Installation troubles… all bundled together
A fork for the “LOTUS SPORT110” that I had as a spare
1-inch, oversized, threaded headset specs—quite the puzzle…
Turns out the bearing press fit on the fork side was machined to oversized for some reason.
If I had headset parts that matched 1-inch on the frame side and oversized on the fork side, it would work, but I couldn’t find any…
In the end, I turned the fit on a lathe.
Plus the length wasn’t enough, so I wanted to extend it, but I didn’t have material…
Speaking of material, there was also the legendary Togashi frame from Togashi Engineering back in the day ★
Looking at the material chart, SCM430 in 1-inch has so many different wall thicknesses…
I didn’t need 2 meters, so I cut up the fork I had on hand.
Press-fitting and welding would be the safe approach, but since it’s mine, I went with generous root opening and made do.
After that, I used V-blocks and a hydraulic press, corrected everything with a dial gauge, and finally got it mounted.
Making the track ends.
The dummy came out perfect on the first try, so I’ll do the real one another time. Honestly, it’s a bit thin…
The relationship between the brake caliper position and the wheel position turned out to be surprisingly tricky…
At least it fit, and I’m glad.
Last night, inspiration struck…
The thread pitch on a freewheel cassette is the same as on a track cog.
I thought the distance from the wheel center to the thread pitch would also be the same… but they’re completely different…
Freewheel cassette = threaded section with minimal protrusion (small offset)
Track = threaded section with more protrusion (large offset)
When you think about it, that makes sense…
As the number of cogs increases, the cassette gets thicker, so you have to push it inward—that’s essential.
So… what to do?
I went with just fitting the freewheel cassette in for now. The 6-speed feels surprisingly good ★
The 8-speed Reyna I had on hand felt a bit tight.
If I had time, I could make an adapter that goes from freewheel cassette to track cog, which would work fine, so this is temporary for now.
The brake area is done—cleaned and adjusted the tension on the ZIPP-specific coil spring ★
The rear is bottom-pull mounted. To avoid interference, it has to be center-pull.
No replacement push pin, so I’m holding it with tape for now ★
The outside is dry carbon, but inside it’s just an aluminum plate—a heavy, heavy caliper.
This part went on smoothly.
Whether the singlespeed crank is offset quite far inward or because it’s an external-bearing bottom bracket, there are lots of new things I’m encountering.
I couldn’t warm up to that anchor-ring-looking thing for adjusting handlebar height on the headset…
In the end, I machined down the 75 and made it a monoblock that expands to the stem outer diameter.
At least now it looks like I can use it for commuting, so I’m happy.
Next year, I’d like to bring the “LOTUS SPORT110” back to life as a singlespeed if I can.
It’s turned into another hard-to-ride, unusable bike that I can’t even stop at a convenience store on.
I’m getting a bit fed up with building bicycles when I’m not used to it.
That’s all! See ya
