Is this I9 hub failing?

stb222

Love Drunk
Jerk Squad
IMG_1898.jpeg

The original axle and the warranty replacement, you can see they changed it up, how the inner race interacts on the drive side with a washer. I’m not really sure what the thought behind having the washer there is instead of machining it and I measured with my calipers to make sure it was the correct width and it was, so who knows . The guy that did the warranty claim said that they have a revised axle in the works, so I’m wondering if they had issues with this one as well.
 

Santapez

Well-Known Member
Team MTBNJ Halter's
That's a bad way to design a stepped axle as there's a stress riser in the middle of the axle, both old and new design. New design may provide more support so it has less stress, but it's still bad. I'm going to assume that the step in the axle is right where there's some play from the freehub concentrating the highest load right on that point.

That setup may actually be stronger having a two piece design with it being a tube with the smaller OD all the way through with the bearing spacer being another tube that slides over it.

Carroll Smith is spinning in his grave.
 

Karate Monkey

Well-Known Member
That's a bad way to design a stepped axle as there's a stress riser in the middle of the axle, both old and new design. New design may provide more support so it has less stress, but it's still bad. I'm going to assume that the step in the axle is right where there's some play from the freehub concentrating the highest load right on that point.

That setup may actually be stronger having a two piece design with it being a tube with the smaller OD all the way through with the bearing spacer being another tube that slides over it.

Carroll Smith is spinning in his grave.

We figured this out with freewheels all the way back, and the design revision (freehubs) to stop it from happening.

Then apparently went right back to it when cartridge bearings became common.

Maybe there's a nice fillet under the spacer?
 

Santapez

Well-Known Member
Team MTBNJ Halter's
We figured this out with freewheels all the way back, and the design revision (freehubs) to stop it from happening.

Then apparently went right back to it when cartridge bearings became common.

Maybe there's a nice fillet under the spacer?
I assumed there's no fillet as it probably mates right up to another bearing and it's a 90 degree cut in the axle.

Should just have the axle made out of stainless with an aluminum spacer between the bearings... Probably less time on CNC machines, but not as pretty and another SKU.

I dunno, I'm not an engineer. :)
 

stb222

Love Drunk
Jerk Squad
I assumed there's no fillet as it probably mates right up to another bearing and it's a 90 degree cut in the axle.

Should just have the axle made out of stainless with an aluminum spacer between the bearings... Probably less time on CNC machines, but not as pretty and another SKU.

I dunno, I'm not an engineer. :)
The sidewall thickness is too thin also.
IMG_1935.jpeg

This is a project 321 axle, thicker wall thickness. I guess the potential downside of this is there is no seat for the inner race on either side. Probably explains why these spin way easier than i9 😂
 

one piece crank

Well-Known Member
Happy to report that operation Silence of the Lambs is a complete success. As a summer wheelset, the past two morning upper-30's temps were enough to validate the now silent i9 XD Torch driver.
After a few hundred miles I noticed the buzz started to return. Only about 10-20% of full I9 volume, so still quiet. Then next ride it was back to near silent. I think the Tenacious Oil is doing its job!
 

jShort

2018 Fantasy Football Toilet Bowl Lead Technician
Team MTBNJ Halter's
I’ll just stick to the Toyota Camry of hubs: The DT350. I can’t take credit for that reference, but it’s accurate.

And I’ll also stick with 36t of engagement and never worry about the walk of shame due to a failed freehub.
 

Santapez

Well-Known Member
Team MTBNJ Halter's
The ball & socket "fix" they have is pretty much exactly what I said they should do, however it's way shorter of a collar than I would expect.

I’ll just stick to the Toyota Camry of hubs: The DT350. I can’t take credit for that reference, but it’s accurate.

And I’ll also stick with 36t of engagement and never worry about the walk of shame due to a failed freehub.
I applaud anyone who can be OK with 36T, I personally find it frustrating. But super high engagement I don't feel is necessary or worth adding all the complexity. It's not hard to do a reliable 6-pawl design with 72 points or so.

But bigger=better for everyone it seems and that slightly higher engagement isn't what people want, it's 4,000 clicks per rotation. Can anyone say a Hydra hub improves their riding over the lower engagement 1:1 hub from I9? The 1:1 still has a ton of engagement.
 

Steve Vai

Endurance Guy: Tolerates most of us.
I’ll just stick to the Toyota Camry of hubs: The DT350. I can’t take credit for that reference, but it’s accurate.

And I’ll also stick with 36t of engagement and never worry about the walk of shame due to a failed freehub.

I run them on every bike I own except the Fat Bike. Absolutely the best hubs on the planet. And never, ever, ever put a 56t ratchet in unless you plan on walking out of the woods every other ride.
 

serviceguy

Well-Known Member
I run them on every bike I own except the Fat Bike. Absolutely the best hubs on the planet. And never, ever, ever put a 56t ratchet in unless you plan on walking out of the woods every other ride.
56T ratchet is the $3 bills of DT Hubs, may explain why they keep failing...
 

stb222

Love Drunk
Jerk Squad
I run them on every bike I own except the Fat Bike. Absolutely the best hubs on the planet. And never, ever, ever put a 56t ratchet in unless you plan on walking out of the woods every other ride.
Given how DT SWISS engagement works, why does the increased engagement fail on their design?

Also, as soon as they’re available, and I can scrounge up the funds, going back to project 321, V2 hub is a smoothest hub I’ve ever had
 

Steve Vai

Endurance Guy: Tolerates most of us.
Given how DT SWISS engagement works, why does the increased engagement fail on their design?

Also, as soon as they’re available, and I can scrounge up the funds, going back to project 321, V2 hub is a smoothest hub I’ve ever had

The 56t rachet has more teeth in the same sapce so each tooth is shallower. They basically go totally smooth when they fail.
 

John the Plumber

Active Member
When I went with new wheel build I went with the 36T because I read up on both. They said you want less engagement on a MTB for reliability. on a road bike go with the
56T. It made sense to me and I have about 3500 miles on the hubs.
 

TommyF

Well-Known Member
I'm on my 3rd set of bearings for that hub in less then 2 years. Axle is still original and looked okay when the bearings were done about 2 weeks ago. I do like the hub, but probably wouldn't go the I9 route again if it totally failed. The front I9 failed last year, it cracked right where the spoke hooks on, I did not replace it with another I9.

The new Santa Cruz I just purchased comes with DT-Swiss so I'm a happy camper there !!!
 
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