1993 KHS ZH²B Aero Turbo
Part Diary, Part Technical Manual, Part Tips & Tricks

Back in 2010, I bought my first Aero Turbo and evenutally sold it because I felt the size was a bit small. Yesterday while looking on eBay, I found a large Aero Turbo frameset for cheap and snagged it up. This was an earlier model featureing a taller seat tube and seat stays, a little more radical looking. It also doesn't have any braze-ons for water bottle cages, so this must have been intended for shorter distance sprints and time trials. The frame also featured the earlier small san-serif logotype. One final difference I noted is that the earlier frames have the serial number stamped on the head tube while the later ones have it stamped on the bottom bracket. So on November 9, 2016, almost six years after my first one, I bought a second Aero Turbo.

1/21/2017 - The Mavic bullhorns just have too much reach and drop, so on a frame with a long top tube, I was too stretched out. Then I thought of putting on a longer stem and riser bars, but that just didn't look right on this sleek aero frameset. So I decided to get some flat bullhorns with no drop, which keeps the low and aero look but still makes it sensible to ride.

4/16/2017 - The flat bullhorns didn't have any drop, but it still had too much reach, so I finally reverted back to a traditional drop bar, which fit me better and looked better overall as well. I built this up to serve as my "nice" office bike, so it has platform pedals and threaded wheel skewers instead of the standard quick-release skewers. Narrow handlebars and no water bottle cage, all good for short urban rides.

4/30/2018 - I've been riding the bike for short sprint rides, basically what the bike was intended for, as it is aero and has no water bottle braze-ons. So I decided to make the bike more aero by putting the Spinergy wheelset on it. Since these carbon wheels are known to be fragile, this bike is more suitable for them, as my TIME Helix Equipe HM is an all around race bike. I also installed a new set of Mavic tires. The bike gained 4 oz in the process. The 40cm handlebars feel too narrow and the stem actually felt a bit short, so I'll ride it some more before I adjust anything.

8/5/2018 - I wanted to transfer most of the DA 7400 components to finish out my RB-0 project, so I put a lot of the Shimano 600 components from the RB-1 onto this Aero Turbo. I left the DA shifters on the bike and I had to use the DA front derailleur too because the 600 design would rub the rear tire.

5/1/2020 - In the midst of the COVID-19 pandemic, I sold this bike to a college freshman studying architecture at Yale.

Here are the specs:

Frame: 1993 KHS ZH²B Aero Turbo, 59cm, 130mm spacing. True Temper AVR double-butted tubing, TIG-welded. Serial Number: U30202274 (U=factory 3=1993 02=Feb). Powder coated Tiger Drylac "Anodized Silver" 38/91020. Note this frame does not have any braze-ons for a water bottle cage, suggesting this was designed for shorter all-out sprints or time trials.
Fork: KHS unicrown steel, 1" threaded. Powder coated Tiger Drylac "Anodized Silver" 38/91020.
Hubs: Shimano Dura-Ace 7402, 32h, 130mm rear spacing.
Rims: Velocity Aerohead, 32h, silver.
Tires: Mavic Yksion Power Link, folding bead, 700x23c.
Cassette: Shimano CS-HG50-8, 11-28T, Hyperglide.
Crankset: Shimano 600 Ultegra FC-6400, 172.5mm, 53 x 42 Biopace, 130/74 BCD.
Front Derailer: Shimano Dura-Ace FD-7403, braze-on.
Rear Derailer: Shimano 600 Ultegra RD-6400, grey and silver.
Lever/Shifters: Shimano Dura-Ace ST-7400, 8 speed.
Headset: Tange Levin CDS 1" threaded, chrome. After installing the Dura Ace 7410 headset with a stack height of 37.6 mm, I realized it was too tall, so I ordered this Tange with a stack height of 33.3 mm and it matched the steerer tube just fine.
Chain: KMC X8.99, 8 speed, silver.
Stem: Cinelli 1" quill with 26.4mm clamp diameter, 110mm reach, silver.
Handlebar: Cinelli Giro D'Italia, 26.4mm clamp, 40cm wide, silver.
Brakes: Shimano 600 Ultegra BR-6400 SLR, grey.
Pedals: Shimano PD-M520 SPD, black.
Seatpost: Kalloy Uno 602, 26.8mm, silver
Saddle: Cinelli Unicanitor, black.

The bike currently weighs 21lbs 9oz as shown. The frame weighs 4lbs 4oz (1,928g), the fork weighs 1lb 6oz (623g).

The following are parts that I am currently not using:

Headset: Tange 1" threaded, chrome.