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I bought my first used Roadbike a few months ago, after some intensive riding the shaft was displaced a few mms to the left leaving the right side with less tooth-length which subsequently lead to the wear out of the teeth on both the shaft and the crank arm. Long story short, I need a new crankset.

I have a 2009 Stevens Cityflight, which has the FC-S500. This crankset is very hard to find online. I am considering some other choices, the question is : are cranksets standardized so that any set is mountable on any bike, at least when it's from the same manufacturer? If the length of the shafts, and diameters of bearings do vary where can I find the compatibility

  • Thank You guys for the immensly helpful answers , the crankset is actually worn with the confirmation of my local bike-shop. From an engineering point of view the teeth of the crank should be conceived as wear parts to keep the maintainance costs at a low. unfortunately both of components are worn as it is clear how the teeth depth decreases gradually over the length of the part. now i am in Berlin germany an i just checked a few online dealers. I found an FC-S501 crankset with the buttom brackets , eventhough im not really sure if the bearings need to be replaced as well – Bashir Maqboul Mar 27 '18 at 18:30
  • The element which is carries the torsional moment (spindle) is worn . as a mechanical engineering STUDENT, i am looking for a relatively affordable option. i found a complete crankset for alsmost 35 dollars with the corresponding buttom bracket and is a Hollowtech II but it has less than 42 teeth which would risk damaging the plantery gear at the back. i might also need another chain then. i think the best option would be to get the almost similiar set of the s501, right? I thank you guys again for your answers, i had no orientation before i read them – Bashir Maqboul Mar 27 '18 at 18:37
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First, you should be sure that the crankset is actually worn -- cranksets last a long time, and some teeth will look like they are worn (but they aren't) due to aiding shifting.

The bearings aren't in the crankset itself -- they're in the bottom bracket, which is pressed/threaded into the frame. In your case, your bike has a Hollowtech II bottom bracket, and you can use Hollowtech II compatible cranksets (or change the bottom bracket type, and use some other crankset).

When choosing the crankset, you do have to have bottom bracket compatibility, crank lengths, and if the crank clears everything on your frame when installed -- for example, most mountain bikes will have interference if you stick a 50 tooth crankset on them because the geometry of the bike is not setup to take this.

I'd suggest just going to a local bike shop to make sure you do need a new crankset, and chances are they'll have some Hollowtech II crankset that will fit your bike anyway, if needed.


Another reading of your post suggests that the splines on the bottom bracket (thing the crankset goes onto; contains the spindle which the crank arms rotate about) may be worn (is this what you mean by shaft?). In this case, you'll need a new bottom bracket and crankset. I'd leave this work to a shop if you don't want to buy the tools (bottom bracket tool, big wrench, crank puller, etc.).

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Cranks need to match the bottom bracket bearing type. Different bottom bracket types have different spindle lengths and diameters.

The Affine FC-S500 crank is designed to work with a Shimano Hollowtech II external bearing bottom bracket in a threaded 68mm wide frame shell (known as 'English' or 'BSA'). You can directly replace the crank with any that is compatible with that bottom bracket bearing and shell width.

Unfortunately this does not leave you many choices as you need a Shimano 42 tooth single chainring crank. I believe the FC-S500 is Shimano's only offering that matches. An alternative is to replace the both the crank and the bottom bracket bearing. There are many crank/bearing combinations compatible with a 68mm threaded shell.

Replacement Affine cranks are readily available in my location (US). When you say 'This crankset is very hard to find online' I assume you mean on sites that offer it for sale in your location.

You might want to check that the spindle is really damaged. It is steel and the crank is softer aluminum alloy. If the crank was slipping off the spindle the majority of the damage would have been on the crank. You may be able to just replace the left crank arm. Also, if you do replace the crank you will be able to re-use the chainring, so you do not have to find a replacement crank with a 42 tooth ring.

Reiterating a point from Batman's answer: it's probably best to let a bike repair shop replace the crank and/or bottom bracket as special tools are needed, and a torque wrench should be used to avoid the crank slipping off the spindle again.

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