This is the Snafu Knob Job tire (26×2.35), acquired lately after doing some research and review about availability of fat tires for dual purpose usage (see previous article about tires). These tires seem to be acceptable for tarmac usage, on the other hand provide good grip and have got much better offroad capabilities than Schwalbe Fat Frank that I used previously. Also, they look quite durable and nice and were cheap due to some special offer over here. However, I have not yet done much of test riding.
Big Dummy with Snafu Knob Job tires
Snafu Knob Job tire fit at Spank Subrosa rim
Snafu Knob Job tire fit at Spank Subrosa rim
Snafu Knob Job tire at Big Dummy
BTW I may very well throttle this blog a bit within the next weeks or months since there are some motorcycling issues currently attracting my attention. But the Big Dummy stuff will be continued as soon as salt on roads will be swept away.
I will have to replace my Big Dummy tires for my 2009 trips. Up to now I used Schwalbe Fat Frank, which showed good riding comfort and low resistance, but I was not really impressed with their durability. I am currently looking for longer lasting tire alternatives. My requirements are
big fat tires with good riding comfort
hybrid tread pattern for road and light offroad usage, running easily
acceptable durability even with some load on bicycle
not too heavy if ever possible
These are some ideas for pretty wide 26″ Big Dummy allround tires:
Maxxis Hookworm (2.5″): good looking and durable, but extremely heavy, good grip on tarmac, limited offroad usage
Finally, for you fancy wheelbuilders out there I would like to point out availability of white powder coated spokes at Halo. They are selling them in many lengths, unlike those colourful atomlab spokes being sold only at some very specific lengths for atomlab hubs and rims. I have been searching for such spokes previously, so I would like to add it here.
Late addendum (2009/01/28): I finally decided to order a set of Snafu Knob Job tires, listed above. I got them fairly cheap and they look nice. In the long run I might switch over to using the new Schwalbe Marathon Extreme DD being not as heavy on the one hand, but longer lasting on the other, but these are very expensive and they are not yet available right now.
Schwalbe Fat Frank rear tire after 3000km of tarmac usage mostly, some offroad also. The brown dot is tread wear. There is no more creme coloured rubber there. To me that means, durability of those tires compares to narrow road racing tires.
The Hirschbichl is a famous little pass between Weißbach near Lofer and Ramsau/Hintersee with some steep 30% slopes at both sides. My trip went from near Saalfelden, starting yesterday at 3:00 p.m. via Berchtesgaden, Zill (another nasty 25% of slope), Hallein, the Wiestal, Faistenau to Fuschl/See, arriving at darkness and cold, 80 km altogether, exhausted.
I had some very small video camera with me and captured some sections of it. Music track is ‘Blueberry Hill’, performed by Erika Stucky on Suicidal Yodel.
I would like to refer to my previous article about tires, steering, rigid fork. The steering issues were mostly fixed by increasing tire pressure. The fork oscillation happened again when riding downhill from the Hirschbichl at some very steep section. I guess this is a matter of using rigid forks with strong brakes probably, but this is not related to the specific BD frame and fork. Will keep it in mind.
Big Dummy naked, showing fenders, tires, rear details
Basically the BD frame builds up straight forward without any concerns or caveats. Get yourself some long cables, liners and wires and start. Here are just some small issues I encountered when building up the big dummy at home. Please have a look at Surly Spew for the real important topics of it.
Disk brakes
Handle bar setup with XT disk brakes, cabling etc.
When using disk brakes, take care you can get some rear brake tubing of probably 190cm in length. Magura offers up to 250cm, Shimano does not. With my 2008 Shimano XT disk brakes I had to use replacement tubing. I had a 250cm Magura liner in my toolbox, so I cut off Maguras fixed end and installed both ends with Shimano olives and Shimano hex nuts.
At my forks IS2000 clamp, the Shimano caliper needed some more radial offset since there was not enough clearance between disk and caliper. Luckywise the caliper uses postmount standard and therefore I could insert some spacers between caliper and postmount adapter. I have no idea how this could be fixed with some IS2000 caliper.
Take care for freeloader bag! Put some protective material at the inside of the left freeloader bag, where it hits the caliper. At long downhill sections it might get too hot for the nylon material. Or better use the quite expensive Xtracycle disk mount kit pretty well pictured in this nice BD build to protect freeloader bag from hitting any hot brake parts.
Tires and fenders
Front view
Surly permits use of 2.5″ tires. With Schwalbe Fat Frank 2.35″ I realize there is enough lateral tire clearance, but it gets very tight at the rear end of the frame since this type of tire has got quite a high profile. Maybe this is the reason why it offers great riding comfort while being quite fast on the other hand.
Mud catchers: frame and fork offer several thread eyelets for different purposes. I use SKS Bluemels, ATB version. These are lightweighted adaptive mudguards made from plastics fitting most 26″ bikes. Tire width should not exceed 2.25″ according to SKS, but it fits 2.35 Fat Frank tires on 30mm wide Subrosa rims as well, as shown in picture below. There is not much clearance in between, but it works. At the left side, I cut away one of the holding stays since it collided with brake caliper. It would easily be possible to mount it above the brake caliper since there are some more eyelets, but I decided to leave those for later usage. Front guard mounting is visible in the picture to the right. Take care there are safety clips installed at the front fender stays allowing them getting ripped off from eyelets, to avoid wheel blockage in case some stuff gets in between tire and fender.
Drive train
The BD can be driven every way you like, but I prefer internal gear hubs. While Rohloff is too expensive, NuVinci is very interesting but too heavy and SRAM i9 is too heavy compared to Alfine, I chose Shimano Alfine 8 speed hub (1600g) with a 20 teeth sprocket. This hub is quite cheap, looks nice, seems to be durable and fits the frame, although the dropout slots are a bit too small for the anti torsion spacers. It could easily be used in combination with a dual crankset and front deraillieur, since a chain tensioning device is needed anyway due to vertical dropout slots.
Nevertheless, for me it works with single chainwheel and 8 gears, and I do not even need a long shifting cable since Shimanos standard length of 210mm will fit by far. I believe it is nice to have only one cable instead of 2 for Rohloff or NuVinci, just for simplicity. Removing the rear wheel is slightly more messy, on the other hand.
Although being 173cm in size, I am using short cranks of 160mm length. At the BD this is of advantage due to low ground clearance when going slopes and riding offroad and bumps. I may recommend Token bottom brackets made from carbon and steel. These are lightweighted and up to now appear to work completely silent without any cracking noises. In Germany you may get them for instance at Radplan Delta together with fine and lightweighted cranksets from TA Specialites or Sugino or many others. With a 34 teeth chainwheel I am capable of riding uphills at 15-20% and even more, strongly depending on the load, and it is still possible to pedal at speeds up to 40km/h.
Xtracycle
The Xtracycle rack is mounted losely. There is no fixed connection holding it in place. Since I do not like the lateral sloppyness of the V-racks, I wrapped some tape around its exterior tube sections before plugging them into the rear frame extension. This way the V-racks will stay in place a bit better and sloppyness is reduced. Also, as suggested by Surly Spew, use sections of thin bicycle tube covering the connection sections to avoid water, rain and dirt getting into the frame tubing where V-racks are mounted.
Nevertheless, always use some strap to connect V-racks to each other, no matter whether snap deck is mounted or not. When riding out of saddle and swinging the bike laterally your load might behave badly otherwise.
I have mounted a child seat on the snap deck. When using it, I fix it by a strong strap connecting it to the V-racks and being pulled firmly. Also I have several leather pedal straps for multiple purposes as to my needs.
Bicycle electrics
To me it sounds very reasonable to put lighting equipment on a cycle like the BD. Apart from being obligatory in several countries, there is no way around it when riding at night. Since I do not like messing around with batteries, I installed a SON dynamo hub with LED rear- and front lights and firm 2 wire cabling. Everything works without batteries. There is light even when bicycle stops. The Xtracycle V-racks are a perfect place to mount a tail light and some reflecting stuff. The headlight is mounted at the usual location at the fork.
