Crank It Up

Something startling appeared in my Facebook news feed yesterday (9/21):

Shimano recalls 760,000 Hollowtech road cranks after receiving 4,500 incident reports.

Shimano says 760,000 11-speed Hollowtech road cranksets will need to be inspected for signs of delamination. The affected cranks — Dura-Ace and Ultegra models manufactured prior to July 2019 — can separate and break; the company has received reports of 4,519 incidents of cranksets separating, and six reported injuries, including bone fractures, joint displacement and lacerations.

There are 4,519 reported crank failures, and there could be more. It is kind of remarkable that there are only 6 reported injuries. If the crank on the Bianchi above failed like that while someone was pedaling they could really get hurt.

There are a large number of these cranks on bikes ridden by Stockton Bike Club members. Ultegra components have a reputation for delivering quality at a bargain price. Comparing Ultegra to its higher cost big brother group set Dura Ace, there is very little weight or performance difference but the DA will set you back more than twice as much cash. But the recall affects both models…

Including mine. I have a Dura Ace crank on my Sampson titanium bike, and it is one of the problem parts. So I called Robbie’s Bike Shop in Stockton to see if they knew anything about the recall. They sure did; the shop is an authorized Shimano Dealer and they had already performed 3 inspections even though the recall was only announced that same day.

I dropped the Sampson off at the shop, and they said they would get to it Friday and I could pick it up that afternoon. If it passes inspection Shimano says it is safe to ride. If not the crank will have to be replaced.

Before I took the bike in I did my own inspection. I looked carefully for any signs of cracking. I didn’t see any. But the crank is black, and my aging eyes don’t see perfectly up close even with glasses. I watched a video, and the mechanic said one test is to tap the crank with the butt end of a plastic screwdriver and listen to whether it sounds solid or hollow. Even though the crank model name is ‘Hollowtech’ , a solid sound is good, and a hollow sound is bad. Mine sounds solid to me.

Another test of whether the crank is a problem is whether it is making a creaking noise when you pedal. Usually noises from that part of the bike involve the bottom bracket, but apparently a delaminating crank might be the culprit. For what its worth, my crank is silent.

I learned on line that the local shops who perform the inspections are going to be compensated by Shimano. The inspection is free for the bike owner, so if you have one of those cranks support your LBS and take it in. They will get paid.

I’m expecting the Sampson to get a passing grade and be back in my garage in time for the Sunday Club Ride. But if not I’ve got two other bikes I can use. N+1…