To get a neutral flame on a Minor burner, you want to look for nice
sharp blue "candles" at the base of the torch flame. It shouldn't be
hissy-sounding and shouldn't have soft orange flames at the base. A
hissy flame is oxidizing (very useful with some borosilicate
colors), a bushy orange flame is reducing (which will muddy or bring
up the metals in some colors).
Be warned, a Minor is much cooler than a Red Max, so you're going to
be working a LOT slower than you have in the past. Working boro on a
Minor isn't impossible, but it's not speedy either.
I nice "compromise" torch, IMO, is the Midrange Plus with a
topmounted pre-mix (similar in function to a National 3A). The
premix is quite hot for basic melting and shaping, and the Midrange
gives you a nice-sized but softer flame. I have a Midrange and find
it to be very versatile. I can work anything from taffy-soft Kinari
and Satake all the way through 1" solid boro rod.
Feel free to email me at desertdreameraz at cox dot net if you have