You’ll need the UDC bearing adapters. You’ll get the pick the bearing size you get with the Profile hub if you order from UDC. You can choose either a 40mm OD bearing or 1-5/8 inch OD bearing. Get the bearing adapter to fit whichever bearing size you decide on.
The Profile hub comes with the flush mount Profile Bitchin’ Bolts.
I ditch the cone spacers and just go with extra of the washer shaped spacers. Ask for extras of the washer shaped spindle spacers to take the place of the cone spacers. Extra spindle spacer washers are cheap and more convenient and cleaner looking than the cone spacers.
The hub comes with the hub body and axle, two bearings, two cone spacers, a handful of spindle spacer washers, the Bitchin’ Bolts, and the Profile crank removal tool. The Profile crank removal tool is mostly useless and potentially damaging to the hub. Use the Evercraft bearing puller to remove the cranks instead.
And buy some anti-seize so you can grease up the splines before putting the cranks on. And anti-seize the threads of the Bitchin’ Bolts too.
The pictures below of the parts came from Dans Comp.
You might want to consider a KH setup. Have you read this?:
Second, the KH/Onza hub:
Profile hubs have an effective, simple design that works OK, and they are pioneers in that they were the first mainstream manufacturer to make good splined unicycle hubs. But…they can be improved in several ways:
Profile splines are strong but prone to creaking due to manufacturing variations and wear and tear. The KH/Onza axle has a tapered section on each end, with a split washer that expands to compress the crank against the axle. Like all systems this requires maintenance (greasing) of the splines, but is an effective solution.
As Roger said, flange design makes a big difference for rim strength. The KH/Onza hub has a much better shape than any other uni hub for rim stiffness and strength, and for minimizing stress on the spokes. High-grade (7000 series) aluminum is much, much better for supporting spokes than steel flanges, such as those on D.M. or Koxx hubs. That is the big disadvantage of welding steel flanges to a steel hub.
The hub-axle connection KH/Onza is totally new for unicycle hubs and by far the best available. Profiles (and also the 2004 KH hub), used a keyway slot, which is weaker and prone to loosening and manufacturer defects. Each 7000 series Aluminum flange on the KH/Onza is machined separately and attached to the axle with the same splines as the cranks. This is way stronger and much lighter because it removes material from the centre of the hub (the centre of the KH/Onza hub is hollow except for the axle).
Third, the cranks:
There will always be debates forever on the advantages/disadvantages of Aluminum versus Cromoly cranks. Aluminum is a lighter metal but the cranks aren’t necessarily lighter because the cranks are typically solid (except for hollowtech bike cranks), whereas Cromoly cranks are hollow (KH/Onza and Koxx crank arms are the same weight).
Aluminum is stiff but may be prone to snapping, whereas CrMo typically bends before it breaks- a good safety factor. CrMo may also be more durable to extended hard impacts, like we have on unicycles. Koxx cranks are smooth on the outside but also have no Q-factor (outwards flare), so they are actually more prone to hitting your ankle bone than the 2005 KH/Onza cranks. The shortest Profiles are 145mm. In my opinion this is too long for trials. 140mm is better for rolling hops, you are less likely to hit your pedals on the ground, and they are less likely to throw off your balance when pedalling along narrow beams.
Hopefully this info answers some of the questions out there.
I read Kris’s comments and soon after I started thinking about selling my profile wheelset and moving to the KH wheelset for trials, but I cooled my jets when I found out cranksets are more or less the same weight. But the 140mm cranks still interest me.
My profile wheelset was in good shape too, selling it used would have covered a new kh wheelset, easily.