Carbon Wheel Failure!!! 😲😟😭

RustyIron

E*POWAH Elite World Champion
Subscriber
Jun 5, 2021
1,865
2,925
La Habra, California
Are ALL carbon rims prone to failure, or just Trek's?

Yesterday our crew hit the Palm Canyon Epic, a noteworthy trail outside Palm Springs, California. After our extremely wet winter, the desert had plenty of stream crossings and a carpet of wildflowers. But that's a tale for another time.

One section of trail is several miles of double black diamond. It's hella chunky with sharp volcanic rock, narrow lines, and serious exposure. Failure here would be ill advised. But it was all good, and everyone had a great time.

We got back to town, loaded up the trucks, and grabbed a bunch of tacos and beer. Ride. Tacos. Beer. As we moseyed on back to the trucks, someone pointed to one of the bikes and exclaimed, "WTF happened here?!"

The bike belonged to our best rider. The dude is fast. He hits it hard. And he was on his second beer before the rest of us got to the pub. Examination of the front wheel revealed a small chunk of volcanic rock that had penetrated the rim and was stuck there. No air was lost, no cracks had propagated, and the wheel ran as if it was brand new.

What do you think? A bit of nail polish to smooth it out? Slap a sticker over it and pretend it never happened?

IMG_0495.jpeg
 

withersea

New Member
Apr 2, 2023
22
39
Leeds, UK
I think that's classed as an unfortunate meeting between something from mother nature and something man made.

I'd replace the rim, you could never ride it again with total confidence and any wheel failure. Be it carbon or aluminium is catastrophic if the rim is damaged.
 

Paulquattro

E*POWAH Elite
May 7, 2020
2,351
1,302
The Darkside
I think that's classed as an unfortunate meeting between something from mother nature and something man made.

I'd replace the rim, you could never ride it again with total confidence and any wheel failure. Be it carbon or aluminium is catastrophic if the rim is damaged.
I agree with the above ^^
I wouldn't class that as a failure
But as rightly said i wouldn't run it either .
 

Mteam

E*POWAH Elite
Aug 3, 2020
1,883
1,820
gone
Hard to tell from photos, but I'd inspect it more closely,and if it looks as superficial as it appears in the images I'd just smooth out the jagged edges with some sandpaper, fill with epoxy resin and ride it.

I'd keep a close eye on it for a few rides and assuming it didnt get any worse I'd forget about it.
 
Last edited:

Plummet

Flash Git
Mar 16, 2023
1,152
1,635
New Zealand
That is not carbon wheel failure. You have smashing it into rocks.....
Its operator induced carbon wheel damage. Don't blame Trek or the carbon wheel. Blame yourself for smashing it into rocks.

Sorry, I do get a bit of old man rage at people blaming their gear for their own riding errors.

I would probably slap a repair on there. The rock has penetrated into the structural layers.

You can see my carbon wheel repair here.
 

Expidia

Well-known member
Jun 27, 2022
548
440
Capital Region, New York
Thing is if you crash and smack your helmet the manufacturer warns to replace it. Some will even replace it for free during the first year, I think I read that.

Riding any damaged wheel is just a recipe for a disaster :eek:
 
Last edited:

Rod B.

Well-known member
Aug 18, 2021
532
926
USA, Orange County Ca.
The conditions on the Palm Canyon Epic were the best I’ve ever seen. It was a great ride. Rusty and I opted to go down the Art Johnson trail instead of Hahn-Buena Vista to Cathedral. The Art Johnson was also in great condition.

Here’s another picture of the rim. It’s a total write off. I’d mount it over the work bench and call it a conversation piece. You don’t see an arrowhead shaped rock sticking out of a carbon rim very often.

1680968907807.jpeg
 

cappuccino34

Active member
Nov 24, 2020
530
329
Helmshore
Are ALL carbon rims prone to failure, or just Trek's?

Yesterday our crew hit the Palm Canyon Epic, a noteworthy trail outside Palm Springs, California. After our extremely wet winter, the desert had plenty of stream crossings and a carpet of wildflowers. But that's a tale for another time.

One section of trail is several miles of double black diamond. It's hella chunky with sharp volcanic rock, narrow lines, and serious exposure. Failure here would be ill advised. But it was all good, and everyone had a great time.

We got back to town, loaded up the trucks, and grabbed a bunch of tacos and beer. Ride. Tacos. Beer. As we moseyed on back to the trucks, someone pointed to one of the bikes and exclaimed, "WTF happened here?!"

The bike belonged to our best rider. The dude is fast. He hits it hard. And he was on his second beer before the rest of us got to the pub. Examination of the front wheel revealed a small chunk of volcanic rock that had penetrated the rim and was stuck there. No air was lost, no cracks had propagated, and the wheel ran as if it was brand new.

What do you think? A bit of nail polish to smooth it out? Slap a sticker over it and pretend it never happened?

View attachment 110750
That's not rim failure, that's rim damage.
 

Plummet

Flash Git
Mar 16, 2023
1,152
1,635
New Zealand
The conditions on the Palm Canyon Epic were the best I’ve ever seen. It was a great ride. Rusty and I opted to go down the Art Johnson trail instead of Hahn-Buena Vista to Cathedral. The Art Johnson was also in great condition.

Here’s another picture of the rim. It’s a total write off. I’d mount it over the work bench and call it a conversation piece. You don’t see an arrowhead shaped rock sticking out of a carbon rim very often.

View attachment 111171
Its not a right off if you don't want it to be. it could be quickly patched and you could ride it like you stole it for a while yet.
 

Sunburntwily

Member
Jan 28, 2021
95
52
Australia
That's not a failure. It's still true isn't it. Carbon fibre totally repairable. If anything I'd say it demonstrates just how good they are. However they do come with a sticker on the rims stating that they wear out. I have never seen that on other bike rims.
 

cozzy

E*POWAH Elite
Subscriber
Aug 11, 2019
941
1,056
Hampshire UK
I smashed my Santa Cruz reserve today on rocks whilst on holiday. Fortunately I bought the original alloy wheels with me.
Stuff goes wrong, no worries. I'll be testing out their lifetime warranty when I get home.
They lasted 4.5 years and have only ever broken a couple of spokes until now.
Wonder if I'll be able to upgrade these original rims to the 32 spoke DH rim?

IMG_20230712_151013.jpg
 

Julie_X1

Active member
Jan 22, 2023
141
116
Canada
Thing is if you crash and smack your helmet the manufacturer warns to replace it. Some will even replace it for free during the first year, I think I read that.
Thing is if you crash and smack your helmet the manufacturer warns to replace it. Some will even replace it for free during the first year, I think I read that.

Riding any damaged wheel is just a recipe for a disaster :eek:
Yes, Bontrager (Trek) helmets have the 1-year replacement-in-case-of- crash guarantee.

Trek also offers 2 years crash replacement on their carbon wheels:

“Additionally, every set of Bontrager carbon wheels is backed by the Carbon Care Wheel Loyalty Program, which provides free repair or replacement in the unlikely event you structurally damage your wheels while riding within the first two years of ownership (and deeply discounted rebuild or replacement to the original owner regardless of the date of purchase).”
 

Sunburntwily

Member
Jan 28, 2021
95
52
Australia
My Chinese carbon rims had a sticker essentially saying these wheels will wear out over time. They are Chinese rims no doubt made in the same place as any other carbon rims. They definitely look the part offset spokes etc, and I didn't pay a lot for them. I'm impressed with them but just thought it was interesting that they say "will wear out".
 

Cell4soul

E*POWAH Master
Jul 11, 2022
518
1,325
Mesa, AZ
I wouldn’t trust that rim. Failure on the wrong section of trail could be catastrophic. The cost of a new rim is well worth my safety.

I was thinking bout riding Palm Canyon Epic this fall. I would be riding alone. Would it be unwise to do this trail on a solo ride?
 
Last edited:

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

559K
Messages
28,288
Members
Join Our Community

Latest articles


Top