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Typical spark output for an R12 magneto?

Posted: Wed Jan 03, 2018 10:23 am
by pkrpkr
Anyone have some directions for what is a good spark for a D2B RS172 Bosch magneto in an R12? Reason to ask is that starting is difficult because I can't kick hard enough - the new pistons have much more compression than the worn out old ones :-)
At 50 revs/min at the magneto, the spark can bridge about 2mm, at 100 revs/min at the magneto spark can bridge 7-8mm in open air. Is that good enough?
Thanks,
Peter
PS bike runs fine at idle once it's started