I use allen bolts cross drilled for lock wire on B & M series oil pumps. This allows you to just nip up the bolts without distorting pump body. Also makes it easier for removing anmd refitting pump with engine in bike..
Dave

Thanks. Have lock washers on mine. Just wondered if it was common practice. Will do chain case. What size wire is usual. 0.4mm or maybe 0.6mm?

Paul C

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