Glad I stumbled upon this thread. I play an Ibanez SRC6MS with the nut and bridge modified to accommodate a custom assemblage of .120–.030 GHS bass and guitar strings for B0–B2. As it has become a go-to instrument for me, I have considered replacing the serviceable stock tuning machines with locking Sperzels. Those claim to take up to .125 with no need of any taper to the string, which would really open up my options for strings; but based on what I’ve read here, I would want to check with Sperzel to see if they can handle diameters down to .030. I wonder whether some constructions of strings would slip in the locking mechanism less than others at lower diameters
Also glad of course to hear that these strings worked out well for your unique situation! While it wouldn’t likely save you anything on cost, you could consider ordering four singles in the diameters you prefer; at least you wouldn’t find yourself stuck with two superfluous strings with every change. You might even like this set from Rotosound.
My experience with the bass Sperzels is they can definitely accommodate up to a .125
As for the thinner strings, the EB .30 roundwound didn't even stand a chance. It wouldn't just pop out mid tune, I couldn't even get a tweak of tension before it just slipped out. I doubt other rounds would stay gripped if these EB rounds couldn't. Very coarse steels may stand a better chance, but it's a gamble. Now, you could in theory just wrap/tie the string around the post to get around this, but guitarists all over the net vehemently insist you'll have terrible tuning stability by doing this. Not sure it's worth the risk for your Ibanez VI.
