Surly Mr Whirly crank arms review

Highly versatile

Our rating 
3.5 out of 5 star rating 3.5
GBP £120.00 RRP | USD $192.98
Surly Mr Whirly crank arms

Our review

A nice piece of kit, but this much adaptability doesn’t come cheap
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The appeal of Surly’s modular crankset is that it can be configured to suit any bike and there’s a good choice of Surly or Salsa chainring/bashguard combos. Like most Surly products it’s cautiously overbuilt to take a fair amount of punishment. 


But this much versatility doesn’t come cheap. By the time you add a couple of rings and/or a bashguard to the crank arms (£120), spider (£65) and axle (£60) you’re looking at about the same price as the complete triple setup (£320), and you still need to buy (Shimano cup compatible) bottom bracket bearings.

The weight of our 33/22-tooth, 175mm arm double setup is fairly reasonable considering the fact that we used a stainless steel outer ring. A hefty chromoly steel axle emphasises Surly’s design attitude: this is a crankset that’s intended for heavy-duty cross-country use and a long multi-bike life, and our experience is that it does the job.

Bear in mind that while the five-arm spider offers a good choice of rings from sister brand Salsa as well as Surly, most other cranksets these days are four-bolt.


This article was originally published in What Mountain Bike magazine, available on Apple Newsstand and Zinio.

Product Specifications


Name Surly Mr Whirly crank arms(12)
Brand Surly

Description Weight: 760g with two rings, BB axle 145g, Lengths: 170mm, 175mm (tested), 180mm
Weight (g) 951
Material 7075 T6 Aluminium Alloy Chromoly Steel
Chainring Size (No of Teeth) 22 32 44
Crank Arm Lengths 170mm 175mm
Chainring Options Single Triple