When a chainring or a sprocket is worn out, it is often possible to give it a second life. Sometimes even a third one.
Skipping of a new chain is caused by very small deformations of the sprockets. Normally they are not even clearly seen to the eye, but easily felt when you drag a sharp object along the work surface of the tooth. There is a bump; that bump is what catches the chain higher on the teeth and leads to skipping. With a dremel tool, filing that bump away takes one second (or maybe 2 seconds on a steel sprocket).
It does not even have to be removed from the bike!
A chainring is always easy to file. For cassettes, there is one case when filing is not possible: the cassette is not disassemblable (fully CNC’d, or with sprockets on the spider) and the tooth difference from the weared out sprocket to the smaller one is less than 3 teeth.
Neither chainrings nor the cassette has to be even removed from the bike for this procedure. Time spent for one pass is 1-3 minutes – about the same, or even less, than replacing the old component.
I do not feel good discarding a 10-speed cassette at the moment when its one most used sprocket skips, and 6 are almost intact. Even while cycling loads the environment much less than most other transportation means, I’m looking for ways to not impact when unnecessary. Buying two times less cassettes+chainrings makes me think that I have left a bit more of the Earth to future generations.
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.
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.
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.
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.
I had to replace a rear wheel before leaving for a longer group ride:
Drive-side spokes were tightened to 100Kg, which was just barely enough for non-drive side not to go slack.
That was the most prominant crack, but not the only one – in fact, all drive-side sockets have developed smaller or bigger slits:
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.
Update: In just two weeks the pair front wheel collapsed in a small crash, so this ultralight wheelset does not serve me any more.
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:
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!
I think I managed to give a full answer to question “Will shifter A and derailer B work with cassette C”. Or almost full. See the screenshot of the table below. If the meaning of these numbers is not self-evident, read explanations on the permanent page. Enjoy!
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”
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.
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:
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.
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
This is my DIY ultralight water bag. The bag itself, without the bladder, weighs 20 grams.
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
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
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.
Living in Helsinki region, looking for a company for evening sporty road rides? Come to Vantaankoski (the home mark on the map below) on Tuesdays and Thursdays by 18:00.
What to expect there? Continue reading
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.
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
Here is a map of my 8 March ride with IK-32 club.
View Larger Map
Are you sometimes getting a thought that the life feels a bit too routine? That you’ve done nothing really crazy for a long time?
Even if so, the good news is that there is always an escape from such dead end! That is, unicycling!
The winter – meaning, snow and ice – is not yet coming to our region, but I somehow feel that the roadbike season is over. With this thought in mind, I rebuilt my road (or cross) bike with flat bars.
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
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.