Seraph Bikes Superlight 836g X68 - Alternative to SL8 Fakes?

[dovh]

This is really scary. I'm honestly beginning to regret my decision to purchase this frameset. Also, considering that my seat post cracked (most likely my fault, but anyway), seeing now this fork explode like this doesn't give me more confidence. Maybe Spcycle R088 would have been a better choice. Let's hope that this is a one-off..

By the way, what makes you think Tanan is completely outsourcing the production of this frame? Would it make sense to outsource something you can make in your own factory?

[jonathanf2]

What makes you think the r088 is any better? And please don't get me wrong, it's not meant as criticism. I have r088 on my way...

As mentioned, different fork, different head tube design, bigger headset bearings, etc. It's not trying to be a 1:1 SL8 copy in exchange for a more standardized and less proprietary design.

[Ultramic]

Aren't tantan, seraph, spcycle all the same mob ?

[BeR]

An AI report on this issue:

Fork Failure – Likely Root Cause Analysis (Assuming Third-Party Supplier Used by TanTan)

Following the failure pictured in this thread, I’ve examined both sides of the fork and would like to contribute a technical breakdown of likely causes. Based on the images and common carbon manufacturing practices, the failure appears to have originated internally and propagated rapidly under load — not due to external impact.

Key Observations:
   •   The failure occurred at the crown-leg junction — a known high-stress area during braking and compression.
   •   On the opposite leg, there’s clear evidence of buckling and laminate rupture, indicating a structural collapse rather than an isolated crack.
   •   The fractured edge shows signs of dry fiber and fraying, typical of resin starvation or poor resin impregnation.
   •   There’s no sign of crash damage, deep abrasions, or tire rub that might indicate impact-induced failure.

Most Likely Root Causes:
   1.   Resin Starvation or Poor Wet-Out
Some of the fractured zones appear to lack sufficient resin, which compromises fiber cohesion and structural strength. This is often due to inconsistent layup, inadequate vacuum pressure, or issues in resin application.
   2.   Delamination Due to Poor Layer Bonding
The visible peeling and frayed laminate suggest layers may have separated under stress. This can result from under-curing, improper consolidation, or temperature control issues during manufacture.
   3.   Crown-Leg Transition Weakness
This area is often difficult to mold uniformly, especially on molds reused heavily or not maintained correctly. Stress concentrations here would exploit any weakness in fiber orientation or bonding.
   4.   Manufacturing Quality Control Lapse
If TanTan uses a third-party frame/fork supplier (as is often the case), inconsistent quality control in the supply chain could allow defects like this to pass undetected — especially in lower-cost carbon production environments.

Additional Thoughts:
   •   This failure should not occur under normal riding loads, and it highlights the importance of proper QC, layup integrity, and resin content.
   •   If this was a one-off, it’s unfortunate. If others have similar forks, it might be worth proactively inspecting the crown-leg junction — particularly for signs of surface distortion or laminate stress.
   •   A post-failure ultrasonic or CT inspection would confirm voids or resin-poor zones, but visually this already looks like catastrophic laminate failure due to internal defects.

Serge, are you behind the AI ? Because, you talked about the lack of resin .

More seriously, have you got an answer from Tantan ?

It is unlikely but imagine if they have to recall a whole batch of frame because of this failure...

[Sebastian]

Thanks! This is normally achieved by this "sleeve"/"bushing"/"spacer" sitting on the axel, right? (in the DT 240/350 ratchet hubs it's the one with 15 mm inner diameter and 15,4 mm in length).
For this, I couldn't find any fitting shims so far Do you have any specific recommendations for where to find them?

In the serenade hub, this "sleeve" measures at 15,5 mm. Maybe a friend could turn one with 15,7 or so...

Did you buy this freehub new and I packaging? I converted a Serenade wheelset to N3W on my gravel bike and I’m pretty sure the original DT N3W freehub came with a sleeve and an end cap. It was a straight swap and worked right away.

[CoreX88]

Thanks guys! I reached out to Vivian via WhatsApp and TanTan via mail. They currently have week-long holidays due to Labor Day in China. However, couple days later I realize how lucky I have been. Usually I drive this route the other way round because you have a great high speed section at the beginning.

I'll keep you updated.

[makl]

Did you buy this freehub new and I packaging? I converted a Serenade wheelset to N3W on my gravel bike and I’m pretty sure the original DT N3W freehub came with a sleeve and an end cap. It was a straight swap and worked right away.

Yes, I bought it new. There was a new endcap but no sleeve included. Also DT Service wrote via E-Mail, that there's no other version of the sleeve that might fit. I think it was just poor tolerances, as mentioned before. 0.2 mm longer sleeve works fine now.

[TidyDinosaur]

It is unlikely but imagine if they have to recall a whole batch of frame because of this failure...

They won't do a recall since there is absolutely no risk to them for a lawsuit...
Chinese sellers are above the (western) law, so it's up to their goodwill if they will give you warranty replacements or some money back when something goes wrong... And if sh*t really hits the fan they will just ignore you and the problem is solved for them.

[Sander2177]

Chinese seller are not above Chinese law however and this can still be pursed but the question is wether it is will work:

Just to add some context — China does have an official regulatory body that oversees product safety and quality. It’s called the State Administration for Market Regulation (SAMR) — or in Chinese, 国家市场监督管理总局.

Website: http://www.samr.gov.cn (Chinese only, but Google Translate works fine)

They’re responsible for handling issues like defective products, manufacturing violations, and recalls, including in cases where a product poses a safety risk. While they’re not specifically set up for international consumers, it is technically possible to submit a complaint — though you’d need to do it in Chinese or get it translated.

Also, every city in China has its own local market supervision bureau (like a regional SAMR branch), which may be more responsive depending on where the seller or factory is based — e.g. Shenzhen or Xiamen.

Of course, whether they act on it is another matter, especially for a one-off case, but Chinese businesses generally don’t want regulatory trouble. Just mentioning SAMR in your communications can sometimes be enough to make a seller take a claim more seriously.

If nothing else, it’s good to know there is an official channel beyond just PayPal or the seller’s goodwill.

[Sander2177]

However many of us have used PayPal do this is the best option if they are not responding etc.

Just to clarify for anyone in the same situation — if the fork failed during normal riding and not as a result of shipping damage, it can still be pursued through PayPal under a “Significantly Not as Described” (SNAD) claim.

The key point is that the product was inherently defective and failed under typical use, which makes it unsafe and unfit for its intended purpose. PayPal does allow for disputes in cases like this, especially if there’s clear evidence the item had a manufacturing flaw.

Photos of the failure, a description of the conditions when it happened (e.g. no crash, no misuse), and even informal input from a mechanic can help support the case. Most buyers here have used PayPal, so it’s a good safety net — you’re not completely at the mercy of the seller’s goodwill.

Also, for what it’s worth, I’m the sort of person who wouldn’t just let this slide. I wouldn’t pursue legal action obviously, but I’d definitely go down the route of PayPal or other buyer protections if needed

[LowPaceKingdom]

JUST FOR INFO

Mine ttx 68 (white waved wheels)

alrdy    1000km on it
speed:  25-33km/h
           95% road / used pavement cracks / fixed cracks
           5% gravel

issues is BB is creaking on higher watt output (but not always)  -   will check if bb is greased ......
Handlebar spacer rubbing / grinding  on  frame so the paint in a little area  under the spacer  is gone / scrachted

no fatal issues so far

[CoreX88]

Already got feedback from TanTan (Vivian).

1. They will conduct an in-depth investigation into the fork issue of the TT-X68.
2. After doing so and finding the root cause of this material problem (if there is any) they will sent out a new and painted fork.
3. From the pictures provided they stated the frame looks ok and should be safe to ride, but checking every mm visually plus doing the "coin" test should be the next step from my side. In any case of noticable damage I should get back.

Lets see...

[Serge_K]

Serge, are you behind the AI ? Because, you talked about the lack of resin .

Hehe. If you look at a steerer tube, or carbon bits like a derailleur cage, versus the photo of the shattered fork, and then look at videos from people who use non pre preg carbon (easy composites UK on yt, for eg), the fork looks like it's basically carbon strands without enough resin. If you brake a steerer in two, you don't have long loose strands like that, it's more like a crunchy chocolate bar with a matrix of chocolate and crunchy bits in it. That fork looks like it's all crunchy bits and no matrix. And the only reason why carbon fiber is strong is the resin matrix. The fibers are useless without it.

So, here, we have ultra light frames, seatposts that crack, forks that implode, BBs that creak from new, how many more elements do we need to get a mental model of how tight a ship tamtam is running?

Also, if you almost die on that bike, and it's a counterfeit, as your insurance company, I'd probably say that you're on your own.

JUST FOR INFO

Mine ttx 68 (white waved wheels)

alrdy    1000km on it
speed:  25-33km/h
           95% road / used pavement cracks / fixed cracks
           5% gravel

issues is BB is creaking on higher watt output (but not always)  -   will check if bb is greased ......
Handlebar spacer rubbing / grinding  on  frame so the paint in a little area  under the spacer  is gone / scrachted

no fatal issues so far

Lol. Had there been a fatal issue, by definition, you'd be posting on the forum from heaven. Pretty sure hell doesn't have wifi.
Creaky BB so early on is likely either user error, or poor manufacturing tolerances. Or both.


All of that from a lust for specialized vibe. Marketing done well.

[glepore]

Its not necessarily "no resin" fwiw. Its more likely insufficiently heated prepreg. Result is the same though.

Its not encouraging that it happened, but lets see what the response is.

I don't doubt that the large demand for the frame has stressed production and probably qc. I also believe that tantan and other larger companies monitor social and even this forum for feedback.

[Sander2177]

Serge, are you behind the AI ? Because, you talked about the lack of resin .

More seriously, have you got an answer from Tantan ?

It is unlikely but imagine if they have to recall a whole batch of frame because of this failure...

No, it was Serge who made the comment about the resin. I use AI/ChatGPT as a resource, which has been incredibly helpful for handling similar customer service situations—though my experiences are based in the UK which is obviously an awful lot different to China!