As cheap bastard, I’ve been thinking about reduce costs of running drivetrain. Everybody came across the situation when it’s time to replace chain and often during couple first rides new one is actually noisier, making strange clunks, and sometimes skipping. If you replacing a chain to second one when is stretched already to magical 1% is not too bad. Chain quickly will adapt to existing drivetrain, and if you’re lucky another 5000km can be done on it (depend obviously on weather and surface you riding on). Third chain is usually completely different story. Third will be noisier and there’s good chance will be skipping. If you’re lucky enough sometimes new cassette will do the job. If you aren’t, chainrings need to be changed (as well as cassette). The only good news are that you have third chain already ;-).
People been using three field crop rotation for centuries… Ok start again ;-). Don’t remember where) I came across with three chain method. Basically it’s quite simple (almost like three field crop rotation). Starting with new drivetrain and two chains in a drawer, changing them on regular basis, based on wear. You need to catch the point where wear is about 0.5% (that’s only my suggestion) and replace to #2, and again when #2 wear reaches 0.25-0.5% to #3. When third chain finally will stretch just about the same as both previous, get back to chain No1. Of course to do it properly chains need to be clearly marked. I’ve only started the whole procedure but I’m writing measured stretch* on the box, approx km made, as well as chain number and bike it belongs. (calliper reading). That will give me a rough idea when to check again and what to expect. (variation of that method is changing chains willy-nilly, every time replacing to the “shortest” one).
In terms of costs, the whole fuss at the end, might be not that efficient as I’m expecting but changing chains using that procedure is less stressful and change almost not noticeable. Comparing to “revolution” every 4-5000km with new chain “adapting” to old drivetrain is smooth and easy. So the more laborious*** method might be actually beneficial in terms of comfort, but for me that’s enough. Even without money benefits I’ll rather listen to birds singing than clunks and creeks. The thing is, after reading lots of cons/pros on Internet, opinions are almost exactly 50/50. I thought “what the heck, I’ll check it by myself, won’t cost me arm and leg” and have opinion based on experience rather than duplicating Internet bollocks.
* Measuring chain wear (stretch). That’s quite a subject. As Rule 24 stays, I’ll be describing everything in metric system (it’s not a rocket science to convert everything to inches/miles). Measuring the chain can be done using special tools but in my opinion standard vernier (or electronic) calliper will do the job equally ok, or IMHO even better. Some fancy tools like ParkTools or Rolhoff might be even more expensive than callipers. The other thing is that you might find having callipers quite handy, not only for measuring chain wear, but also they’re useful for measuring chain line, seatpost dia. etc etc…
My method: 1. Shift to big chainring and 2nd-3rd gear on cassette (you need to figure out when chain is straight = parallel to bike axis).
2. Block rear wheel and apply some pressure on pedals (don’t go crazy just press by hand).
3. Set up calliper to 130mm and place the inner jaws between the rollers (between outer plates), and stretch calliper. Like so:
The reading in my new Shimano chain CN-5701 is 132.2mm so 0.5% strech is 0.661mm to be on a safe side I can use 0.6mm but because I’m measuring wear of two rollers pushed aside** as well, I’m using 0.7mm, so wear between 0.25-0.50% is something about 132.5-132.9mm.
I’m keeping an eye on distance I’ve done on a chain and for CN-5701 0.5% stretch is after about 1200km on the clock in wet conditions (I mean WET conditions as in this example I’m using my “weather bike” and this is island but not Gran Canaria). Theoretically whole setup will last about three rotations without any problems. Then you buying extra time. Lets say if drive train will be ok after 4 changes you’ll have 12-14.000km on the clock. So it’s about two times than standard lifespan of chain-cassette. This maybe isn’t something impressive in terms of costs reduction, as well as my labour (once a 1000k I need to replace chain ***).
*** To make whole procedure easy I’d recommend using chain connectors. Good choice is SRAM PowerLock (based on internet opinions), but as I’m not able to produce wattage like Andre Greipel in my case BBB BCH-10 do the job perfectly 😉
By the way, we all know that good ride depend on lubrication. In any sense. LOL. Two day ago new oil arrived, as my old green Finish line run out. This time I’ve purchased Rolhoff oil, as got plenty good opinions across Internet. Will see…
keep them rolling
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