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

[glepore]

I already follow this thread for a long time and I am aware of the issues in the past. However it seems to be hard to find another frame which is light and still is quite aero like this one.

Will the XM Carbon Speed wheels with 26mm internal 34 external paired with a GP5000 32mm fit in this frame?
Did anyone ride light gravel with this frame?

Its highly tire dependent. I have the same wheels and run Vittoria Corsa Controls in 30 and they measure out to a little over 31 with room to spare. Patrick did a youtube video with XMCS wheels and gp5000 32's on an actual sl8 so suppose it works.

As to gravel, the frame is durable enough for me at 60kg to run a couple miles of light gravel on some of my road rides. I wouldn't use it as a "gravel bike" but I've had no issues with those wheels (with carbon spokes) and the x68 (with the early, lighter fork) on mixed surface routes.

As to Sander's comments, I'd not run 28's tubeless on a 25-26 rim, but a) I don't like road tubeless and b) the xmcs wheels are hooked and likely ok with that width but handling might not be optimal

[klrdd]

My 25mm inner width wheels with 28mm tyres measure 31.7mm.

On my XMC wheels with 24mm IW, the same 28mm tyre measures 30.7mm.

Personally, I wouldn’t run a 28mm tyre on 26mm IW either. Even the 28mm on 25mm IW feels borderline to me—unless someone can prove me wrong.

A 30mm on 26mm IW might work if some has tried it, I think a 32mm would probably be too tight for my liking.

28mm tyre on 24mm IW → ~30.7mm
28mm tyre on 25mm IW → ~31.7mm
28mm tyre on 26mm IW → ~32.5mm
30mm tyre on 24mm IW → ~31–31.5mm
30mm tyre on 25mm IW → ~31.5–32mm
30mm tyre on 26mm IW → ~32.5–33mm
32mm tyre on 24mm IW → ~33–33.5mm
32mm tyre on 25mm IW → ~33.5–34mm
32mm tyre on 26mm IW → ~34.5–35mm

Depending on tyre model I run maxxis High Road SLs

How do you feel about the 2024 ETRTO standards recommending not to use 28mm tyres with 24mm IW and higher? I'm not planning to run such skinny tyres with my incoming 24m IW hoops (thinking 32 if not 35mm -- shitty roads around here), but just wondering...

EDIT: For reference, from continental: https://www.continental-tires.com/products/b2c/tire-knowledge/tire-rim-combinations-etrto-standards/

[cramy]

HI,

Did you weigh both bikes?

not yet will do it in 2 weeks when i am back.

[Sander2177]

How do you feel about the 2024 ETRTO standards recommending not to use 28mm tyres with 24mm IW and higher? I'm not planning to run such skinny tyres with my incoming 24m IW hoops (thinking 32 if not 35mm -- shitty roads around here), but just wondering...

EDIT: For reference, from continental: https://www.continental-tires.com/products/b2c/tire-knowledge/tire-rim-combinations-etrto-standards/

I’ve honestly never even looked at the ETRTO standards—and as you said, it’s a recommendation so not a hard-and-fast rule.
I was running 28mm tyres on 25mm IW with no issues at all, so I feel confident in judging what works based on experience.

[Sander2177]

I already follow this thread for a long time and I am aware of the issues in the past. However it seems to be hard to find another frame which is light and still is quite aero like this one.

Will the XM Carbon Speed wheels with 26mm internal 34 external paired with a GP5000 32mm fit in this frame?
Did anyone ride light gravel with this frame?

From a member on Weight Weenies

I have 30mm GP 5K S TR installed on my XMCS 26mm IW rims they measure 33mm @ 50 psi

[klrdd]

I’ve honestly never even looked at the ETRTO standards—and as you said, it’s a recommendation so not a hard-and-fast rule.
I was running 28mm tyres on 25mm IW with no issues at all, so I feel confident in judging what works based on experience.

Thanks. I had never looked at it either until I was listening to the Nero Show's interview with a Continental product manager over the weekend. Not very information dense, but her perspective was interesting despite some insipid lines of questioning from the boys:

[patliean1]

I already follow this thread for a long time and I am aware of the issues in the past. However it seems to be hard to find another frame which is light and still is quite aero like this one.

Will the XM Carbon Speed wheels with 26mm internal 34 external paired with a GP5000 32mm fit in this frame?
Did anyone ride light gravel with this frame?

I've fit 32c GP5000 on my genuine Tarmac SL8 with the same XM Carbon Speed wheels with 26mm internal 34 external no problem. The tires stretch to around 34mm at the rim.

https://youtu.be/BtuLvRT1u-c?si=XtC1aiMUr91yt2AA

[SkylarRnD]

She has been built.

Ive taken her for a few rides now and have some perspective. The build was a breeze. Everything routed internally crazy smooth, the BSA threads were a dream and the thru axles are the same. I took a file to the brake mounts and tried to remove the overspray as neatly as possible. The brakes mounted very flat. I had to source the front mount brake adapter from a local shop(they actually removed it from an Aethos they had so I could get my build done quickly). Ill go through a parts list and then give impressions.

My specs: 188cm tall, 91.4cm inseam,and I weigh 74-76kg

Frame: X68(duh) in a size 56
Handlebars: Ullicyc T4 Ultimate 36/120
Wheel: 9Velo CD Wide 50/58(ceramic bearings and Ti freehub)
Groupset: SRAM Force E1 w/PM. 10/36 cass and 48/35 chainrings. 160mm Paceline rotor front. 140 CLX-R rotor rear
Chain: SRAM 12spd Flat top. Purple. Waxed.
Saddle: Ryet 3D Romin copy...picture has Selle Italia SLR
Pedals: Onirii Ti extended SPD-SL(maybe switching to Ultegra 4mm extended)
Der Hander: Silca 3d Ti
Tires: Pirelli Pzero Race TLR RS 30mm setup tubeless with Silca 2.0 and RideNow valves(just slashed my tire open on my last ride...8mm cut in my brand new tire. Sealant everywhere....yay)

First impressions: the bike feels super compliant. It sprints quickly and gets up to speed faster than I can. Turning is a dream and sharp as a tack. I am in love with the internal cable routing and it looks so stupid clean.

Going downhill is another story. Its sloppy at high speeds. I recently went on a fast group ride and above 38mph it was a bit sketchy. Going dead straight downhill wasnt bad but cornering as speeds felt unstable. I am not the best descender or corner taker. I'd love some insight if anyone else feels this way or if I set it up poorly for descending, obviously a longer wheelbase would be more stable. I did put my saddle back a few mm today to test the weight balance, Ill report back.

I did go 52mph down a rippin hill and passed some real fast bois tho, so that was fun.

[glepore]

I've read complaints from some on ww and other forums about the real sl8's stability in high speed corners. Others swear its rock solid. My (highly personal) suspicion is that the bike/geo is sensitive to weight distribution, and the aggressive position some folks have leads to a rearward weight bias.
Looking at your photo, it appears you're on the smallest frame that would fit, which is great for liveliness and acceleration, but the amount of drop you have is likely compensated for by a slightly shortish stem, biasing weight rearward. Again, not a fitter and just a WAG.

[SkylarRnD]

I've read complaints from some on ww and other forums about the real sl8's stability in high speed corners. Others swear its rock solid. My (highly personal) suspicion is that the bike/geo is sensitive to weight distribution, and the aggressive position some folks have leads to a rearward weight bias.
Looking at your photo, it appears you're on the smallest frame that would fit, which is great for liveliness and acceleration, but the amount of drop you have is likely compensated for by a slightly shortish stem, biasing weight rearward. Again, not a fitter and just a WAG.

I have a 120mm stem. My saddle at the time was slightly forward of center.

[Kar25]

She has been built.

Ive taken her for a few rides now and have some perspective. The build was a breeze. Everything routed internally crazy smooth, the BSA threads were a dream and the thru axles are the same. I took a file to the brake mounts and tried to remove the overspray as neatly as possible. The brakes mounted very flat. I had to source the front mount brake adapter from a local shop(they actually removed it from an Aethos they had so I could get my build done quickly). Ill go through a parts list and then give impressions.

My specs: 188cm tall, 91.4cm inseam,and I weigh 74-76kg

Frame: X68(duh) in a size 56
Handlebars: Ullicyc T4 Ultimate 36/120
Wheel: 9Velo CD Wide 50/58(ceramic bearings and Ti freehub)
Groupset: SRAM Force E1 w/PM. 10/36 cass and 48/35 chainrings. 160mm Paceline rotor front. 140 CLX-R rotor rear
Chain: SRAM 12spd Flat top. Purple. Waxed.
Saddle: Ryet 3D Romin copy...picture has Selle Italia SLR
Pedals: Onirii Ti extended SPD-SL(maybe switching to Ultegra 4mm extended)
Der Hander: Silca 3d Ti
Tires: Pirelli Pzero Race TLR RS 30mm setup tubeless with Silca 2.0 and RideNow valves(just slashed my tire open on my last ride...8mm cut in my brand new tire. Sealant everywhere....yay)

First impressions: the bike feels super compliant. It sprints quickly and gets up to speed faster than I can. Turning is a dream and sharp as a tack. I am in love with the internal cable routing and it looks so stupid clean.

Going downhill is another story. Its sloppy at high speeds. I recently went on a fast group ride and above 38mph it was a bit sketchy. Going dead straight downhill wasnt bad but cornering as speeds felt unstable. I am not the best descender or corner taker. I'd love some insight if anyone else feels this way or if I set it up poorly for descending, obviously a longer wheelbase would be more stable. I did put my saddle back a few mm today to test the weight balance, Ill report back.

I did go 52mph down a rippin hill and passed some real fast bois tho, so that was fun.

She is good looking 😉
How much does she weight?

[Tpower59]

I've fit 32c GP5000 on my genuine Tarmac SL8 with the same XM Carbon Speed wheels with 26mm internal 34 external no problem. The tires stretch to around 34mm at the rim.

https://youtu.be/BtuLvRT1u-c?si=XtC1aiMUr91yt2AA

Same for me
At what PSI do you inflate them ?

[SkylarRnD]

She is good looking 😉
How much does she weight?

Thank You! She weighs 7.4kg. Bars are heavy for the spec, they have a wedge style attachment that could be lighter and a few other things too. Im guessing I could get this below 7kg for sure.

[JImportante]

I have to change my handlebar..
Any recommendations?  nothing super expensive ofc

[Lotnik]

I have to change my handlebar..
Any recommendations?  nothing super expensive ofc

Fake Darimo looks good with fake SL8