I got a good deal on a used crank and was putting chain rings on and noticed these lines that look like cracks. They line up with the typical cast marks of these cranks. Look cracked?
by yungaclvin
I got a good deal on a used crank and was putting chain rings on and noticed these lines that look like cracks. They line up with the typical cast marks of these cranks. Look cracked?
by yungaclvin
7 Comments
Damn. I thought, for the price, those would for sure be forged
Check out the current Shimano recall. Those don’t look right. A local shop should be able to help you out. You don’t need the receipt, don’t mention they’re second hand, though I don’t think with this recall it matters, better just keep that info to yourself though.
You can check if your cranks are affected by checking here
https://bike.shimano.com/en-US/information/customer-services/corrective-actions/11-speed-hollowtech-ii-crankset-recall-notice.html
Yeh those look toast. It’s hard to tell exactly from photos, but I’d be very concerned about the structural integrity of those.
https://preview.redd.it/00774zjm7yrc1.png?width=3024&format=png&auto=webp&s=21f26ca5dfcbb596033378c65059ef6ae046566c
This is mine. I don’t think you have to worry
I wouldn’t use them
Completely normal for that generation of cranks to appear this way, all of my Dura Ace/Ultegra/105 10-speed cranks have manufacturing marks on the inside. Here are some FC-7800 pictures i found in a quick google search:
https://ejrecyclery.com/cdn/shop/files/capture000042_e92cb203-688f-4182-95f9-8e163cab5c9d_600x.jpg
https://www.flickr.com/photos/23481326@N05/6088977126
https://cdn11.bigcommerce.com/s-1rmgckn/images/stencil/2280×2280/products/8757/102172/high_end_used_bike_parts_portland_1634__71443.1583284140.JPG
The curved one looks a lot like cracking to me. It’s hard to tell from photos, though. But if you’re not sure inspecting them in person, take them to a reputable bike shop for a second opinion.