Facebook button Flickr button Youtube button

Archive for December, 2015

C3 stainless steel project

After getting back from Unicon 17, I realised that I have far more wheels than unicycle frames, and it was time to get a dedicated frame for my 700c standard racer. I had been using my 2008 Triton sponge frame, which is an amazing unicycle frame, but looks rather silly with a sleek racing wheel. It was designed for a 29’er mountainbike wheelset, and had enough clearance to drive a truck through. That notwithstanding, every time I wanted to go out for a ride, I’d be swapping wheels in the frame.

I was originally planning a titanium road frame, but with Dmitry at Triton busy with bicycles over the 3yrs I had been pestering him, I had to find a local alternative. With three titanium unicycles and a Litespeed titanium road bike, you can probably guess I am a big fan of the grey metal. The great thing about titanium is that it is strong, corrosion resistant, doesn’t need painting, and still looks great many years later. It is also hard to work with, which is why there are few ti builders around.

So with a bit of research I came across the new stainless steel tube sets being used on bicycles. Most of the bicycle tube manufacturers are making them, and they are perfect for custom bike frames. As yet, though, I am not aware of any stainless steel unicycles. Stainless steel doesn’t need painting, is light, strong, and, in my opinion, looks even better than titanium….I would be swapping grey metal for the shiny one.

I looked up several frame builders in New Zealand, but settled on Anders Waiker at C3 (crucial custom cycles) in Petone, not far from where I live. It meant I could pop by during the week to sort out any design issues. He makes some beautiful mountainbike frames, so I was keen to work with him.

We decided to use the KVA MS3 tubeset, which has a built in curve for a bicycle chainstay. We thought the s-bend would look pretty cool on a unicycle. It took a few weeks for the tubes to arrive from the US, but here they are:

KVA MS3 Stainless Steel Tubeset, ready for welding

Now you’d think a unicycle frame is a fairly straight forward thing to build, but once you add in curves it becomes a bit more complicated. Luckily, I could bring in my 700c wheel to slot into the frame to help with measurements, because my framebuilder is local.

We had less clearance than expected, which meant that Anders had to crimp the legs slightly. On the other hand, the s-bend gives heaps of foot clearance, which is vital to anyone who races standard class.  You want your feet as close to the frame as possible to maintain a high cadence, but you don’t want your feet hitting the frame either. An added bonus of bicycle tubing is you get the special things they do to bicycle tubes, such as double butting. These tubes are superlight!

Anders fillet brazed the frame, giving it a smooth seamless appearance. Check out the seat-tube and fork leg interface:

Sexy curves

The fork was completed with a mirror finish (it took Anders 3 days to polish it!), and sent off for painting. Unfortunately the painter had undergone hand surgery, so it took a couple of months to get it back.  Anders topped the frame off with a very nice Thompson seat clamp.  

The complete specs are:
Nimbus Eclipse hub
Wheelsmith SS spokes
Mavic Open Pro rim
Schwalbe Kojak 700x35c folding tyre
Nimbus Venture 89mm cranks
Welgo M111 pedals
Kris Holm seat post
NNC Flatfish saddle

Total weight is 3.410kg with the above specs. I did some swapping of components (75mm nimbus cranks and 700x23c Rubino Pros), and swapping seats (my other Flatfish saddle uses lighter foam), which brought it down to 3.133kg. Not far off a sub-3kg unicycle, which should be achievable with a few component tweaks. 

So how does it ride? Unlike a bike, the frame has less influence of the ride than the wheel itself. The main requirements are stiffness, particularly on climbing and cornering, adequate clearance, and lightweight.

I’m pleased to report the C3 stainless racer performs well on all three counts. I jammed it up the steepest hill I could find, which would normally flex any unicycle frame. Despite trying my hardest, there was no rub at all, even with the small clearance between the spokes and the frame.  It corners like a dream, tracking exactly where I point it, even when driving hard into a turn.

The s-bend stiffens the frame and gives oodles of room to get my feet close to the midline without rub. Not a big deal for most riders, but for anyone spinning over 160rpm, the last thing you want is to hit the frame with your foot. Weight-wise, the frame is comparable to the Tritons at a shade over 600g. Although the butted stainless steel tubes are lighter than titanium, the bearing holders on the Tritons are quite unique. As a result, the C3 frame is weighted toward the bearing holders, which gives it a lower centre of gravity- not a bad thing.

Although I built the unicycle as a racing uni, most of the time…it won’t be. That means no excuse for wearing lycra either!  Baggy shorts are not a good combination with unicycle frames, they tend to snag on the fork crown.  With the s-bend C-3 racer, I can ride my unicycle any time, anywhere, and not worry about ripping my shorts to bits.

Oh yeah, did I mention it looks cool?

P1080692 P1080572 P1080590 P1080675

Our Alps 2 Ocean Unicycle Trail video

Alps to Ocean Cycle Trail

Alps to Ocean Website

Our Photo Album

I flew down to Christchurch on Labour Weekend to meet up with Anna, who had been busy performing puppet shows in Christchurch. She had been telling me about the Alps 2 Ocean trail for the best part of the year, so we finally decided to do it together during her South Island Tour.

The new 300km trail is part of the NZ cycleway, and takes you from Mt Cook Village to east coast of the South Island. We were also going to visit Anna’s nana, who lives in Twizel, in the middle of the A2O trail. Our plan was to complete the first half from Mt Cook Village to Omarama.

It was the first time I’d been to Christchurch since the earthquakes, so after Anna picked me up from the airport we went to the city centre to have a look around. We walked through the square, gazing at the ruins and new construction. The last time I was at Cathedral Square was on our 2007 South Island Unicycle Tour, so it was quite sad to see so many buildings demolished or damaged by the quake.

We had lunch at the new mall next the square, which was built out of shipping containers. After a quick stop to pick up riding supplies at the Cookie Time factory, we set off on the picturesque drive to Twizel.

We arrived at Nanas house but she was out playing golf, so we were greeted by her Great Uncle Alec who had driven down in his camper van from Tauranga. Anna showed me her childhood hangouts in Twizel, then we picked up fish and chips to fuel up for tomorrows ride.

Day 1

“We’re doing what?!!!” Anna had slightly mistaken the geography of the area. Instead of a comfortable 60km ride she’d planned for our first day, it would be a 74km ride to Lake Tekapo, followed by a 94km ride to Lake Ohau the next day. We were starting on the regular A2O ride, but cutting across to the alternate start at Lake Tekapo.

“…but I thought Tekapo was along the way!”

Luckily having Twizel on the trip route meant we could start in Mt Cook Village and finish at Nana’s place later that day. It would still be a challenging ride, as we would be completing two sections in one day.

Uncle Alec drove us in his campervan to the start of the A2O trail at Mt Cook Village. From there the track starts off fast and flowy, a scenic 8km trail to Mt Cook Airport.  This was more helicopter landing pad than airport, as the chopper is the only way across the river unless you fancy an icy dip. The all too brief 2 minute ride gave amazing views of the mountains and river below. It dropped us off at Tasman Point, before ferrying other passengers to the glacier.

P1070918  P1080030  P1080089  P1080105  P1080116    P1080285  

From there we cycled toward Lake Pukaki, following the Tasman River, and had lunch of peanut butter sandwiches along the riverbank.  Once we hit Lake Pukaki the track turned into a gravel road, with the Southern Alps seeming to rise above it.  The lake is an amazing shade of blue, photos don’t do it justice!  

Half way down the lake we stopped at Braemar Station to fill up our drinkbottles, much to the bemusement of the farmer and his son.  It was getting really hot so we considered cooling off in the lake. Although it was a warm day the lake was anything but! After dipping our toes into the glacier fed waters we decided a swim was not on the cards.

By the time we arrived on the final stretch to Twizel, the sun was setting. Anna was getting tired so we finished our ride at the dam. Anna’s Nana picked us up and drove us back to Twizel to stay the night.

Day 2

The next day we got up bright and early and started back at the Pukaki dam. The first part of the track meandered through dry grasslands typical of the MacKenzie Basin landscape, the ‘Pukaki flats’.  It took us back to Twizel but we bypassed the town by taking the alternate ‘flood’ route. Anna wanted to show me Lake Ruataniwha, where she had spent many childhood holidays. It is an artificial lake created by another massive dam; part of the Waitaki Hydroelectric project of the late 1970’s.

There was a Salmon farm by the dam. We stopped to have Salmon Pie, Salmon Chowder, and then fed the fish which would one day become someone else’s lunch.

The gravel road after that was incredibly rough and it was a struggle for Anna, who kept bouncing off the rocks. It was getting very late by the time we reached the Lake Ohau Weir. The wind was starting to howl, but the fast flowy track and amazing scenery of Lake Ohau made it worthwhile. At the end of the track we were picked up by Tony, a retired farmer from Buscot Station who now runs their backpacker accommodation. He entertained us with tales of farming in this region and the challenges they faced. We watched him feed baby lamb and then cooked up pasta for tea.

DSCF6024  DSCF6038  DSCF6050  DSCF6081

Day 3

It was a drizzly morning but Tony dropped us off at Lake Ohau lodge, where we warmed up by the fire, hoping for the weather to clear. A couple of mountainbikers had decided to cancel their ride because of snow at the top of the ridge, but we had to get going regardless. Luckily it wasn’t as bad as we thought. Our ride started with a gentle 10km climb, but the drizzle had simply turned into mist. The landscape was quite different to the day before, with a light dusting of snow on the mountains. The track summit was just at the snowline. Anna copped a couple of snowballs as she arrived at the top.

The 18km descent took us to Quailburn Road.  The gravel road then takes you through farmland for another 35km…before a turn off to the ‘Clay Cliffs’.  We decided not to take the detour as it was getting late….maybe next time!  The ride finished with a short singletrack to Omarama.  Nana picked us up again and drove us back to Twizel, having completed the first four sections of the Alps to Ocean trail.

DSCF6107 DSCF6120 DSCF6121 DSCF6143