I've installed two Wossner pistons, 1mm oversize, and 2mm oversize, both high compression (11:1 CR). No issues. Must burn premium at all times. These pistons work well, more power, zero oil consumption, an excellent alternative to JE for the KLR.
There no fucking way this piston fits my klr 650 got it fkn bored and sleved locks up when installed piston to fuckin high valve cut outs wrong place even gudgon pin housing hits crank what a big fuck around your pustojs are shit try he for you fkn sell it totally fucking pist off