrase, 'if it looks right, it is right' will have you either nodding in agreement or shaking your head in despair. I'm definitely on the side that says, 'looks right, is right.'

It's just a shame that Popbang Classics are in Australia, otherwise I'd be round there like a shot, discussing my next build.

The amazing pictures of this bike were taken by Kenny Smith