Londonfixiebike ISO Cog review

Fixed sprocket for disc hubs

Our rating 
4.0 out of 5 star rating 4.0
GBP £15.95 RRP | USD $36.00
Londonfixiebike ISO Cog

Our review

Niche but nice; could be useful for expedition tourers
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This sprocket (cogs mesh with other cogs) bolts to the ISO (six bolt) disc mounts on a mountain bike hub in place of the brake rotor. 


With a 135mm wide frame/wheel, you can then flip the wheel to get a fixed gear; you may need washers to tweak the chainline. With a narrower frame you’ll need a re-spaced front disc hub – which LFB sells. Why not just use a normal fixed rear hub with a lockring? 

The main advantage – apart from the secure fitting – is that in 135mm frames it allows unusual flip-flop combinations. You could have a fixed cog option for your singlespeed mountain bike, for example. Chain tugs help.


The ISO Cog comes in 1/8in and 3/32in in 16-19T.

Product Specifications


Name ISO Cog
Brand Londonfixiebike

Manufacturer's Description Mounts onto any standard 6 bolt disc-hub to convert your bike into a fixed wheel.
Sprocket Tooth Size 16 17 18
Sprocket Sizing 3/32 In