Overhauling a Dura-Ace 10 Crankset


For my gear-head cycling friends out there, a bit of bike maintenance porn. Tonight I faced a daunting task I have avoided for well over a year now. That is, dissembling the frankenstein-like Dura-Ace 10 crankset on my bike and replacing the bottom bracket. (Yes, I’m a geek but you knew that.) So, I admit it. I was intimidated by the Dura-Ace 10 crankset. Heck, I’ve avoided looking directly at it for almost two years let alone take a wrench it. After all, everything about it is new and unconventional — from the asymmetrical oversized parts, to the monolithic left crankarm that bolts onto the one-piece axle and right crankarm, to the specialized tools required to remove the crank cap and bottom bracket cups.

Shimano Dura-Ace 10 crank schematic

With parts from Performance bike shop and the Shimano schematic inhand I was ready to face the crank. The disassembly turned out to be more straightforward than I expected but it definitely took a bit of force to remove the bearing cups from the frameset. Nothing the tap of a hammer at the end of the bearing wrench couldn’t solve. The main axle and right crankarm assembly wasn’t quick to budge either but a small sideways tap with a hammer and wood block solved that as well. In the end, it was an unexpectedly easy job — the mark of a well engineered system. If you own Dura-Ave 10 and have been avoiding this task like I have, I encourage you to check out the PDF manual from Shimano and grab the necessary tools from Performance (under $20 total) and have at it.

As a side note, the only slightly concerning discovery is that my crankset is missing the “stopper plate” shown in the Shimano diagram. Hmmm, should I be concerned? The plate appears to only hold the assembly together in the event that both the left crankarm and end cap come loose — a highly unlikely scenario it seems. Besides, it took quite a love tap to free the axle from the bike in the complete absence of the left crankarm and end cap. Guess I’ll look for a replacement but won’t worry about it much in the meantime. Happy riding.