Bike – The bike I used for most of the trip was an MSG custom titanium frame. Sadly this broke as I was making my way across Poland towards Berlin. I purchased a Cube Tonopah trekking bicycle to get me the rest of the way home. The MSG broke at the joint between the seat tube and the top tube. It wasn’t the weld, the weld was good. The frame just didn’t have the rigidity to resist the bending moment between saddle and top tube, so it suffered metal fatigue. I didn’t need, or really want the stand over clearance the frame provided. If the frame had had a less steeply sloping top tube, it would have been stiffer and probably lasted forever as intended. The frame had 4 sets of bottle mounts. The 4th set was on the underside of the top tube. This was intended for mounting the pump and turned out to be ideal as it kept it well away from mud and spray. Although the bike was designed to accommodate suspension forks, I used rigid as suss forks would require maintenance over the distance covered. I ran a 40 tooth front sprocket, 19 tooth rear with Rohloff hub and 47-622 Marathon Mondial tyres. This gear range proved ideal. I didn’t use the lowest gear much, but it did get me up onto the Pamirs on a badly churned up road. I carried a spare tyre but they lasted throughout. I did use the spare but this was only for convenience when a staple had embedded itself in the tyre and I couldn’t get the nose of my pliers on it, so for speed I used the spare. In the evening I managed to push the staple out far enough using my penknife to get a purchase on it with the pliers.
Fatigue Crack through top tube/seat tube joint. Just hanging on by a thread at this point.
My Shimano XTR quick release pedals did not show any signs of extreme wear before I departed. There was no discernible end play between the pedal body and spindle. I had never heard of pedals failing catastrophically. However, that is exactly what happened in Tajikistan. The pedals had started to show some play, but very quickly the bearing completely failed and the pedal just slid off the spindle. Because the spindle is tapered it was not possible just to pack with grease. Every time pressure was put on the pedal it just shot off sideways.
Wheels - I didn't have much luck with wheels. I damaged the rear twice. Luckily both times I was able to make it to the only two bike shops along the route through Asia with the parts and equipment necessary to re-lace a wheel. I used DT Swiss M520 rims 32 hole. This was paired with a Rohloff hub gear at the rear and a SON dyno hub at the front. In Myanmar I cracked the flange of the Rohloff hub and had to divert to Bangkok for a replacement hub body. At this time I added reinforcing rings usually used on tandems. The second breakage was when I cracked the rim around many of the spoke holes when I was forced off the road in Turkey and the rear wheel dropped into a storm drain grate. Fortunately the cracked wheel lasted until I could get a replacement rim in Istanbul. I now use Ryde Andra 30 rims.
Cracked Rohloff Hub. 1 of a pair
1 of many cracked spoke holes
Shiny new hub body with tandem rings for extra strength
My own personal opinion when looking at the crack was that the difference in stiffness around the flange caused by the bolt hole castings acts as a stress riser making these points more likely to crack & separating the flange from these would reduce this tendency.
Brakes – Hydraulic disc brakes are not usually recommended for expedition use. However, my bike only had disc mounts. The tight clearances to the rear rack would have prevented a mechanical disc from fitting. I had been running Hope Tech 3 X2 for some while. I stuck with these for several reasons:- The braided hoses were robust, they use the same DOT3 or 4 brake fluid as cars which is widely available, they have a proper reservoir so you can bleed them without a special bleed kit. All that is needed for brake bleeding is a short length of hose to go on the bleed nipple and suitably sized spanner. I used sintered pads for longevity. 203 mm front and 160 mm rear discs gave ample stopping power. The smoothness of the discs were much appreciated on a couple of wet days in the mountains of Vietnam when the concrete road surface was like a skating rink. The brakes worked without fault throughout the trip so no bleeding was required.
Rack – I used a Tubus Cargo Evo rear rack as the shaped lower fitting just about gave clearance over the rear disk brake calliper without requiring any additional spaces. The addition of spacers would have weakened the joint between rack and frame. The bike frame has M5 rack eyes. As I expected the trip to be very ruff in places I replaced the standard Stainless steel allen headed bolts used for the lower rack fixing with High Tensile Steel (12.9 BZP) which have much better mechanical properties than stainless. Westfield Fasteners ( www.westfieldfasteners.co.uk) have an excellent range of fixings available in small quantities and provide a technical page on material properties. A small mod was necessary to the Disc Brake mount to accommodate the rack. The lower chunky Allen head bolt that fixes the ISO to post mount adaptor to the frame was replaced with a cheese-headed bolt so that it did not foul the rack leg.
Front Rack - For this I used a Tubus Big Apple that gave no trouble. As with the rear high tensile steel fasteners were used as a precaution for the main weight bearing fixings. Dynamo, Lights and Phone Charging - My bike is fitted with a SON28 dyno hub in the front wheel. I used this with a Edelux LED front and rear lamps. This came in handy with the various tunnels encountered along the route and the few days I rolled into town rather late. It also meant there was no worry about keeping batteries charged. The light was adequate for night time use on unlit roads. I did struggle sometimes in unlit tunnels when going from very bright sun to full darkness with no time for my eyes to adjust. The dyno-hub worked reliably throughout the trip. During the trip the hub has been subjected to extreme ruff roads, forded a few streams and been out in torrential monsoon rains. There was no discernible play in the bearings by the end of the trip. I soldered a connector into the dynamo leads up at handlebar level. This allowed me to swap the dyno-hub between lights and a Sine Wave, Revolution, USB converter. This allowed me to charge my phone in remote areas and also stop the battery discharging very quickly when using the phone as a sat-nav. I found that the Sine Wave converter was able to charge the phone to 75% capacity quite quickly but seemed to slow after this. The converter is about the size of a matchbox and was cable tied to the underside of my stem. It survived extreme heat and wet with no reliability problems to report. I cut the USB plug off an old cable and plugged this into the USB socket to keep it clean when the phone was not plugged in.
Brooks Saddle. The tension thread broke. This is the repair with an M6 bolt and two two nuts. The second is just out of sight, pressing against the silver nose piece of the saddle to push it out in tensions.