Double driver
£150

Following Ritchey and Cannondale’s lead, Middleburn have developed a double chainring with 29 and 42T rings. The neat three-arm inner ring also acts as the spider and locks into place on the back of the splined crankarm with a lock ring. There’s a tiny amount of lateral flex under maximum big ring power, but shifting between the ‘gap tooth’ rings was dependable and immediate, with a triple shifter giving more trimming options to stop rubbing across the wide chain line. Even in deep filth we had no chainsuck problems. The 29/42 on a 11-32 cassette drops you to the point where walking is faster and the wider ratio between front rings mean a single front change has the same results as a triple front and rear change.

Upgrade for existing RS7 owners:

• One-piece spider and outer ring costs £60,
• 29-tooth £30,
• 42-tooth £35.

Verdict: Excellent weight-saver for aggressive XC riders
Rating: 4.5/5

From Middleburn 01420 23832