Forget metric – when describing folding bikes, the cognoscenti usually resort to the imperial wheel size, as in: ‘8-inch folders are rubbish’, ‘16-inch folders are compact’, or ‘20- inch folders are faster on the road’, etc, etc. As a general rule, if you’re looking for out and out performance, you’ll need a 20-inch, or more accurately 406mm (or occasionally 451mm) folder.The really sporty 20- inch machines are mostly ‘demountable’, taking apart for air travel, although they usually include a quick-fold feature as well.

Thanks presumably to the airline connection, this market is dominated by US companies, such as Bike Friday, Gaerlan, and PBW, with a solitary Union Jack being waved by Airnimal.

We tested a PBW Road Bike back in A to B 20. Although nominally available in Road, Trekking (like Road, but with flat bars) or MTB versions, in practice you can mix-and- match just about any components you like – one of the advantages of dealing with a small manufacturer.Thus time we’re looking at one of the most expensive variants – a Trekking model with front and rear suspension and 14-speed Rohloff hub.

Like most high-tech US folders, PBWs are custom-made, so if you order one, it’s guaranteed to fit.The custom-built machine arrives with an adjustable stem – during your first weeks of ownership, you fiddle around with this until you’re comfortable, mail your vital statistics back to PBW, and the company makes you a personal stem. Now isn’t that a good idea?

PBWs start at under $1,000 in the US, but thanks to the bits and pieces, ours costs a rather weighty $2,500, or close to £2,500 including duty,VAT and delivery to the UK.

The Rohloff

The Rohloff Speedhub is an interesting beast if you like that sort of thing.The German manufacturer started life producing bicycle chains and other components before taking the brave step of developing, building and marketing a unique 14-speed hub in 1998. An astonishingly complex bit of engineering, the Speedhub offers a number of advantages over more conventional gears: Firstly, the ratios are evenly spread, so the 14- speed hub offers a similar range and flexibility to a typical 27-speed derailleur system. Without a derailleur, there’s (usually) no need for a chain tensioner, so ground clearance is not compromised (particularly important with small wheels), and with the moving parts safely sealed in an oil bath, life expectancy should be more or less infinite.That’s fortunate, because the key disadvantage is a price tag of around £600 in the UK. According to Rohloff, there’s no weight penalty, because at 1.7kg, the Speedhub is similar in weight to most 7-speed hubs and the complete system is only 200g heavier than a comparable derailleur.

A little more controversial is the question of efficiency. Rohloff claims a figure of 95-98%, but independent research (see A to B 27) suggests a figure closer to 90- 91%. Rohloff later telephoned to offer some complex counter- arguments that we simply can’t go into here. Suffice to say, they disputed the figures.

What do we think? We’d say there was some loss of efficiency over a well-maintained derailleur or a simple 3-speed hub, but it’s certainly no worse than a typical 7-speed and smoother than some.The hub does exhibit quite a bit of drag though, and it’s enough to spin the pedals when coasting.This might explain why the PBW managed only 14.1mph descending our test hill. For a 20-inch bike wearing 32 x 406mm Schwalbe City Marathon tyres, that’s on the low side, suggesting that there’s enough drag to take the edge off fast descents.

Riding a Rohloff-equipped bike for the first time is a strange experience.The gears click smoothly in and out of engagement as one might expect, but if you start at the bottom and work your way up, they seem to go on for ever.With a total range in excess of 500%, the Rohloff really does offer a gear for every eventuality, and unlike a 3×9 speed derailleur, you can find the right cog by turning a single twistgrip, although the change is a bit heavy and notchy.

Unusually, the twistgrip is linked to the hub by twin operating cables, rather than a single cable and return spring like most hubs.When you change up, one cable pulls the hub into gear while the other trails – and visa versa when you change back down. Another unusual feature is that the ‘detent’ notches are in the hub itself, so it’s impossible for the cable to go out of adjustment and try to engage, for example, gear 21/2.The cables will slacken with age, (there’s a tension adjustment to deal with that), but it won’t  miss a gear provided the cables move  reasonably freely.The rather stiff clicks you feel when turning the twistgrip are the gears actually engaging at the rear end.

…the hub starts quite smoothly, but becomes progressively rougher up to gear seven…

In practice, it is possible to provoke a slight graunch if you pedal too hard through the change, or do something equally clumsy, but as a general rule you top it up with oil, tighten the cables and forget it. Exactly as things should be.The only evidence that complicated things are happening in the hub is a slight difference in ‘feel’ between the gears. Looking at Rohloff’s charts and the independent efficiency figures, it turns out that this vague feeling is backed up by what’s actually happening inside the hub.

The Speedhub starts quite smoothly (and efficiently) in 1st gear, but becomes progressively rougher (and less efficient) up to gear seven. Thereafter a magic transformation takes place, because gears eight and nine are silky smooth and amongst the best efficiency wise, but engage the bigger numbers and it’s downhill all the way to top, where things get relatively rough again.

In practice, changes can usually be made under load, but that transition change from rough seven to smooth eight and back takes special care. After a bit of practice, you begin to treat the gears as two separate blocks of seven. Pass between them too rapidly, or while pedalling, and the hub tries to engage seven and eight simultaneously. Ouch! What we don’t know, after an acquaintance of only a few weeks, is whether the components would eventually ‘run-in’, making things smoother.

According to Rohloff’s technical literature, the hub contains three epicyclic gear sets, with the individual ratios making use of one, two or all three of these sets, with direct drive in gear 11. Obviously the more cogs that are involved, the rougher and less efficient the result, although strangely enough, we rated gears eight and nine smoother than gear 11 (direct drive) even though they both use a single epicyclic set.

Are we being ultra-critical? Well, we’d be a lot less demanding if the hub cost fifty quid rather than 500, because the last thing we want is for you to fork out a year’s savings and be disappointed.To sum up, the Speedhub is no doubt capable of running for a lifetime with no more maintenance than a few drops of sewing machine oil once in a full moon, but if you’re the sensitive type who insists on a sewing machine ‘feel’, you might find cause to grumble.

On the PBW, the ratios are close to perfection – evenly spaced between 19″ and 97″. A shade low perhaps, but few cyclists would argue with that sort of range.The only real disappointment is the graunchy change between eight and seven.With ratios of 45 and 40 inches you’ll be making this change whenever a moderate hill turns into a steep one, and this slow change doesn’t help. But, to be fair, derailleurs suffer from all manner of awkward changes too.The Rohloff has just the one fault.

It’s widely accepted that Americans have softer bottoms than Europeans…

Suspension

It’s widely accepted that Americans have softer bottoms than Europeans.Why else would they design such things as Harley-Davidsons, Cadillacs and floaty air suspension units on bicycles? British derrieres, honed by suspension-free Mini Coopers, unsprung bicycles and indifferent furniture, are made of sterner stuff. OK, that ignores such unsprung US products as the Bike Friday, and softly-softly Brit offerings, like the elegant Moulton… But there seems to be a general hard/soft divide.

All PBWs feature Cane Creek air suspension at the rear with the option of Ballistic elastomer forks at the front.The rear suspension is really little more than an air reservoir – the pressure can be adjusted, but there’s no damping adjustment. In fact, there’s no damping at all, other than friction in the mechanism, although pricier units are available, offering various levels of sophistication. If you have a decent pump with a Schraeder valve, it’s possible to set the pressure, but beyond 120psi or thereabouts, the unit locks up completely, presumably due to internal friction. So the choice is either a relatively soft wallowy ride, or dead firm. If you’re not used to pedalling smoothly, you should choose the latter, because an aggressive pedalling style with low air pressure simply makes the back of the bike pogo up and down.

The front elastomers are controlled by a pair of rather vague adjusters that appear to add stiction as you twiddle. In practice, we set them soft when the rear was soft, and sticky when the rear was rock hard.

We wouldn’t dare say anything clever about spring rates or rebound damping because we couldn’t detect such niceties – just soft or hard. On ‘soft’, the bike will go places 32x406mm tyres were never intended to go without tripping over the boulders, and on ‘hard’ you can pedal any way you like without bouncing out of the saddle. It’s nice to have the choice, but we’re not convinced we’d want to pay much extra for it.

Folding

If you’re used to dismantling the bigger, sportier kind of folding bike, you’ll love the PBW, but if you’re expecting Brompton-style performance, you’ll be disappointed. It’s actually quite similar to the Brompton – even sharing the same frame hinge.The frame folds to the right, the rear triangle underneath and the saddle stem locks it all together, but it’s a much sloppier performance and you have to remove the stem and strap it to both wheels before you can walk away. That said, the PBW is quicker than the Bike Friday – and arguably easier than the Birdy in Not some respects, thanks to its constant chain the length.The end result measures 84cm x 83cm x neatest 38cm or 265 litres, which in good old imperial equates package in the world, but at 265 litres, the PBW to just over 9 cubic feet. As the suspension forks add a packs small for this class of bike bit of width, and a left-hand folding pedal would help, our figures should be treated as a worst case scenario. Not bad for such a sophisticated package.The bike is also designed to fit inside a case measuring 74cm x 56cm x 28cm with the removal of a few bits.

Weight, at 13.4kg (30lb), would be enough to put some people off, but that’s the downside of suspendy bits and 14-speed hubs.The basic PBW is not a heavy machine.

Conclusion

We like the PBW. It represents a good compromise between foldability and performance, neatly filling the gap between the Birdy and the Bike Friday. What’s more, PBW is a small outfit, so you can expect personal and helpful service. Our conclusions on the Rohloff were less clear – we think there are too many gears, they’re too close together, and of variable quality. It’s a great idea, but the consensus was that a smaller, lighter, wide ratio seven speed hub would be better.

Suspension? It’s nice on a mountain bike, and jolly useful on a utility get-to-work bike, road surfaces being what they are, but we like our sporty bikes lightweight, lithe and simple.We would certainly put a PBW on our shortlist, but we’d keep it simple and go for one of the cheaper models.

Specification

PBW Road Bike $2,495
Weight 13.4kg (30lb)
Folded dimensions W38cm H83cm L 84cm
Folded Volume 265 litres (9 cu ft)
Gears Rohloff 14-spd hub
Ratios 19” to 97” (in even steps)
Brakes Cane Creek V-brakes + SRAM 7.0 levers
Tyres Schwalbe City Marathon 32-406mm
Front Suspension Ballistic forks (polymer)
Rear Suspension Cane Creek AD5 (air filled)
Manufacturer PBW tel +1 530 566 9699 mail info@PBWbikes.com web www.pbwbikes.com