Most reasonable comments on this thread, IMHO!
Opinions on the doohickey (and the overall scheme of balancer chain slack adjustment) often take on the character of mandatory religious belief, to some!
As in, "Salvation DEPENDS upon doohickey replacement absolutely, regardless of generation!" Or, more skeptical, perhaps agnostic, views of aftermarket upgrade.
This thread contains reasonable perceptions and alternatives available for each individual to consider for his own choice; refreshing!
While I know of no Generation 2 doohickey (idler shaft lever) component failures, strong evidence suggests Generation 1 parts sometimes grenaded, and with catastrophic collateral damage.
Eagle Mike (and others) deserve great credit for developing an alternative substantially reducing the probability of this heartbreak.
Just wondering: No easy/reliable way exists to answer the question, but . . . of all the KLR650s manufactured over 25 years of production, and in service worldwide . . . what percentage have aftermarket doohickeys installed?
FULL DISCLOSURE: I have Eagle Mike doohickey and torsion spring installed on my Generation 1.