As I alluded to on my home page, this Surly Disc Trucker is now my new touring bike.
What happened to the previous touring bike you may ask? Well, I felt that the K2 touring bike that I cobbled together for a touring bike was showing its age and with it being an aluminium frame, I was wondering how many more trouble free years it would last without showing any weld fatigue etc. It had been knocked about quite a bit over the years travelling on several flights abroad plus some other minor mishaps. So that’s my reasoning, but to be brutally honest, I just wanted a new bike!!!
So time to switch to a little less stiff steel frame for a change as both my previous touring bikes were aluminium. I didn’t want to buy a complete Disc Trucker as I preferred to customise my component choices and beside the K2 had some good components on it which I stripped off and kept for the the new build-up of the frame and fork that I bought new. One big advantage in just buying a frame and fork is that I get to decide how high I would like my steerer to be cut off instead it being cut off to the bike manufacturer’s/builder’s standard; for touring, I prefer my handlebar higher so I didn’t shorten the steerer at all on this build. The K2 frame and fork were donated to a bicycle recycler.
Surly’s Long Haul Trucker (LHT) bikes have been around for awhile and are a well proven touring bike ridden by many adventurers to near and far away destinations. The disc version evolved around a similar frame geometry as the LHT but this has changed for 2020 with a new model that has the geometry modified somewhat plus some other changes. You can read about the full revamp of the Surly Disc Trucker (SDT) on the Surly website. I purchased a 2019 frame and fork without knowledge of the newer model coming out the following year, but ultimately I’m not disappointed with my 2019 rendition.
Handlebar, stem racks, Brooks saddle, crank, chainrings, derailleurs, pedals, fenders, bottle racks etc. from the K2 were salvaged and reused on the SDT. Reusing the drivetrain from the K2 was an easy choice to accomplish the same gearing that I prefer for loaded touring (gearing chart below). Yes, I still use an eight speed cassette but find no need to change from easy to find and inexpensive drivetrain components. I had to build new wheels with the appropriate hubs to accommodate the, new to me, disc brake rotors. What did I have to buy to complete the build? Well I could have salvaged the rims from the previous non-disc wheels, but it made more sense to sell those and recoup some of the cost of the new wheel components. So, new cassette, rims, spokes, hubs (I prefer to build my own wheels), hydraulic disc brake levers, rotors, calipers and hoses. I tried to use my Paul’s Thumbie shifters but with the new brake levers and my butterfly handlebar setup it was just not possible which brought a little more expense for some new thumb-shifters. A new seat post was also required due the different seat tube diameter of the SDT compared to the K2. And that’s about it I believe.
So you may question my choice of hydraulic disc brakes as opposed to mechanical (cable actuated) disc brake on a touring bike? If I was still riding long distance, multi-week tours, I probably would have gone with the cable actuated mechanical disc brakes (easier to repair in the field), but I seem to stay closer to home venues nowadays so hence my choice for the superior braking performance of a hydraulic setup.
As my legs get older the granny gears needed to get lower! And I played with the gearing a few times on the K2 to accommodate that fact. Below is the gearing configuration that is similar to what the K2 was – I say “similar” because using the Shimano 11-32 cassette gives a better ratio between gears as opposed to a SRAM 11-32 cassette that I had on the K2. Notice that I have two very low gears – granny and “super granny!” The 16.1″ low is about as slow as I can go and keep the bike in a straight-ish line without falling over 🙂
The gearing calculations below are in “gear inches” which is basically how far the bike wheel will travel in one revolution of the pedal crank.
- Frame – Surly Disc Trucker 4130 CroMoly steel.
Main triangle double-butted. TIG-welded
- Front Derailleur – Shimano XT
- Rear Derailleur – Shimano LX
- Pedals – MKS BM-7
- Shifters – Shimano Alivio SL M410 3X8S 24S Speed
- Brakes System – Shimano Deore M6000 Hydraulic Disc Brake Groupset
- Brake Pads – Shimano JO3A Ice-Tech Resin
- Rotors – Shimano XT RT86 160 Brake Disc Rotor Ice-Tech
- Crankset – Shimano LX cranks – Chainrings 46-32-20
- Chain – KMC x8.93 8 Speed Chain
- Cassette – Shimano CS-HG51 8 Speed 11-32T
- Bottom Bracket – Shimano UN-55
- Headset – Race Face
- Rear Hub – Shimano XT M8000 Disc 36 hole
- Front Hub – Shimano XT M8000 Disc 36 hole
- Rims – Sun Rhyno Lite 36 hole
- Fork – Surly 4130 CroMoly, lugged and brazed
- Saddle – Brooks Conquest
- Tires – Schwalbe Marathon Mondial 50-559 (26 x 2.00)
- Rear Rack – Tubus Cargo