I replaced my 53-39 chainrings with some 52-36 chainrings,
despite my recently acquired knee fitness, simply because my 53-39 set were worn and the chain was dropping off the bigger ring and the 52-36 were being offered new at a reduced price.
Chain drop from the bigger ring is usually the way that I judge that a chain is worn and the chain I am using is getting old but having changed to a brand new ring it is clear that chain drop is a function of chain and chainring wear. Chainrings at 50-65 USD are more expensive than the chains at 15-30 USD that I use but all the same, I am going to pay attention to chainring wear in future. The chainrings are from the newer Shimano R7000 series with different profile to the R5800 series crank arms and spider on my bike, which does not look pretty, but it does not seem to make any difference to the function. I usually use 53-39. I can't tell the difference between 53 and 52 but the smaller 36 tooth smaller ring allows for a perceptibly larger instant down change when turning to go up hills. The old chain no longer slips down from the top ring at all. I need to make it a link shorter.
New 52-36 Chainring by
Timothy Takemoto, on Flickr
I used
my new torque wrench purchased from China, as usual, to tighten the chainring bolts to about 14Nm.
I used the
new aluminium crank caps, mentioned in the last post, with 10mm hexagonal holes to tighten them up. I don't have my 10mm Allen Key with me at the moment so I stuff one side of a pair of pliers in the hole to tighten them up but even so I could get more torque than the horrible Hollowtech thumb wheel.
I also changed the brake cover on my old Felt to
some more colourful new ones from China. They don't quite fit 5700 series but they are a quarter of the price, so I will put up with it.
My new colourful brake cover from China