I’ve been asked this many times now, but have only just finalised my setup for my 24 Hour and 12 Hour world records.  The original plan had been to use a V-frame time trial unicycle, custom built by C3 cycles. Unfortunately, when I received the instructions from Guinness, it seems that will not be acceptable: 

“The unicycle must be a commercially available, unmodified model. Full details of the unicycle used must be submitted”

“The same unicycle must be used throughout the attempt. Repairs may be made, but the unicycle must remain the same.”

So much for that. 

Wheel

I decided pretty early on to ride my carbon Braus 36″ wheel with the nightrider lite tyre and TPU inner tube. It’s a very light and fast rolling setup.  I also ordered a Mad4One unicorn carbon 36 wheel with the T-monster tyre to try.  In testing, the Mad4One wheel is very strong, and probably better suited to gravel/off road riding, but has higher rolling resistance on concrete than the Nightrider/Braus rim.  The speed and rolling resistance improved as the knobs wore down, but is still slower than the Braus rim.  It is comforting to have a spare wheel though- I interpret the Guinness guideline to allow a wheel change when they state ‘repairs may be made’.
The problem with my Braus 36″ wheelset is that it is inherently weak. With 32 spokes, and built on a disc hub, the flanges are close together, which is not great for strength.  The spokes loosened up after just 300km riding. Like…wiggly loose.  I was very worried about this wheel, and even considered rebuilding it with a wide hub.  Time was ticking, it was a month out from my record.  I took my unicycle to the top wheelbuilder in town- Wheelworks.  They suggested rebuilding the wheel with locking nipples.  So that’s what we did.   I’ve ridden over 100km on this….so far so good.

Seat/handlebar
The next most important component is the cockpit.  I have been a fan of the KH T-bar/flatfish combo, but this year I rode almost exclusively on the Mad4One handle-saddle.  They are both great setups, but I felt the stiffer Mad4One saddle is a better fit for a 24hr attempt.   With this combination, my unicycle weighs just 5.1kg!
After my 12hr practice ride, I realised the saddle, despite being as long as the KH T-bar, just isn’t long enough. I was over reaching and wishing the bar extended another 30cm.  Luckily, Marco Vitale from Mad4One had a great solution, which is an extension bar that attaches to the Mad4One handle saddle.  It attaches with a special glue and tape, but I found a time trial handlebar attachment that bolts it all together, with some cable ties to secure it fully.  Not the most elegant looking cockpit, but I left out the bar tape to allow easy bolt access.  
Riding aerobars is quite different to riding a regular unicycle.   It changes the balance axis and technique,  and I was too scared to go fast on this initially.  After a few practice rides, my top speed is the same as before aerobars. The main advantage is that my upper body is supported, which helps with fatigue.  You rely more on the upper body for steering, which allows the legs to dedicate themselves to propelling you forward, instead of controlling the unicycle.  

Electronics

I will use a Lezyne Mega XL computer to keep track of the overall time, as well as my trusty old Garmin edge 200 for lap speeds.  The Garmin is a small unit, which I can hold like a stopwatch. I normally count 12 laps to get a roughly 4.8km short distance check of my average speed.  The Lezyne will keep track of my overall average speed and distance for 24hs.  I chose the MegaXL due to its battery life….it lasts over 48hrs, whereas even the most expensive Garmin units are borderline for a 24hr attempt. 

Lights

Keeping with the Lezyne theme, my main light will be a Lezyne macro-drive 1400.  It was a toss up between getting this light or a Magicshine Ray 1600. They both have the same capacity battery, but I felt the (claimed) 450 Lumen setting on the Lezyne which lasts 12 1/2hrs is preferable to the (claimed) 400L 8hrs setting on the Magicshine. The Lezyne is quicker to mount and remove- with a rubber attachment rather than a Garmin clip, so there is no attachment in my way when the lights are not in use. Normally I’m dubious about rubber band attachments as they have a tendency to rattle loose on the handlebar, but Lezyne’s is robust and very secure.

Specs
The entire unicycle is built from commercially available parts, so should satisfy Guinness for the record attempt.  Weight (including computer) is 5.73kg.

Triton 36″ titanium frame
Alchemist Braus 36″ carbon rim
Pollici 36″ TPU inner tube
Nightrider Lite 36 tyre
Nimbus ISIS Disc 32H hub
Quax 100mm cranks
AEST Ti pedals
KH seatpost
Mad4One long handle saddle
URSLI bar extension