Here is the second part of this bike build, the Fnhon Ultegra Di2 12 speed drop bar folding bike. As explained in the earlier posts, there are a few problems that had to be solved for this build to be possible.
3) Narrow wide chain ring that is compatible to Shimano 12 speed chain AND Shimano 4 arm road crankset.
Here is the completed build!
Ultegra Di2 shifters ST-R8170 with good ergonomics.
Using the same outward folding handlepost from the Dahon MuSP. Hydraulic hoses neatly routed.
Controltech stem to allow the 31.8 mm diameter drop bar to be mounted to the handlepost.
During the initial setup, I made the chain too short, because I thought that the shorter Ultegra R8000 cage would not be able to handle too much chain slack. However, I realized that this was not the case. I could still lengthen the chain without causing the chain to go slack in the smallest sprocket.
The good thing about running a front single drivetrain is that you have more flexibility to adjust your chain length, as the rear derailleur cage capacity is more than what is required for a cassette without a double chain ring.
Therefore, I decided to add back some of the links to reduce the chain tension. A reduced chain tension would give a smooth pedaling feel, but also higher chance of chain slapping when travelling over bumpy terrain.
Adding back some of the links to the Shimano M9100 12 speed chain, using a KMC 12 speed Missing Link.
At the largest 34T sprocket, the cage is not overstretched. Previously, with 6 lesser chain links, it was under high tension.
Comfortable clearance between the derailleur cage and the spokes and rim.
At the smallest 11T sprocket, with a good amount of chain tension.
There is still quite a bit of distance between the stopper surfaces, which means that this derailleur cage can handle the 11-34T cassette with a big margin.
Picture of the completed bike, with Ultegra Di2 1x12 speed drop bar setup.
The other side, showing the brake rotors and brake calipers.
Bike half folded for storage at home. This has the smallest footprint compared to the full fold that has the handlepost folded down.
Bike fully folded for transport in a car. The handlepost folds outwards, as seen on the Dahon MuSP.
Top view of the fully folded bike, with the handlebar sticking out a lot.
This fully folded setup takes up more floor space compared to the half folded setup.
The 3-way swap project is now complete! The other 2 bikes are the Birdy AXS 12 speed and the Dahon MuSP 1x9 Speed Flat Handlebar.
Full specifications of the Fnhon Ultegra Di2 12 speed drop bar folding bike.
Compared to a full sized carbon road bike with similar component specifications, the weight of this folding bike is at least 2 kg more. This can't be helped when this Fnhon aluminium frameset (frame + fork + handlepost) already weighs over 3.5 kg.
Still, a weight of 9.2 kg for an aluminium drop bar folding bike is pretty decent. Especially since this is a fully hydraulic brake system, as a hydraulic brake system adds about 0.5 kg over a mechanical brake system.
Here's how it compares to some other drop bar small wheel bikes. All weights are without pedals and kickstand.
Folding Bikes
Tern Verge X18 (mechanical): 10.4 kg
Mini Velo
In the next post, I will compare the geometry of this Fnhon drop bar folding bike with a road bike, to highlight the differences.
No comments:
Post a Comment
Every comment is moderated before publishing due to spam bots. If you don't see your comment yet, it is likely that it is currently being reviewed. Thank you for your patience!