Yes I had that problem with my first Novelty. So I returned that an my replacements arrived today, just finished running it in now. Although my second did have a slight jerk/tight spot, it’s sorted it’s self out after running in light engine in both directions followed my running with a heavy train.
As a note my heavy rake consisted of 7 superdetail Hornby teaks, hauled with ease. All I have to hand here as mainly our LMS stock is kept at my fathers. As a Comparison, I then removed the traction tires and tried again with the same rake, although it would pull it was struggling, so reduced the rake to 5, an it runs perfectly which is more than adequate. We’ve got various rakes of Ratio built coaches that the Precedent will run with.
Personally I did think the loco ran better without traction tires, others may have different experiences. Time to get the various items fitted that came with the detailing kit ready for taking at the club on Monday night, where will be paired with our ratio coaches