When was the last time you changed your bike's engine oil? Or lubed its chain? Royal Purple Max-Cycle ($16 per quart) exceeds API/JASO new-warranty requirements and is compatible with wet clutches. Max-Chain ($7 per 4-ounce can) is biodegradable and won't collect dirt or fling off. For bikes with non-unit transmissions, Synchromax ($14 per quart) is said to improve shifting and reduce gear noise, all while operating at reduced temperatures.