Shimano Crankset Recall

[charliedid]

I realize and agree that they don't look "perfect" and some look better than others but maybe, just maybe it's a requirement of the clamshell design and interface to have a measured gap. If it did look perfect would they be prone to creaking?

I've always wondered.

Originally Posted by Ttx1

Slight thread drift, but how does this product even make it to production?




All of these cranks have poor visual alignment between the spider and the rings. If this was a car, the body panel alignment would be unacceptable for any but the cheapest / lowest quality brands.

And yet, this is what Shimano delivers - and a majority of people accept - as the "best" and "state of the art" for Ultegra and Dura Ace.

No recent generation of these cranks has truly good alignment in the spider - ring interface. These look like mis-matched parts, or cheap knock offs.

Even if the bonding process was perfect from the start, the aesthetic result remains quite poor. These are not inexpensive parts - and they are positioned as category leading in performance.

And yet, I don't think I've ever a read review that suggests "part alignment could be better" or anything critical whatsoever from cycling media.

I'm harping on this here, because the design strategy of these products is all about aesthetics - bonding a fairing/cosmetic clamshell to the primary structural component. And yet, this largely cosmetic enclosure not only has super poor visual part alignment... but the design is defective, too.

In case my point isn't clear - look closely at the point where the spider meets the ring and note how the parts don't perfectly align. This is apparent on all recent Ultegra and DA cranksets - not just the one shown here - and it's 100% completely avoidable with attention to design and tolerances. In fact, that's what industrial designers do for a living - create part geometries for manufacturing that look good and function well.

How did this even make it to production?

[skouri1]

I have a 12 speed shimano crankset and I think it looks great.
I get what you are saying, but I also think the ultegra crankset is a very nice component and I am not going to ever think about it once installed or when looking at bike from 5 ft away.
They bolstered the crank and added some weight to it to ensure it wouldnt fail, thats the important part.

OH, also, the photo has 11 speed rings >> 12 speed crank. hence the slight mismatch.
Shimano is trying to ensure the crankset will shift correctly with an 11 speed group. Spacing is different on 12 speed rings.

Update:, going to try to return the Ebay SRM. Seller should really have done their homework and not sold a recalled crank on ebay. was not clear from photos. there are other odd problems with the preload adjuster as well. and the actual SRM unit rubs on the BB (which I now see, was obviously happening to them as well). Weird!

[dr_unix]

Originally Posted by charliedid

I All of these cranks have poor visual alignment between the spider and the rings. If this was a car, the body panel alignment would be unacceptable for any but the cheapest / lowest quality brands.

Indeed! I can't believe Shimano can't quickly design shape matching 11-speed rings and get them manufactured by now. It took Shimano so many years to finally do this - they had plenty of time I'm sure between when they finally decided to do something about this issue and the time they finally went public.

[dr_unix]

Originally Posted by skouri1

Shimano is trying to ensure the crankset will shift correctly with an 11 speed group. Spacing is different on 12 speed rings.

Does anyone know what the actual spacing difference is? Is using a native 12-speed R8100 crank really that bad of an experience on an otherwise fully 11-speed bike?

[openwheelracing]

Are they the same 11 speed rings as R8000 and R9100 with special adapters?

Or are they special made rings?

What about future replacement?

[batman1425]

Originally Posted by Mikej

Maybe they wind tunneled them and the offset showed a 3 watt loss? 😂

More likely a slap dash tooling job to spit out a ring that will match the new crank design well enough and preserve 11s spacing, shift ramps, etc. in a hurry and get cranks in peoples hands that will work with their drivetrains.

Given the magnitude of the recall, I would hope they would institute running updates to them.

[oldpotatoe]

Originally Posted by Ttx1

Slight thread drift, but how does this product even make it to production?
How did this even make it to production?

Really? Rhetorical question..yer talking about shimano, after all..

shimano has been doing 'head scratchers' for decades..Like DA pulleys and headset stack heights and lack of compatibility even w/i the same groups, like XT....BIG company that is really interested in the bottom line..

[Jeff N.]

I have not had a bit of trouble, luckily, with any of my Shimano cranksets, Dura Ace or Ultegra, after many thousands of miles.

[Kyle h]

Originally Posted by Ttx1

All of these cranks have poor visual alignment between the spider and the rings. If this was a car, the body panel alignment would be unacceptable for any but the cheapest / lowest quality brands.

Teslas sales number are a direct contradiction to this opinion.

[Ttx1]

Originally Posted by charliedid

I realize and agree that they don't look "perfect" and some look better than others but maybe, just maybe it's a requirement of the clamshell design and interface to have a measured gap. If it did look perfect would they be prone to creaking?

I've always wondered.

If the industrial design is prone to creaking or can't be produced with decent alignment / tolerances, than it's not an acceptable design for production, IMO.

Also, my comment applies to new 9100 DA cranksets as well as the replacements. They are all wonky.

[charliedid]

Originally Posted by Ttx1

If the industrial design is prone to creaking or can't be produced with decent alignment / tolerances, than it's not an acceptable design for production, IMO.

Also, my comment applies to new 9100 DA cranksets as well as the replacements. They are all wonky.

Without a doubt imperfect.

[tbike4]

Well this is a case of TLDR, 34 pages. I got around to looking at my 9100 crank and it has the "OK" letters on the arm so, apologies in advance, but can I get an easy synopsis of the procedure if I want to do something about it? Does the serial number mean anything?

Shimano web site says take it to a retailer. I found that part. BTW I have put a lot of miles on it with no issues.

Found a retailer, it's a Trek shop nearby with the words "Shimano inspection location" next to it. I have answered my own question I think.

[fa63]

Yep, "OK" falls in the recall so you would need to take it to a shop for an inspection. Good luck!

Originally Posted by tbike4

Well this is a case of TLDR, 34 pages. I got around to looking at my 9100 crank and it has the "OK" letters on the arm so, apologies in advance, but can I get an easy synopsis of the procedure if I want to do something about it? Does the serial number mean anything?

Shimano web site says take it to a retailer. I found that part. BTW I have put a lot of miles on it with no issues.

Found a retailer, it's a Trek shop nearby with the words "Shimano inspection location" next to it. I have answered my own question I think.

[Wunder]

Posting my own update on this. Now that the cold has set in I took my and my wife's road bikes into the LBS a week ago for inspection. Both have Ultegra 8000 cranksets old enough to be in this lot.

Her cranks checked out okay in the shop (limited mileage).

The crankset on my Cervelo R3 that have ~12,000 miles of all weather riding on them were showing signs of preliminary delamination on the driveside. They noted the non drive arm (with a Stages power meter installed) looked to be okay.

So I expect I will be getting at least half a new crank for my Cervelo. No word yet on timetable.

[cuda]

Originally Posted by dr_unix

Does anyone know what the actual spacing difference is? Is using a native 12-speed R8100 crank really that bad of an experience on an otherwise fully 11-speed bike?

Ive been riding a 12spd DA with a 11spd group for 6 months and no issues.
The 12spd crank will work on 11spd cassette provided you switch to a 12spd chain. In fact this is improves shifting slightly though it was never that much of an issue.

What some are complaining about is that the factory replacement crank is the 12spd crank arms with 11spd chain rings and have an aesthetic concern. Functionally there isn't any issue. It would have been nice for Shimano to send the crank with the 12spd chain rings but then everyone would complain that they now have to go and buy a 12spd chain. This is the least obtrusive solution imo because it solves the problem and you aren't out another $60 before you can use the replacement. And if the aesthetics bother you sell the 11spd rings and buy 12's and a chain.