1 x 12 Sram TT Setup

[mauwth]

Hi everyone,

Since someone was referring to a VeloBuild VB-TT-023 here, here's my build. It is a weapon. Very fast and very sexy looking.

The only thing was that the original cockpit wasn't working well for me. Too low, too close to my body and too narrow.

So I customized the cockpit quite a bit:

#1: I cut a custom aero bar base plate from a 4 mm thick carbon sheet in order to bring the underarm rest pads more outward and further forward than the original base plate would allow.

#2: This also allowed me to add a QuadLock mount for my phone, so that I have my data right between my arms.

#3: I 3D-printed two one-piece 12 cm tall spacers. In order to give them more stability, I replaced the long M5 bolts with thicker, extra-long M6 bolts, which meant I had to drill the holes in the handlebars a tiny bit wider.

#4: I also 3D-printed a little box that is attached underneath the aero bar base plate and which can slide in two energy gels while I’m riding.

#5: I ended up not attaching the water bottle to the seat post. I attached it to the down tube. Looked better and way easier to grab the bottle while riding.

Photos (incl. Adobe Illustrator drawing of the custom carbon aero bar base plate I built):
https://drive.google.com/drive/folders/1mE7LtKe21CTyAYtPoBpYAIpCF4da8K-i?usp=sharing

Feedback appreciated!

Have a good one!
Martin

[Da11as]

Hi everyone,

Since someone was referring to a VeloBuild VB-TT-023 here, here's my build. It is a weapon. Very fast and very sexy looking.

The only thing was that the original cockpit wasn't working well for me. Too low, too close to my body and too narrow.

So I customized the cockpit quite a bit:

#1: I cut a custom aero bar base plate from a 4 mm thick carbon sheet in order to bring the underarm rest pads more outward and further forward than the original base plate would allow.

#2: This also allowed me to add a QuadLock mount for my phone, so that I have my data right between my arms.

#3: I 3D-printed two one-piece 12 cm tall spacers. In order to give them more stability, I replaced the long M5 bolts with thicker, extra-long M6 bolts, which meant I had to drill the holes in the handlebars a tiny bit wider.

#4: I also 3D-printed a little box that is attached underneath the aero bar base plate and which can slide in two energy gels while I’m riding.

#5: I ended up not attaching the water bottle to the seat post. I attached it to the down tube. Looked better and way easier to grab the bottle while riding.

Photos (incl. Adobe Illustrator drawing of the custom carbon aero bar base plate I built):
https://drive.google.com/drive/folders/1mE7LtKe21CTyAYtPoBpYAIpCF4da8K-i?usp=sharing

Feedback appreciated!

Have a good one!
Martin

Hey, like the build in general, but I have doubts regarding the cockpit safety. Considering current setup, I assume you have most of your weight on the aero bar pads which are shifted way beyond spacers' point of higher rigidity which may eventually result in a catastrophic failure of: a) base bar; b) aero bar. Depending on where your elbows are I would install longer stem or buy longer aero bar extensions.
Additional note on the feed box: If it has the same shape as your upper plate adapter and you want to keep it there I would change the shape for a more aero shape or narrower one (basically, change the position of the 'shelves' from horizontal to vertical). Maybe I am wrong but from these pictures it looks like the box has aerodynamics of a brick

[Hmpf]

That Looks really Clean, good Job.

Whats the model of Aero bottle?

[mauwth]

Hey, like the build in general, but I have doubts regarding the cockpit safety. Considering current setup, I assume you have most of your weight on the aero bar pads which are shifted way beyond spacers' point of higher rigidity which may eventually result in a catastrophic failure of: a) base bar; b) aero bar. Depending on where your elbows are I would install longer stem or buy longer aero bar extensions.
Additional note on the feed box: If it has the same shape as your upper plate adapter and you want to keep it there I would change the shape for a more aero shape or narrower one (basically, change the position of the 'shelves' from horizontal to vertical). Maybe I am wrong but from these pictures it looks like the box has aerodynamics of a brick

Hi! Excellent points, but obviously all things I considered and thought about (this is - by far - not my first custom build). Let me explain ...

#1 Custom Base Plate

There are three main factors determining the stress on that plate. 1) your own body weight and how much of it will rest on it, 2) the strength with which it is attached to the rest of the bike and 3) where you will be riding this bike. I thought about all three.

First of all: this base plate shifts the underarm rest pads only 1 cm further forward than the original VeloBuild base plate would have allowed anyway. So we are not talking huge shifts here.

But even leaving this aside, the 4 mm carbon sheet I used is stronger, stiffer and at the same time lighter than what VeloBuild supplied.

Also keep in mind that by 3D-printing my own spacers (from the hardest 3D-printable plastic available, by the way) I raised the height by 70(!!) mm over what the spacers supplied by VeloBuild enabled me to do. That in turn means that your upper body is also much further up, which in turn means that a lot less of its weight rests on the pads.

I also do a lot of TT-related body core exercises, so that I don't actually rest with a lot of weight on it, as compared to the average cyclist not doing any strength training.

Further, the one-piece spacers are vertically and horizontally stiffer than the individual pieces VeloBuild supplied, which you have to stack on top of each other. They are solid inside.

More: they have much thicker M6 bolts going through them, then the M5s that VeloBuild supplied. And I didn't go cheap with these bolts. These are high-strength steel bolts that were $10 a piece. Not cheap at all.

Lastly: this bike will only be ridden on flat and excellently paved asphalt roads where I live. There are literally no potholes to speak of. But even if there were, I have 100% confidence it could handle them repeatedly.

#2: Feed Box

You probably can't fully judge this from the photos, but the gels are actually inserted parallel to the ground, so that the box' long side is in line with air flow. And: it has an air foil shape, also in line with the airflow. And no: it's not the same shape as the base plate, it's much narrower. The pictures from the side of the bike just leave the impression that it's bulky and boxy. But it's not.

So I thought about this as well.

I did actually read a few reports on handlebar feed boxes and/or hydration system and my custom box is smaller and more aerodynamically shaped than any of the hydration systems you will find on the market.

Lastly (and of course I can't fully confirm this without using a wind tunnel): but it could actually be argued that it helps separating the air in front of the main wind obstacle: you body and waist. Similar to what a water bottle stuck under your jersey in front of your chest would do. The UCI banned this, but tests have shown that it makes a very significant difference to split the wind before it hits your body.

Hope that clarifies things!

Best,
Martin

[mauwth]

That Looks really Clean, good Job.

Whats the model of Aero bottle?

Hi, thanks! This is an aero bottles that normally comes with the Orbea Ordu TT bikes. Same goes for the tool box at the bottom. Also from the Orbea Ordu TT bike. I had to cut a bit of its plastic parts off to get it to fit onto the down tube of this frame. You can order the cage/bottle as well the tool box directly via Orbea's website. Best, Martin

[ejump0]

Hi everyone,

Since someone was referring to a VeloBuild VB-TT-023 here, here's my build. It is a weapon. Very fast and very sexy looking.

The only thing was that the original cockpit wasn't working well for me. Too low, too close to my body and too narrow.

So I customized the cockpit quite a bit:

#1: I cut a custom aero bar base plate from a 4 mm thick carbon sheet in order to bring the underarm rest pads more outward and further forward than the original base plate would allow.

#2: This also allowed me to add a QuadLock mount for my phone, so that I have my data right between my arms.

#3: I 3D-printed two one-piece 12 cm tall spacers. In order to give them more stability, I replaced the long M5 bolts with thicker, extra-long M6 bolts, which meant I had to drill the holes in the handlebars a tiny bit wider.

#4: I also 3D-printed a little box that is attached underneath the aero bar base plate and which can slide in two energy gels while I’m riding.

#5: I ended up not attaching the water bottle to the seat post. I attached it to the down tube. Looked better and way easier to grab the bottle while riding.

Photos (incl. Adobe Illustrator drawing of the custom carbon aero bar base plate I built):
https://drive.google.com/drive/folders/1mE7LtKe21CTyAYtPoBpYAIpCF4da8K-i?usp=sharing

Feedback appreciated!

Have a good one!
Martin

/i still havent finalized the location for sram blips on my basebar.

your basebar reach is so long. are you customing some kind of extender before the brake level?

my tt912 basebar is flipped downside up whic i like, but longer reach would make it better

[estingo]

I agree, however i chose 50 just because i played it safe on my first tri race. 50t was the largest chainring i could find 2 weeks into the race, i considered the 2.5k elevation of the course im headed to.

I also run a 1x and have the 52t, when I do more elevation I also change it to the 50t; however, I have a 10-28 cassette and no TT bike. It works fine for me and I'm in the middle of the cassette with this.
Coming weekend I'm going to some hills and therefore I change now to 2x 50-36 10-33 but when I'm back I'll do the 1x 52t 10-28 again, it's so flat here that it works just fine. For a race, I can imagine that you are doubting to go for 50t or 52t if there is an elevation of 2.5 km. Larger is possible, but then you need to be strong; it needs to be most of the time flat, downhill or backwind. TT bike and the position could potentially handle larger teeth, but you also ned to feel comfortable with it. Because it's difficult to compare yourself to the pros, they run like 64t or even bigger nowadays (https://www.instagram.com/p/DJeaVefIen6/?utm_source=ig_web_copy_link&igsh=MzRlODBiNWFlZA==).

Just my 2 cent and experience

[mauwth]

/i still havent finalized the location for sram blips on my basebar.

your basebar reach is so long. are you customing some kind of extender before the brake level?

my tt912 basebar is flipped downside up whic i like, but longer reach would make it better

Haha, they are so long simply because I haven't shortened them yet. But will do so soon. They came in that length.

[sandwich]

I have this setup on my hongfu.  I run blips on the base bars and skis, and a “normal” force RD.  I run a 1x12 on my road bike and have liked it there, so I decided to go with it on my TT bike as well.  The main course that I ride, and all of the roads out here, are very hilly with minimal extended climbing.  My older SRAM s80 wheels are difficult to find parts for, so I ended up with a campy 12 speed cluster for an 11-29.  I run a 48t pass quest front ring on a shimano 105 crankset.  I know that 48t isn’t bro approved, but when riding my loop I find that I’m using the entire cassette and spending most of my time in the lower 1/3 of the cassette which has better alignment with the chainring.

I suppose I could have gone for the fatter cassette with a bigger low gear, but was limited by free hub compatibility (10 speed or campy is what I had access to) and didn’t want the large gear jumps.  So now I have a wildly bastardized setup with quick shifts and no cable routing!