[Cryak]

I finally got my hands on a large 2021 Kona Kahuna in Aug of this year, which came with WTB ST i27 TCS 2.0 rims.
I was riding on a flat trail, went to hop up on a low ladder over a stretch of mud, caught the back tire on the front edge of the ladder, and 5 min later my rim looks like this:

I used to ride a lot harder when I was younger on trails, dirt jumps, ladders, and even skate parks.
I can't remember ever seeing a rim split so easily.
I also only weigh 160 lbs.
The employee at the shop I purchased from was very dismissive, saying it was due to impact and that was that.
My question to the community is: is it common for this quality of rim to split due to a moderate impact?
I have been away from avidly biking for almost 10 years, so I'm unsure.
Thanks in advance for any insights.

 

[*OneSpeed*]

That is a tire pressure/rider error failure. That thing took a serious hit, Not the rims fault.

It's mountain biking and Sh*t happens, but common, don't blame the rim.

 

[noapathy]

The fact that the tube still held pressure is kind of amazing, but yeah...
Sorry about the wheel. It sucks, but happens sometimes when you smack into sharp-edged stuff in just the wrong way. Maybe 9 times out of 10 nothing happens, but eventually you get this type of failure.

 

[Rod]

That is a tire pressure/rider error failure. That thing took a serious hit, Not the rims fault.

It's mountain biking and Sh*t happens, but common, don't blame the rim.

This is spot on. You hit a square edge with too low of pressure and the rim took the impact. Time to learn how to lace a new rim. FYI, square edge hits are the worst and they will destroy your rims with ease.

As Noapathy said, I'm amazed you didn't get a pinch flat upon that impact.

 

[Bassmantweed]

Agree. 100% not rims fault.

 

[s0ckeyeus]

I was expecting a small split at the seam, honestly, and not a rim destroyed by impact. I'm with everyone else. It sucks, but it's not a warranty issue or the rim's fault.

 

[jeremy3220]

Either way some rims are stronger than others. Not sure about these particular rims though.

 

[Bicycle Rider]

I would agree with all above, regarding technique/ line choice and tire pressure. And not a warranty issue.
But when you get that rim replaced, sure might as well pick a stronger / heavier replacement!

 

[mikesee]

The ST rims are low-end WTB, and WTB doesn't make much that could be called high end.

Still, it seems unlikely that a love tap as described could cause what's pictured.

 

[jrhone]

Just curious...what pressure were you running? It looks like a very low pressure and a hard hit...sorry about that.

 

[slimat99]

I would expect no more than a dent from what you're describing. I don't know anything about your rim, but some OEM stuff is total junk. There are def some OEM rims made of Swiss Cheese.

As far as people saying it's a riding technique issue. Come on guys. Everyone knows you're not supposed to bang into square edges but these things happen. Even cheap lightish rims should be able to shrug off what he's describing. My guess is there was a stress crack that gave. Rims just don't crater like this from something so benign. Could also be a manufacturing defect but my money is on a stress crack.

 

[DeeCount]

If you're over 215lb-ish I would say it's an overloaded rim with probably inadequate tire pressure for the hit. SInce you're 160lb-ish I would guess it's a defective rim. That WTB ST series is an entry level, price-point, sleeved, OEM only rim as @mikesee mentioned. The WTB KOM Light or KOM Tough would serve you better.

 

[FrankS29]

I could be wrong as I'm not 100% on wheel dynamics, but the fact that it's completely caved in like that tells me there was a massive amount of force put into that specific spot on that rim, stress crack or not.

 

[dundundata]

Can't say I've had that happen

 

[*OneSpeed*]

If you're over 215lb-ish I would say it's an overloaded rim with probably inadequate tire pressure for the hit. SInce you're 160lb-ish I would guess it's a defective rim. That WTB ST series is an entry level, price-point, sleeved, OEM only rim as @mikesee mentioned. The WTB KOM Light or KOM Tough would serve you better.

I have i30 ST rims on my Kona Process 134 trail bike. I beat on that thing pretty hard and never even dented the rim. But, I also know to run the proper tire pressure and I'm tubeless. (6'3" 215 lbs, not gentle)

 

[noapathy]

You guys know just as well as I do...just because the rim broke that ride doesn't mean that's when the majority of the damage occurred. JRA strikes again!

 

[hellride]

I finally got my hands on a large 2021 Kona Kahuna in Aug of this year, which came with WTB ST i27 TCS 2.0 rims.
I was riding on a flat trail, went to hop up on a low ladder over a stretch of mud, caught the back tire on the front edge of the ladder, and 5 min later my rim looks like this:
View attachment 1959192
I used to ride a lot harder when I was younger on trails, dirt jumps, ladders, and even skate parks.
I can't remember ever seeing a rim split so easily.
I also only weigh 160 lbs.
The employee at the shop I purchased from was very dismissive, saying it was due to impact and that was that.
My question to the community is: is it common for this quality of rim to split due to a moderate impact?
I have been away from avidly biking for almost 10 years, so I'm unsure.
Thanks in advance for any insights.

I gathered this was an ongoing issue with there rims, specifically cracking and splitting at the spoke holes. While as many people have referenced its mountain biking and it can happen... The fact that your inner tube is still inflated is very strange, and its also very odd the rim wall appears to be fully intact as that would normally bend in, in the many experiences i have destorying rim. Also the fact they were replacing all of their rims over the past few years without much question. I'd give this pause.

 

[dundundata]

As long as it holds air...

 

[slimat99]

I just noticed this small crack today. I'm positive the impact that caused this dent where the crack propagated from didn't crack the rim. A few days of literally JRA caused the crack. I can't say what caused it because nothing but normal riding with no big rim pings has taken place since the dent.

This is how the vast majority of my rims end their life. They don't get knocked out with an uppercut, they get TKO'd in the 12th round after eating too many jabs and hooks. I almost got a full year out of this rim. A little shorter than average life span for me but not too far off the norm. Rim is an ex471, and I didn't flat from the original dent, or whatever impact finally cracked it. Counter intuitive things happen.

 

[749800]

That will buff right out. A little bit of rim tape and it will be just like new.