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

[patliean1]

This listing just feels dodgy.

https://tantanbikes.com/Ink-Green-Paint-24-Speed-Disc-Brake-Road-Bike-TT-X42-Carbon-Normal-Wheels-Wheeltop-Hydraulic-Electronic-Shifting-p6565762.html

NOTE: The bike stand pictured is not included.

[Peklatin]

Interested in buying a complete bike. Is their real domain tantanbikes.com or tantanbicycles.com?

[Tijoe]

Price is good for their blend of components, but to me, the bike is heavy.  My old Scott addict clocks in at about 15.5 lbs.  This TanTan seems heavy to me.

[SkylarRnD]

This bike sucks down hill. I have no idea why Im getting such a wobbly, uncontrolled feeling. I just threw on a buddies carbon wheelset and went up and down a local hill where I can get up to 40mph. Around 30 it feels like a wiggly noodle while cornering. It starts to shake at 32mph and I have to gently pull the rear brakes. Wheels are balanced well, headset is snug with zero play. Ive tried the knees on the top tube, shifting my weight fore and aft, pedaling constantly,  and keeping my weight off the saddle and only on the outside pedal...nothing helps.

Ive reached out to Vivian to see if she may have an answer bc it feels very unstable and unsafe.

Anyone else figure this issue out?

[Mario kart]

This bike sucks down hill. I have no idea why Im getting such a wobbly, uncontrolled feeling. I just threw on a buddies carbon wheelset and went up and down a local hill where I can get up to 40mph. Around 30 it feels like a wiggly noodle while cornering. It starts to shake at 32mph and I have to gently pull the rear brakes. Wheels are balanced well, headset is snug with zero play. Ive tried the knees on the top tube, shifting my weight fore and aft, pedaling constantly,  and keeping my weight off the saddle and only on the outside pedal...nothing helps.

Ive reached out to Vivian to see if she may have an answer bc it feels very unstable and unsafe.

Anyone else figure this issue out?

Do the handlebars turn freely? I once had an issue where headset and frame rubbed, this was enough to throw the stability off. Crazy such a small amount of rubbing resists the self centering of the front wheel

[glepore]

Do the handlebars turn freely? I once had an issue where headset and frame rubbed, this was enough to throw the stability off. Crazy such a small amount of rubbing resists the self centering of the front wheel

May be something to that, all of the stock covers seem to have some friction with the headtube.

I've not had the issue at all so can't help. Mine's been rock solid at up to 45mph. Somethings up if you're getting a speed wobble.

[glepore]

Price is good for their blend of components, but to me, the bike is heavy.  My old Scott addict clocks in at about 15.5 lbs.  This TanTan seems heavy to me.

The addict was always one of the lightest bikes around, the x68 is on par with a pro/expert level sl8 with a similar build. It ain't an Aethos.

[aljaz.glavac]

A bit late to the party, but still, here I am now

I've ordered x68 frame and started building it last week. x68 frame with wheeltop groupset but without chainset since I wanted to go with 52-36 chainrings. Been struggling a bit last days with BB and crankset and with breaks since this is my first build ever so yea, not stressful at all.

I will post the whole story and bike parts after I'm done, but I have a few questions:
* The bolt that is used to bleed the break caliper looks weak and I want to replace it, anyone know what type that bolt is or should I just take it out and take it with me to the shop?
* I want to buy additional derailleur hangers, does anyone know the part number or something that I can search by?

Thank you in advance!

[momento]

I will post the whole story and bike parts after I'm done, but I have a few questions:
* The bolt that is used to bleed the break caliper looks weak and I want to replace it, anyone know what type that bolt is or should I just take it out and take it with me to the shop?
* I want to buy additional derailleur hangers, does anyone know the part number or something that I can search by?

Thank you in advance!

I can’t insert the link, but if you type this on AliExpress you will find what you’re looking for.
There is a long cage version for mounting cassettes over 34 teeth, and the standard version.
The product code is this: Tarmac SL8 Bicycle Rear Gear Derailleur Hanger S206000001 Thru Axle Dorpout.
As for the caliper bolt, I’ve never seen it before. I don’t know if it’s a common spare part or if you need to ask Wheeltop.

[SkylarRnD]

Do the handlebars turn freely? I once had an issue where headset and frame rubbed, this was enough to throw the stability off. Crazy such a small amount of rubbing resists the self centering of the front wheel

Yea they turn freely. Im gonna try adjusting it again tho to see. Ill try to sand down the top cap if it rubs.

The wiggling feels like it starts around the seatpost tho and eventually starts causing the whole bike to feel very 'unplanted' is the best way to describe it.

[patliean1]

What wheels are you running? The only bike I've ever experienced speed wobbles was on my genuine SL8. Any sort of crosswind while descending above 30mph/50kph is when it happened. Later on, I determined most of the issue was I was running the 1st-gen CRW 50/60 wheels.

The SL8 is finicky. When setup properly it's more crosswind stable than other aero-ish bikes. But improper setup (wheel choice, tire size, rider weight distribution) I've found it to be worst. This is where I prefer heavier frames.

[SkylarRnD]

What wheels are you running? The only bike I've ever experienced speed wobbles was on my genuine SL8. Any sort of crosswind while descending above 30mph/50kph is when it happened. Later on, I determined most of the issue was I was running the 1st-gen CRW 50/60 wheels.

The SL8 is finicky. When setup properly it's more crosswind stable than other aero-ish bikes. But improper setup (wheel choice, tire size, rider weight distribution) I've found it to be worst. This is where I prefer heavier frames.

I was running the 9Velo CD Wide 50/58 setup tubeless with Pirelli Pzero Race TLR RS tires, 30mm wide.
I then borrowed my buddy's Lun Hyper D45s with GP5K and and latex tubes. Both setups have been unstable. Yes there's been wind both times.

[fhill]

I had/have the same issue with the bike. I doesn't feel to stable in fast and windy descents. Had a absolute nightmare descent in April where bike began wobbling at 80kph and later in June I had a not so nice descent which was due to a lot of wind. I have redone the headset since as I always had a little play in the headset. I haven't done really fast descents since, but also balancing your wheels can make a change, I think.

the bike didn't feel unstable in windy conditions when riding in the flat, there it and the wheels felt really predictable

[Kar25]

Is there anyone here who has an x68 in size 44 and could tell me what size bolts (M5-??) I need to mount brake calipers for 160mm front  and 140 or 160mm rear disc rotor?

[SkylarRnD]

I had/have the same issue with the bike. I doesn't feel to stable in fast and windy descents. Had a absolute nightmare descent in April where bike began wobbling at 80kph and later in June I had a not so nice descent which was due to a lot of wind. I have redone the headset since as I always had a little play in the headset. I haven't done really fast descents since, but also balancing your wheels can make a change, I think.

the bike didn't feel unstable in windy conditions when riding in the flat, there it and the wheels felt really predictable

I have zero play in the headset and I'm still getting that feeling. I finished up balancing the wheels(the rear was really bad and would shake the bike in the stand; doesnt do that anymore) yesterday and rode it today...its raining here so I didnt dare descend on it as its first test back. Will wait for dry weather to descend and see.
I sanded the underside of the top cap so its no longer contacting the frame. I also re-tightened the headset to be a bit looser than it previously was but still feel no play.