Specialized Aethos: Tripeak Ceramic Bottom Bracket and Dura-Ace Crankset

In the previous post, I had already started the assembly of the Specialized Aethos. After assembling the fork and headset area, I continued by testing the bottom bracket.

Normally I would not install the bottom bracket first, as the internal cabling needs to be done before that. However, since this Aethos frame uses a threaded bottom bracket instead of a press fit type, it is easy to install and test to see if it fits well. It can be removed easily just by unscrewing the bottom bracket from the frame.

During this test installation, I found that the Dura-Ace R9100 bottom bracket does not spin well at all. There was a lot of resistance, which prevented the crankset from even spinning one round when I spun it by hand.

In the end I decided to give up on using the Dura-Ace bottom bracket, as the rotation feeling is just too poor. Instead, I decided to go for a smoother spinning bottom bracket, of which there are many other options.

I considered the Hambini bottom bracket, but the price of SGD 450 for a single bottom bracket is too much for me to accept. I looked for alternatives, such as the Ascent Revolution BB, but that was a bit heavy.

In the end I decided to try this Tripeak BB with ceramic bearings, which is not too expensive at around SGD 100, while being lighter than the Ascent Revolution BB. The reason I chose the ceramic version is not for smoother operation, as at such low rotation speeds, using steel or ceramic bearings make no difference. Rather, the reason is that ceramic balls are a little bit lighter than steel balls.

Tripeak bottom bracket for 68 mm English threaded frames, and for 24 or 22 mm spindles.

Specialized Aethos: Assembly Part 1 with Dura-Ace R9100 Bottom Bracket

With all the various parts of the Specialized Aethos collected, it is now ready to be assembled. Normally I would start with the assembly of the fork to the frame, and this will involve cutting the steerer tube to the required length.

Installing the super lightweight expander plug inside the Aethos fork.

Specialized Aethos: PRO Stealth Team Saddle + Camera Mount

A new saddle is needed for the Specialized Aethos, as it is an additional bike to my bike stable. Normally if I am replacing a bike, I will just transfer the saddle from the existing bike over to the new bike.

As you may already know, I am very comfortable with the PRO Stealth series of saddles, ever since I did a proper bike fitting at LOUE Bicycles. In fact, I bought many PRO Stealth saddles to replace most of my existing saddles.

The first Stealth saddle that I got was the PRO Stealth Superlight, which is found on the Focus Paralane all-weather commuting bike. Subsequently I also changed to the PRO Stealth Off-Road saddle on the Cervelo Aspero gravel bike and also the Fnhon DB11/12 folding bike.

Although there are many other saddles that are lighter than the PRO Stealth series, comfort and compatibility is more important. I would not want a superlight saddle that looks good but is not as comfortable. Therefore there was no doubt that I would get another PRO Stealth saddle for the Specialized Aethos.

Some additions to the PRO Stealth saddle lineup included the Stealth Team saddle, which is also a lightweight saddle that is different from the original Superlight model. This new model looks more appealing to me as it costs less, although it does weigh a little bit more. Check out the differences below and also at this link.

New PRO Stealth Team saddle, with an edgier appearance. This is the version with 142 mm width.

Latex and TPU Inner Tubes

In the earlier post on the Specialized Aethos, I introduced the Dura-Ace C36 wheelset, which is lighter in weight than the Dura-Ace C50 wheelset. This time, I still chose a normal clincher type of tire, which means that an inner tube is required. The Continental GP5000 tire is available in both tubeless and tubed type depending on the rider's preference.

The C36 wheelset is tubeless ready, with rim tape already installed. This setup can be used for both tubed and tubeless tires. Since I am using a tubed setup, I would need to select inner tubes for this wheelset.

Previously I have been using normal butyl inner tubes, such as those from Schwalbe. They work well, however there are now alternatives that has some advantages over normal butyl tires.

Butyl inner tubes are cheap and relatively durable, but have more rolling resistance and weigh more. The air retention is good compared to other types. It is the safe but boring option.

Latex inner tubes are a bit more expensive, and are rather fragile. The rolling resistance is very low, about the same as using a tubeless setup. The weight is about 30% less than butyl, while the folded size is about the same as butyl. Biggest disadvantage of latex inner tubes is the poor air retention, as the air pressure can drop drastically over a day. It is usually necessary to pump the tires just before going for a ride.

TPU inner tubes are relatively new, but they have the potential to become an excellent option. They are the most expensive type for now, although they are also more durable than latex tubes. Rolling resistance is also low, although not as low as latex tubes. Weight can be 1/3 that of butyl, while the folded size is reduced by half. Air retention is acceptable as it can last a few days before needing a top up.

From left to right, TPU vs Latex vs Butyl inner tubes.

TPU tube is about half the size of the other two types, which makes it ideal for packing as a spare.