Not sure where else to post this, but I feel like people here would have the answer.
Most IKP trucks have a well-known problem of loosening-up on their own. Why? What about the design is constantly "faulty?" Why do regular kingpins not have this problem.?
Also, Ace claims they have designed an IKP that solves the issue. Does it? What did they do differently?
@Mbrimson88 what you got on this one?
On my way...
Ok, so before getting into the main part, I have noted that inverted kingpins have two things going on, not only the little bit of side to side movement of the whole kingpin when it is not hard pressed into the baseplate, but also the baseplate hole for the kingpin can end up ovalling out and at worst case coming apart due to the kingpin moving so much if people are applying so much pressure, especially from heavy angled landings, eg crooks or feeble / smith grinds.
As to the kingpin loosening on its own, this is down to the nyloc on the nut either wearing out or not fully engaging the kingpin, which might seem strange, but I have seen people not tighten their inverted kingpin nut down far enough so the thing is basically finger tight, almost like having the nut only half on there.
From my own experiments, I have only had inverted kingpins move or come loose when the nyloc has been worn out, on some used inverted kingpin trucks that it seemed the previous owner swapped out bushings every other session. My own inverted kingpins on Indy, Thunder and some other brands have not moved at all in the whole time I have had them, but I am more the sort of person who will ride trucks from new, adjust as needed during the bushing break in period and barely touch the kingpin for the life of the truck, unless something happens and I need to put in new bushings, but again, then just a little adjusting and then left without constantly fiddling with the kingpin or kingpin nut.
Also I think it is important to note here that I have seen repeated hollow inverted kingpins of almost every brand break, so no matter what tech or whatever else is going on, if it is a hollow kingpin, some people are going to have issues with them, while others might never have any problems.
This includes Thunder, when they first came out with the hollow kingpin, then changed to the solid kingpin and I haven't seen any issues since. Other people have posted the new Ace hollow inverted kingpins in pieces, Slappy hollow inverted kingpins snapped, including the Ultra low versions, etc.
The Indy / Krux current solid versions are said to have a lifetime warranty against breakage, so although they don't have a lot of threads, I have machined them so that they can now fit in Thunder and other inverted kingpin trucks, which require more threads, or have a longer threaded shaft in the baseplate.
There is also a newer version of Indy that I have not seen, which is said to be better and sort out previous issues, but I will wait and see on that one.
For me, besides the Thunder hollow kingpin breaking, all the others, including my own DIY inverted kingpins have not come loose at all and my little bottle of Loctite is still sitting here unopened, which I bought to experiment with after seeing so many issues with inverted kingpins coming loose.
Maybe I am just not as hard on my gear as most people, or don't touch my inverted kingpins once they are set up, but I think overall inverted kingpins get a bit of a bad rep more so because people are always touching or changing things on their trucks, bushings, or skating harder than the product can hold up.
This was definitely the case with the Indy inverted truck assembly when it first came out, with a couple of people I know destroying theirs fairly quickly, whereas the set I had kept and used are still fine to this day.
* Ace has a lock in place kingpin, so a kingpin with three grooves down the shaft and a locking mechanism built into the baseplate, which by all accounts holds the kingpin nicely, but as they are hollow, they do break on some people, so there is that to bear in mind.