I suspect goldtec are measuring to the mounting face, not the actual chain centre line. That would explain why they are now offering 40mm, which would be impossibly narrow if it were actually the chain centre line.
@gbj_tester started
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I suspect goldtec are measuring to the mounting face, not the actual chain centre line. That would explain why they are now offering 40mm, which would be impossibly narrow if it were actually the chain centre line.