Scandium 'Fastrax' Race Bike Build (1)
- Gerhard Wanninger
- May 29, 2021
- 4 min read
Updated: Jul 7
Background, 'Old' NOS KHS Alloy 7005 Frame
A few years back, I purchased a 58cm 'KHS' 7005 aluminum frame featuring carbon rear and chain stays as a NOS (New Old Stock) item, without a warranty, from a dealer. Initially, the price was low, but I negotiated it down further to NT$1,700, which is approximately US$62.00 at the time of writing.
The bike was assembled using some 9-speed mountain bike components that had previously performed well for me. Despite the carbon stays, the ride quality was somewhat harsh. I thoroughly enjoyed it, taking several tours to the South of Taiwan. I also participated in some bike challenges with it and was very pleased with the bike overall.
Unfortunately, the frame developed a cracking noise from the front chainwheel, and after looking it over roughly, I decided to buy a new bottom bracket. But even with the new part, the sound did not stop and became even more noticeable. Back home, I took a closer look and found, after further investigation with a flashlight, a thin hairline crack above the bottom bracket. Only after one additional ride, the original fine black line spread even further to the seat tube (!). From my estimation, this original cheap frame was beyond reasonable repair.
Many people listen to music through earbuds while biking. I choose not to because I prefer to feel and listen to my bike and surroundings. This allows me to detect any unusual sounds that might indicate a problem.
For instance, I once heard a consistent clicking sound from my front wheel. I stopped and found a wire tangled around the front wheel's free hub, causing this annoying noise. I noticed the earlier mentioned crack because I could hear it with each pedal stroke...
Replacement
Following the unexpected failure of my frame, I went online to find an affordable replacement. It needed to be compatible with most of the parts from the 'broken' bike. The head tube should fit my 1 1/8" carbon fork, and the bottom bracket should have threading for the commonly available BSA (or JIS). Most importantly, the frame should be lightweight and reasonably priced.
I've discovered a NOS (new old stock) Fastrax 56 cm (both center-center seat tube and c-c top tube) Scandium race bike frame for a very reasonable NT$2.500 (~US$90.00) plus shipping. I could use nearly all older parts except for a new headset and a seat post, which grew from 27.2 mm to a larger 31.6 mm diameter.
About Scandium Alloy
Upon receiving my order, the scale indicated a very respectable weight of 1,200 grams for the 56 cm frame. Scandium is a costly yet extremely light metal, known for being an effective grain refiner that can boost the yield and tensile strengths of alloys by up to 30 percent, depending on the material (pubchem.ncbi.nlm.nih.gov). This results in a lighter and stronger frame with less rigid or harsh ride qualities compared to a similar 'pure' aluminum frame without scandium.
1st Life
I assembled the frame using a carbon fork and an older Shimano Sora R3000 9-speed group, and I rode on my old, basic Shimano RS010 wheelset. The ride quality was smoother compared to the previous 7005 alloy frame with carbon stays. Despite the more aggressive riding position, I enjoyed some great tours and had a lot of fun with the bike.
Don't get me wrong, the Sora parts worked well. But fortunately or unfortunately, depending on your point of view, I've built up another 'Italian Style' bike using the latest Shimano 105 (R7000) parts. Comparing both systems, I found that the Sora's shifting felt slower and sometimes unreliable. Especially when downshifting the front derailleur uphill under pressure, some miss-shifts send me nearly flying over the bar!
While I continued riding my red 'Italian bike' I decided to transfer the Sora parts, Deda handlebar/Ritchey stem combination, and Shimano chain wheels from my Fastrax racing bike to my more leisurely mountain bike. The frame and fork of the Fastrax bike were sitting 'lonely' on Shimano wheels somewhere in a corner...
2nd Life
As soon as I hopped on my red Italian 'Peloton' bike, I felt completely at ease. Everything fit perfectly, making the ride comfortable, stable, and consequently fast. When you build your own bike, you have the freedom to select parts that match your size, color, purpose, and, crucially, your budget.
Once I've met a very young rider, a Junior High School student. He had a great bike with top-of-the-line equipment and parts. While talking, he told me that his grandfather bought it for him. I joked "that only his wheelset alone might be more expensive than my whole bike." He looked at me and asked me "what do think my wheelset cost?"
"I think around NT$40,000 (~US$ 1442.00)", I answered.
"Add another NT$10.000 (~US$360.00) and you are almost there", he said very casually.
When you have a sponsor, my homepage might be right for you...
I've noticed a significant difference between these two bikes: the red Peloton, with its 5 cm longer wheelbase, fits into the Gran Fondo category, ideal for long-distance road cycling. Meanwhile, the white/blue bike feels like a true racer; it's extremely nimble and offers a 'lively' experience when descending or taking sharp turns, demanding more active engagement from the rider.
After spending some time on the red Italian bike, I found myself missing these physical and mental challenges, especially on longer rides. After some thought, I've decided to rebuild the scandium frame with modern upgrades, particularly focusing on the shifting parts.
Ride carefully, Gerhard
A Word of Caution
Always ride with a helmet and in a way that you are in control of the bike and not the other way around. Ride responsibly and defensively, be prepared for a worst-case scenario! It is senseless to gain some seconds but spends weeks to recover in a hospital and/or at home for a stupid action! You, your body, your parents, your family, and friends will surely appreciate your precautions before, during, and after a bike ride.
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