For both hill climbs and timetrials I have been tempted to run a single chainring in the pursuit of a few marginal gains. From an aesthetic point of view it also looks good. The only downside is a potential risk of chain unshipping and undoing any marginal gain you may have benefited from. Therefore, it is not just about taking everything off; you need a sufficiently good mechanism to stop the chain unshipping. Also, the loss of gears are a problem for some courses and training.
The important thing for running a single chainring, is to make sure you get a chainring designed for single chainring use. A specific chainring will:
- Lack ramps and pins (which help with shifting).
- Also its teeth are taller its geared counterparts, which aids in chain retention.
- Narrow-wide chainrings have alternating widths between teeth to help with chain retention.
Even, if get a specific single chainring, you might still want to consider a chain guard (e.g. front derailleur / chain catcher) to be 100% sure against chain slip. Though opinion is mixed. If you have a special single ring use chainring – some will say you don’t need a chain-catcher, others will say ‘better safe than sorry’. Continue Reading →