Some nice features but let down by lack of waterproofing
Birzman Zyklop Voyager stem bag
6 10

Birzman Zyklop Voyager sounds like the stuff of cult 60's sci-fi but in fact it's a double decker stem bag designed so riders can safely use their smartphones, while keeping keys, credit cards and the like within easy reach.

There are two versions, one for the iPhone 4 or ours whose 128x70x10mm dimensions fit larger phones, GPS units, compact cameras or even OS maps.

Thirty quid buys a sturdy, water repellent PVC case with transparent top moulded to a glossy, carbon effect ABS base. Retro reflective piping running parallel to the zip is another welcome feature, subtle enough by day but blisteringly effective when combined with those proliferating clothes, tyre sidewalls, mudguards etc.

Peeling back the sensibly proportioned tags reveals a densely-padded Velcro bed cum trap door for docking one's delicate devices. The bottom bunk boasts similar refinement and a broad elasticated centre strap to prevent that irksome toolkit jingle. Efficient packers should manage small to moderate pocket tool, patch kit, tyre levers bank card/cash and micro pump. However, this sort of cargo requires a decent bracket and ours is already showing some signs of fatigue.

On the plus side, a choice of rubberised shims and lanky Velcro straps ensure dependable tenure to traditional and contemporary stem diameters without fouling extension brackets and similar accessories. Accessing the other compartment is faff-free with no fear of electronic gizmos falling to their death.

Unfortunately, the window prevented use of my phones touch screen, and the bag's water resistance is only adequate, as opposed to outstanding. It keeps out light to light to moderate rain, but a heavier downpour saw the interior wet within 15 minutes. That meant using the rain cover, which hides the screen, making the whole exercise a bit pointless.


Some nice features but let down by lack of waterproofing.

road.cc test report

Make and model: Birzman Zyklop-Voyager I/II

Size tested: Black

Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?

.Unique upper transparent cover pocket for iPhone (Zyklop-Voyager  28 and Smart Phone (II) ,GPS,or map

4.Interior fits tire lever,repair kits,mini tool

5.Water resistant material

6.Band clamp bracket , rain cover are included

Tell us some more about the technical aspects of the product?

.Material: ABS + eco-friendly PVC


I: 35(W)*85(L)*10 (H)mm size designed for Apple iphoe 4/4s

II: 70 (W)*128(L)*10 (H)mm enlarged size for bigger smart phones

Rate the product for quality of construction:
Rate the product for performance:
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Rate the product for weight, if applicable:
Rate the product for comfort, if applicable:
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Tell us how the product performed overall when used for its designed purpose

Overall, this little bag is a nifty way of toting riding essentials. However, the waterproof cover means smart phones, GPS and similar gizmos cannot be used to their true potential, which was disappointing.

Tell us what you particularly liked about the product

Convenient and stylish.

Tell us what you particularly disliked about the product

Fabric only water resistant.

Did you enjoy using the product? On balance, yes.

Would you consider buying the product? No, hasn't quite lived up to its potential.

Would you recommend the product to a friend? Not if they wanted to make full use of their technology.

Overall rating: 6/10

About the tester

Age: 40  Height: 1m 81  Weight: 70 kilos

I usually ride: Rough Stuff Tourer Based around 4130 Univega mtb Frameset  My best bike is: 1955 Holdsworth Road Path and several others including cross & traditional road

I've been riding for: Over 20 years  I ride: Most days  I would class myself as: Experienced

I regularly do the following types of riding: cyclo cross, commuting, touring, fixed/singlespeed, mtb,


Shaun Audane is a freelance writer/product tester with over twenty-eight years riding experience, the last twelve (120,000 miles) spent putting bikes and kit through their paces for a variety of publications. Previous generations of his family worked at manufacturing's sharp end, thus Shaun can weld, has a sound understanding of frame building practice and a preference for steel or titanium framesets.
Citing Richard Ballantine and an Au pair as his earliest cycling influences, he is presently writing a cycling book with particular focus upon women, families and disabled audiences (Having been a registered care manager and coached children at Herne Hill Velodrome in earlier careers)


mikroos [257 posts] 3 years ago

The price is just absurd. You can get ones like this for 10 quid on DX.

To me the best bag around is T-One Pokemon - as funny as its name is, it's simply a great product. Looks good, is stable, works with touch screens and costs about 10 quid. Highly recommended.