How to tighten the Hollowtech II (on R2000 Claris) cranks? The owner's manual on my new bike (with the new Shimano Claris, not the old one with Octalink) asks me to do this:


  After the first 20 km tighten the crankset and also tighten the pedals in the crank arms. Check if crank bolts are properly tightened. Check whether left crank arm screws are tightened firmly when bottom bracket axle is integrated with right crank arm.


I found many tutorials on the web they are about assembling the cranks, replacing them and they all include removing the cranks. But if I understand the manual, it specifically instructs me not to do that and leave such operation to a specialist:


  Important warning! No check of crank arms fastening ... may result in ... Such damaged crank arms must be replaced with new crank arms. Please contact special bike service for crank arms replacement.
Park Tool's website has quite a few "fix your bike" tutorial videos.  You may have already seen this one:

Crank Removal and Installation - Two Piece Compression Slotted (Hollowtech II, FSA)

I do wonder how many bike shop mechanics go to Park Tool's website and watch the videos for tips on how to work on obscure parts.

In this case, "how to tighten the crankset" is a necessary part of installing such a crankset.  For this video, that starts about the 4-minute mark.  In this case, all you probably need to do is get the proper Allen wrench and make sure the two clamp bolts are tight.  (And that doesn't mean King Kong tight...)

There's nothing special about doing your own bicycle maintenance - there's nothing really hard about any of it.  Even building your own wheels from parts is actually easy if you have the patience and can be done with just the proper spoke wrench (preferably a good butterfly one, as using some of those tiny spoke wrenches to build a wheel can be tough on the fingers).  In some cases, you will need special tools.  For a Hollowtech II crankset removal, you need something like a Shimano TL-FC16 Crankset Arm Tool to get the dust cover off.  (Hint - you have to loosen the two Allen bolts holding the crank arm tight to get that cover out...)