I have experimented with a couple of versions of lithium ion cell batteries but with the possible overcharge conditions this may not be the safest route. Has anyone tried the smaller led acid battery YTX5L-BS from the WR 250. It is only 1.25 lb lighter but every bit helps. The CCA is quiet a bit lower. This seams like an easy try for the guys that own both bikes. Let me know what you think.