Most of these issues have to do with the loco speeding up and slowing down on grades, and also the tendency of the loco to freewheel down a steep grade with a train behind it and the throttle off. These are certainly valid concerns and they do occur. Whether they’re cause for determining the gearbox to be “wrong” depends on what you think should be “right.,” and how you run your locomotive.
Like you, I never experienced any behavior with this loco that I hadn’t seen exhibited in many other locos in my collection. My dad’s got 4% and steeper grades on his railroad, so I’m used to seeing locos bog down and take off on steep grades. In my opinion, it adds to the realism of running the loco. (I’m not a “hands off” kind of operator. I have a wireless throttle for a reason–I want to drive the train!) I run my K in what appears to be a similar environment to yours–fairly short trains and shallow grades. I never noticed any objectionable behavior with the loco, in fact it was one of my better performers out of the box. When switching on my shelf railroad in the workshop, it would just c-r-a-w-l right along–so slow that the Kadees wouldn’t couple, they’d just push the other car away. When running at shows with 10 - 12-car trains and no grades, the loco performed flawlessly.
Having said that, I installed one of R&K Products’ reduction gearheads in my K for a product review, and did find it to have certain advantages. For starters, the loco still crawls along nicely, but does so at an even lower throttle setting. It’s still smooth-as-silk through the entire speed range. I have noticed an improvement in how the loco deals with twigs and other obstructions in flangeways, etc. With the lower gear ratio, the loco had a tendency to bog down or stop at those obstructions at lower speeds, where now it’s more prone to ride up and over them. These are noticeable improvements, but it comes with a price–gear noise. The stock gearbox is nearly silent. The gearhead has a noticeable whine to it. In most cases it’s drowned out by the sound system, and blends in from 15 or so feet away, but it is present. If it were my money, I’d look at how I run the loco. If there’s nothing objectionable about its performance relative to how you run it, stick with what you got. It’s a solid drive that performs very well. If you think it runs away a bit too much on grade for your tastes, then the replacement gearhead will mitigate that.
Later,
K
