Don't know if you can substitute the mercury for something else on this one. The tube passages are real small and if you went with a lighter liquid, it might just get sucked into the intake. This kit warns about revving the engine above 3K RPM for that same reason.
As for the dangers associated with mercury, if handled properly, it's no big deal. Now if you eat it or are exposed to it regularly, then yes it's bad. Lead is probably just as toxic.
Chuckbear, my plan is to check the valve clearances & adjust if necessary. Figured as long as I'm in there, might as well adjust the throttle bodies, which by itself, seems like pretty basic procedure. The old lady wants a bike next year, so that'll be five vehicles to maintain. It's more cost effective to DIY, which is the primary reason I work on vehicles at all, lol.
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