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So far it’s a solo ride.

Bike of The Week: Derek's Mosaic RT-1 Disc

Derek Yarra |

A few months back I wrote a report on my trip to Louisiana to race the grueling Rouge Roubaix with team Mosaic. Back then I spoke briefly about my bike for the race but now that I’ve put over a thousand miles on it and refined the details of the build, it’s time for a full blown write up.

First, allow me to reintroduce the bike in all of its glory, my Mosaic RT-1 Disc.

Derek's RT-1D, 2015

Before getting into the build specs and all that, let me give you a little background on me as a rider that might shed light as to why this is my perfect bikeWhen I first got into racing adult sized bikes (rather than the BMX bikes I grew up racing) some friends and I put together a little team we called Ultra Doom. We listened to a lot of metal, exclusively rode and raced metal bikes, and did stupid things like taking detours from our road rides to plow through the bushwhacked single track on 23mm racing tires, or very sketchily bomb down steep, rutted out DH trails on our cross bikes. I know the industry has come up with this revolutionary new genre called “gravel grinding” but what we were doing wasn’t really that. We were mostly just doing really stupid things on bikes that we really shouldn’t have been doing them on, on days we didn’t need to be focused on any real training.

As time went on, I found myself jumping around onto different disposable, flavor of the week carbon bikes. They were all great but they always seemed a little more fragile and definitely needed to be ridden a little more gently. When the opportunity arose to have a custom Mosaic built for me, I knew that it was time to build a bike that could live up to the Ultra Doom days and really be everything I needed in a road bike.

I have grown to love and prefer the ride and handling of a pro tour style race bike. I love how race bikes feel in the corners and as you can see my preferred fit is quite agressive. With this bike, the fit and geometry nearly mirrors my previous road bike. That said, I am a mountain bike and cyclocross racer and quite rarely race on the road, so having a super light weight bike didn’t really matter to me and the ability to tackle any road or any trail took priority. With that in mind, the decision was made for the bike to fit up to 30c tires, have disc brakes, and obviously be built out of titanium.

The Shimano RX830 wheelset is the disc brake version of the C35 clincher. They are by no means light but they are tubeless ready, incredibly smooth, look cool,  and like all Shimano wheels they are totally bombproof. The bike is built with a Shimano Ultegra Di2 drive train that not only shifts flawlessly, but quite nicely matches the finish of the wheels.

I added the teal Chris King bottom bracket to add a touch of color, tucked away behind the dark gray Ultegra crankset.

Whether you are pro disc brakes or not, you have to admit that the bare seatstay bridge has a refreshingly clean look.

The Shimano Freeza rotors are a true work of art and match the craftsmanship of Mosaic's welding prowess. XTR skewers are definitely not the lightest but they provide some of the most secure clamping power and tie in well with the rest of the Shimano kit. Disc brakes are a hot topic these days. I will be the first to admit that they are not for everyone or every bike, but I absolutely love them. I could go deep in explaining why but I'll save that for a later post.

Mosaic has one of the cleanest executions of internally routed brake lines.

The Deda Zero/100 handlebar in 44cm offers a ton of real estate on the tops while having a very nice bend to them. Not too shallow, not too deep, and a very comfortable shape to the bend. The Shimano R785 levers prove that the future is here. Not a single cable on this bike, only hydraulic brake lines and e-tube shift wires.

I have ridden and trusted Thomson posts forever and it was an easy choice to pair with the hand made in America frame. Similarly, I've been riding San Marco Aspide saddles for a few years now and I've yet to have a complaint. It also happens to be one of the lightest saddles out there.

All in, I could not be happier with this machine! I wanted a bike that I could do anything on and never have to worry about. This Mosaic RT-1 is exactly just that. It has the spirit and feel of a full on race bike but the brawn to ride anywhere you point it. Call it a grave bike, call it an adventure bike, I don't really care. For me, this is just what I need from a road bike.

Here's a break down of the whole build spec for your internet bike nerdery:

  • Frame: Mosaic RT-1 Disc
  • Drive Train: Ultegra Di2 with hydro disco brakes
  • Handle bars: Deda Zero/100 44cm
  • Stem: Custom AC painted Deda Zero 100
  • Saddle: Selle San Marco Aspide
  • Seat Post: Thomson Elite zero offset
  • Wheels: Shimano RX 830
  • Tires: right now, Conti GP 4 Seasons
  • Tape: Fizik superlight
  • Pedals: Speedplay Zero stainless
  • Extras: King Cage Ti cages, V2 Barfly. Chris King BB and headset
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