Yeah that'd do the trick, just not really ideal unless he gets a faceplate style stem, the old school clamp ones will prove a ******* fiddly job I think.Stem Spares - Handlebar Shim
Handlerbar Shims Black anodised alloy. Various sizes; 25.4 - 22.2mm - for BMX to MTB stems 26.0 - 31.8mm - for Standard Road size to 31.8mm oversize 25.4 - 31.8mm - for Standard MTB size to 31.8mm oversizewww.bing.com