This pair of Tektro brakes have served me well during these 2 years, giving me no problems at all. The wide caliper clearance means that I can still have fenders on the Boardwalk, without the fenders getting in the way of the caliper brakes. In fact there are no other caliper brakes that I know of that allows me to use fenders and caliper brakes at the same time.
Large calipers provide enough clearance for mounting fenders
I have actually been thinking of upgrading the caliper brakes for some time, but as there is no suitable replacement, it has not been possible. However, I recently had a brief discussion with a fellow folding bike rider, and I saw that his bike had only a rear fender and no front fender. His reason was that rear fenders are important to prevent a dirty seatpost and rider, but front fenders are not so important. That gave me an idea for upgrading!
This upgrade is more of an experiment than a solution to a current problem. I just wanted to try it out to see if it is possible, and how effective it is. I realised that if I removed the front fender, it actually opens up possibilities of using alternative caliper brakes!
I had known about the Elosix front brake adaptor for sometime. This is an adaptor that moves the caliper brake mounting point of the front fork downwards, to allow normal reach caliper brakes to reach the wheel rim. However, it had not been feasible or possible as the front fender was there. With the removal of the front fender, this option is now possible.
***Instead of using long reach caliper brakes, or moving the caliper downwards to reach the rim, the alternative way is to move the rim towards the brakes, by using larger 20" 451 wheels, instead of the default 20" 406 wheels. However, that is another story altogether.
Let us take a look at the Elosix front brake adaptor for Dahon/Tern bikes.
The M6 mounting bolt goes through the hole in the front fork
The holes at the bottom are for the caliper brake mounting bolt. One side has a larger hole than the other, allowing the use of recessed brake nuts.
This adaptor is inserted upwards into the hole in the middle of the front fork, and secured with the bolt through the brake hole. The M6 bolt threads through a threaded nut in the middle of the adaptor, to secure it to the walls of the front fork.
It is important to fix this adaptor really securely to the front fork, to prevent it from moving or coming loose. If it does so, the brakes will not work properly, and the adaptor may drop onto your tire and jam the front wheel! Installation not recommended for inexperienced users.
Once the new brake mounting point has been created, a standard reach caliper brake can be installed! For now, I chose a cheaper Tiagra caliper brake to try out the fit and function. Use the front brake as it has a longer mounting bolt than the rear brake.
The top bolt and nut secures the adaptor to the fork. The bottom nut is the recessed nut from the front caliper brake.
This picture should make it clear. The caliper brake mounting point has been moved downwards with the use of the adaptor.
Fits nicely! Only complaint is that the external circumference of the adaptor is round, which makes it hard for the brake caliper to sit nicely. A flat surface would have been much better.
Small clearance with my 20x1.35" Kojak tires! A 1.5" tire would not fit.
Stock Tiagra brake pads. It is actually quite a decent brake pad, with integrated convex washers for perfect brake pad alignment. However, I swapped it out because...
...I could then use my gold coloured brake pad holders, and the excellent Swissstop brake pads! I could not use the gold coloured brake pad holders last time, as I needed the extra reach from the offset Aican brake pad holders.
Looks pretty neat!
No front fenders (for the time being)
I have tested this setup for safety, and it seems to be OK. As long as the adaptor is installed properly, it will not move or drop out. The adaptor walls are pretty thick, so strength wise it should be fine.
The adaptor and brakes were also tested for flex during braking. You can try it out for yourself on your own bike, by pulling the front brake lever hard, and then pushing the bike forward and backward. Any flex in the brakes or adaptor can be seen by looking at the brake pad area. I found that there is a bit of flex, of around 1mm forward and backward. It is similar to that from the extra long reach Tektro R559 brakes, so I think it should not be an issue.
During the test rides (20+ km), it was found that front braking power is actually improved! Just by feeling, the power improvement is probably around 20%. This was not expected, but on hindsight, it is probably due to the improved leverage ratio of the shorter reach caliper brakes, and possibly less flex in the brake arms of the Tiagra brake caliper. A pleasant surprise and improvement!
However, this is not all! As was stated earlier, this was only an experiment. Now that this has been proven to work successfully, there is more to come. Watch out for the second part of this front caliper brake upgrade!