Velobuild VB-R-368 Aeroframe

[mchaggis]

Don't think XLs start shipping until the 20/10

I got my XL last week, then I did order it very early.  Dropping it in tonight to get built.  Part of me would love to do it myself but I lack the time, knowledge, tools and confidence so am outsourcing.

[Pistonbroke]

I got my XL last week, then I did order it very early.  Dropping it in tonight to get built.  Part of me would love to do it myself but I lack the time, knowledge, tools and confidence so am outsourcing.

Ooooo you lucky bugger!

Pop some photos up if and when you get a chance 

How was the tracking btw?

[aeroquest]

It looks very cool. But how fast is it really? And what about his stiffness?

[Pistonbroke]

It looks very cool. But how fast is it really? And what about his stiffness?

It'll feel like you've got an extra 50watts in your legs

[mchaggis]

Ooooo you lucky bugger!

Pop some photos up if and when you get a chance 

How was the tracking btw?

I'll see if I can get a few photos after we unwrap it and before I have to leave him to it!

Tracking was OK but not sure if it was accurate - absolutely nothing for about a week, then 2 days between showing dispatch and arriving at my office.

[Finiesta]

It looks very cool. But how fast is it really? And what about his stiffness?

In theory it shouldnt be slow because of the depth of the head tube and also headtube doesnt seem to be too wide but in reality noone will know it unless they release any cfd data or someone does real world testing comparing it to other aero bikes.

[toxin]

There are some not ideal design decisions. If you put it in a wind tunnel, it probably wouldn't score with the top western aero bikes, but it probably wouldn't be a parachute either.

[pertual]

There are some not ideal design decisions. If you put it in a wind tunnel, it probably wouldn't score with the top western aero bikes, but it probably wouldn't be a parachute either.

i feel like this frame was a good candidate for a wide fork like the quickpro ER:ONE or the new factor prototype. I agree on the testing, what looks aero does not always test well. I would have sized the downtube up a little bit to cover round bottles better, as now you have to use aero bottles if you want a nice transition. I would wager it's similar to a systemsix

[patliean1]

There are some not ideal design decisions. If you put it in a wind tunnel, it probably wouldn't score with the top western aero bikes, but it probably wouldn't be a parachute either.

Didn't both the SL8 and Evolve Cima score pretty well in the wind tunnel? This highlights your point.

I just appreciate VeloBuild doing something different enough than the one-bike-to-rule-them bandwagon. Or just producing a whole bunch of clones from Western brands, and then sending negative pushback to YouTubers for speaking on said clones in their YouTube videos.

Not that this has happened to me or anything...

[Sakizashi]

A little bit of fluids 101: Two first-order things are happening on these aero bikes.

• Deeper tubes help keep flow attached, this is particularly evident at higher yaws
• Deeper tubes create more drag through both having more area and also creating a low-pressure region on the leeward side of the foil

This means that the fastest shape is an optimization problem between the shape (incl depth) and the yaw angle. You can make a foil too deep, which slows it down. Layering in optimization for weight, and it's easy to see why the rationale for all-around race bikes exists.

Similarly, wider forks are not always faster, as you are now balancing increased flow between wider blade spacing, with the depth/shape of those blades, and should also account for wheel/tire / spoke aero issues. It's an even more complicated optimization problem.

Where does this leave the 368? I would bet that real-world testing methods, either with an aerostick or using the zero-elevation/Chung method, would show that this bike is slower than an SL8. Might be closer in a tunnel, tho.

[MALIBA]

Yesterday I carefully watched a video that showed the X-Lab. This Velobuild frame design seems very similar to the X-Lab; however, the seatpost is different, as they used the same one from the TT, and the fork is much narrower than the X-Lab's.

[JayT]

Did you know the Venge tested faster than the SL8. Quite depressing.
Maybe they'll address the pro teams demands of a new aero bike.

A little bit of fluids 101: Two first-order things are happening on these aero bikes.

• Deeper tubes help keep flow attached, this is particularly evident at higher yaws
• Deeper tubes create more drag through both having more area and also creating a low-pressure region on the leeward side of the foil

This means that the fastest shape is an optimization problem between the shape (incl depth) and the yaw angle. You can make a foil too deep, which slows it down. Layering in optimization for weight, and it's easy to see why the rationale for all-around race bikes exists.

Similarly, wider forks are not always faster, as you are now balancing increased flow between wider blade spacing, with the depth/shape of those blades, and should also account for wheel/tire / spoke aero issues. It's an even more complicated optimization problem.

Where does this leave the 368? I would bet that real-world testing methods, either with an aerostick or using the zero-elevation/Chung method, would show that this bike is slower than an SL8. Might be closer in a tunnel, tho.

[Requiem84]

I have aero testing equipment (Gibli sensor). Would be very interesting to benchmark this frame vs my Aeroad.

If anyone is in the Netherlands and has this frame, feel free to drop me a message.

[Alexlp]

AI suggested that this frame is most similar to the SIMPLON PRIDE frame https://www.simplon.com/en/Bikes/Roadbikes/Pride_b_292366

[HarryFunmaker]

AI suggested that this frame is most similar to the SIMPLON PRIDE frame https://www.simplon.com/en/Bikes/Roadbikes/Pride_b_292366

Interesting. The fork is much nicer looking on the Simplon, for sure. I think people are correct that this bike would look better with a fatter fork.