Schwalbe Ice Spiker Pro spike failure

Need 29″ studded bike tires? Not that many options out there. I’m aware of:

  • Kenda Klondike (2.1″, 400 non-sharpened spikes, 1464g)
  • Nokian Extreme (2.1″, 294 sharpened spikes, 990g)
  • Schwalbe Ice Spiker Pro (2.25″, 402 sharpened spikes, 1170g wired / 890g folding)

2 years ago I wanted my winter tires to be wider and was ready to pay for the higher-end lighter option, so I bought the folding Schwalbes.

They hold fantastically on ice and pull fantastically in snow or slush. One serious disappointment was that the scale showed 1040g, or 15% over the specified weight.

Schwalbe studs losing pins

Now the second one. In just two winters, nearly all spikes from the central row of the rear tire have lost their hardened tips. The soft (probably aluminium) base squeezed down and became nearly flat, hidden inside the rubber knob. Some of the (former) spikes are pictured. It is relatively easy to replace the spikes, but I have a feeling that the rubber base is now weakened and the replacement drops out quickly.

The central row is probably not critical; two adjacent rows are in contact with the ground, and have lost just a few spikes. One must note that Kenda and Nokian just do not have that central studded row.

Collapsed rim

I managed to crash on a bike during a group ride (no one at fault besides myself). I could not reconstruct, what exactly happened: looks like my front wheel got suddenly turned aside and collapsed. The guy riding behind me told that my foot somehow mangled with the wheel, but I cannot understand how that could take place. Fortunately, the speed at that moment was very low, so the only damage I suffered is torn clothes and the pictured front wheel.

collapsedRim-1
collapsedRim-2
collapsedRim-0

Just recently I had to replace the rear wheel from this set because the rim did not withstand the spoke tension. That time, it was obviously the product’s inability to hold the applied load, which is a tradeoff for the ultralight weight. Now, with the front wheel, I do not have an indication that the ultralightness is at fault, as I do not exactly know what had happened.

Ultralight rim failure

I had to replace a rear wheel before leaving for a longer group ride:
crack-1
Drive-side spokes were tightened to 100Kg, which was just barely enough for non-drive side not to go slack.
crack-2
That was the most prominant crack, but not the only one – in fact, all drive-side sockets have developed smaller or bigger slits:
crack-4
This was an ultralight-class wheel with 24 spokes and under 400g rim. Weight-limited to 80kg, which I fit in, but without any reserve, has served me for some 10K kilometers. So I have decided not to send any claims to a vendor, but also not save on spoke number the next time – or use more meaningful 16/8 spokes.

754g, that is with stick-on rim tape.

754g, that is with stick-on rim tape.

Update: In just two weeks the pair front wheel collapsed in a small crash, so this ultralight wheelset does not serve me any more.

OpenStreetMap, no dead ends!

I enjoy wandering around the countryside – also without planned route. Would be nice to mark roads, which are less interesting than others? For example, all dead-ends, and in general cut edges of the road graph.

Good that we have OpenStreetMap with open data and tools. I have created software to pre-render a given region (not too large one) with all cut edges marked. This is how it looks like, marking with thick blue dashed line:

Marked dead ends on OSM

Painted dead ends on OpenStreetMap

Storing and providing OpenStreetMap tiles requires a lot of disk space and bandwidth, so for now I only rendered small regions as a proof-of-concept. Welcome to peep at the maps!

SRAM ESP ~ Shimano Dyna-Sys

I have got a report that these two types of rear deraileurs have the same mechanical advantage:

  • Shimano Dyna-Sys (which are marketed only as “10-speed”)
  • SRAM E.S.P (which are marketed only as “9-speed”

Sram ESP and Shimano Dyna-Sys rear derailleurs have same mechanical advantage

Both take 35mm of cable to go over the whole cassette. Picture shows SRAM X.9 and Shimano XT, but any other derailleurs of the mentioned types would be interchangeable.

This means that either one can be replaced with another (provided that it can handle your biggest cog). I have not verified this myself. Remember that “SRAM 10-speed” deraileurs have different mechanical advantage, as do “Shimano 9-speed” ones, and there are no other pairs which are not designed for each other but work.

Maybe not a really useful finding in practice, but certainly an interesting one.

Polar Norway 2010, short cyclo-hiking or carry-cycling

In August 2010, I made a fast 4-day cycling and bike-carrying trip over northeast Norway. Varanger peninsula, one of real “ends of the world”, is almost encircled by roads, the gap is “just” some 20 km. Here is the map, with the blue track following the roads where I was riding on my bike, and the red track showing the part where the bike was riding on me:

Route map

Report with photos here. I’m wondering how is it possible that I’ve been to that region already three times and I’m ready to select it for my vacation trip once again.

Me on a plateau

Bicycle in Finnish Pendolino train

In Finland, most trains allow transportation of bicycles, but the fastest “Pendolino” trains do not.

Recently I traveled with my MTB, and Pendolino was the only feasible option (it was the first morning train, the next one arrived already too late). The only way was to partially disassemble and pack the bike so that it becomes normal luggage.

Packed bike in the room


Continue reading

Shimano Nexus-7: how it works, how many teeth the gears have

Previously, I have tried to find “theoretically” the tooth counts of the Nexus-7 internal gear hub. Some nice numbers were obtained, but there were some suspects (you may think yourself what can be wrong with the numbers given in the link). Soon after, I disassembled the real hub and counted the teeth of all rings. Here are the real numbers. Continue reading

Nexus-7 gear tooth counts and exact transmission ratios – wrong version

ShimanoNexus7 Vendors of internal gear bicycle hubs naturally give the transmission ratios of own products. But I was always curious how exactly these ratios are obtained, i.e. which planet gears are engaged in which combination and how many teeth each gear has. This information was surprisingly hard to find – in fact, the only vendor who discloses this is Rohloff! It is certainly possible to just disassemble the hub, but, you know, sitting half-day at the computer screen is more attractive nowadays 🙂 I have Nexus-7 hub on one of my bikes, and I have “reverse engineered” the exact tooth counts. Continue reading

Heavy-duty self-made mudflap

DIY heavy-duty bicycle mudflap
Bicycle mudguards are frequently made shorter than they should have been. I was not able to find a front mudguard which would protect front chainrings from water jets pouring from the front wheel. So I made my own from a 2mm thick rubber sheet. It is heavy and non-aerodynamic. It is heavy-duty! It makes difference when riding in the rain. It is tested. Highly recommended for bike commuters.

Trip report from Indian Himalayas – 2008

Lahaul valley
I’ve started writing about my last year bike trip in the Indian Himalayas. Before I had not forced myself to more than one blog post and an unsorted pile of photos. Now I’ve started with a short illustrated text about practical issues, answering questions which I had at the planning stage:

Cycling in Himachal Pradesh: practical issues

My next plan is to publish the daybook with facts and impressions. Stay tuned.

Summer has arrived: family tandem ride

We’ve done a great sunny full-day ride on our tandem with a kidback plus two other bikes. The target was Vanhankaupungin koski (stream and a waterfall), one of the city attractions we had not visited before.

This made 56 km and 10 hours door-to-door. I think it was the first day of the year when it was possible to cycle in shorts – not morning and evening though.
Map of the ride: Continue reading

Cycling in Himachal Pradesh, India

It has been a month since I have returned from solo cycling trip in Indian Himalayas.

Impressions clearly overloaded my brain. This was first time I’ve been to Real Mountains – the highest pass, Kunzum, was at 4500m. And this was my first time I’ve been to a non-Western country (not counting my home Russia, which I’d put “on the border”).

The route was easy: start at Shimla, and follow the National Highway 22 (with some variations in the beginning) until Manali. Oh the highway… Never have seen anything like this before.

Numbers, mostly of interest to cyclists only:

  • 9 ride days
  • 750km covered
  • Total altitude gain is still not counted, although three biggest gains were 1600, 1300 and 1000 meters

What else:

  • Was caught in a snowfall in Lossar, 4000m:
  • In the plains (Chandigarh), the temperature was in +30 range
  • On the National Highway 22, passed landslides three times. Two of them, the bike could just ride through, like this one:

    once had to wait until it’s cleaned (I waited just half an hour, but others were there from the morning to the evening):

  • Stayed in the tent two times, in hotels and various “rooms” 11 times.

In fact the impressions of India as a country overweigh the “mountain-cycling” impressions. It deserves much more than one blog post – even much more than one book. All my perception of the surrounding world is now a little bit different than it was before. Probably such thing is called “cultural shock”. I’m so happy that this happened; now I see how terribly narrow view I previously had.

Of the real India, I have seen only Chandigarh, which is described in all guides as most comfortable city in the country. Still it is, of course, Indian city (just like my home Saint Petersburg is the most European of the Russian cities, but still fully Russian).

I’m feeling own deficiency of not being a good writer to describe my thoughts about these two weeks. So far I have produced a technical report, with details for cyclists such as what tires to put on your bike and how much food to carry.

All pictures (unprocessed) piled here.

2000 km from the season start

Today evening I was catching last weekend of the school vacation. Starting from tomorrow, my time limits for the outdoor activities again become much more strict. And there was a great chance to use it: in a company of Antero and Matti (thanks for calling me in!), we made 100km at average speed a bit over 30 km/h.


View Larger Map

Now I have 2000km on my roadbike’s computer during this season. Quite an achievement for me, taking into account that I was not cycling during 3 weeks when we went out for family trips, and that I do most of my everyday commuting on the other bicycle. Now intensive collection of kilometers slows down; I have a positive feeling that the time available to collect them was used at full extent.