Friday, January 8, 2016

Wheelsport Fantasy 2x10 Speed: Part 5 - Flat Bar to Drop Bar Conversion

Part 1: Original Bike Components
Part 2: Bike Disassembly and Component Weight
Part 3: Installation of New Components
Part 4: Final Assembly and Comparison


Remember the Wheelsport Fantasy 2x10 Speed flat handlebar mini velo that I built for my friend? It was previously using mostly Shimano 105 5700 components transferred over from my Dahon MuEX. It worked very well and it shifted much better than the stock 1x9 speed drivetrain that came stock with the bike.

However, it was unfortunate that the bike crashed and was damaged. Luckily the rider was OK, but there was some significant damage to a few of the components. At the same time, me and my friend thought that it would be a good idea to convert the Wheelsport Fantasy flat handlebar mini velo to a drop bar set up. This would enable the rider to get down into a more aerodynamic position for more speed.

Therefore, the plan is to repair the damage on the bike, and also convert it from a flat handlebar to a drop bar set up at the same time! First, let's take a look at the damage and see how it can be fixed.

The bike crashed on the right side, which meant that the damage was all on the right side of the bike. Other than the non-critical scratches on the pedal and the end of the handlebar grip, the most critical damage was found at the rear derailleur.

As seen below, there was great impact on the rear derailleur, causing lots of scratches, and most critically, a bent rear derailleur hanger. The rear derailleur itself would probably still work fine despite the scratches, but the bent RD hanger needs to be fixed.

Some deep scratches on the 105 5700 rear derailleur, but probably will not affect the function.

However, the RD hanger was quite badly bent, causing the gear shifting to be all wonky and not fixable. 

The RD hanger is usually designed such that it is soft and will bend during impact, so that the frame itself does not get damaged. A replacement of the RD hanger and maybe the rear derailleur (depending on extent of damage) will be able to fix this issue. As this Wheelsport Fantasy mini velo frame was from MyBikeShop, I went back there to get a replacement RD hanger for this frame. Luckily, they had it in stock and so I could quickly get a replacement.

Replacement RD hanger for the Wheelsport Fantasy mini velo frame!

Comparing the old and new RD hanger side by side, the damage is quite obvious.

With the RD hanger issue fixed, the next step is to gather all the components for converting to a drop bar set up. Normally, converting from a flat handlebar to a drop bar set up is relatively easy. All it takes is a drop bar, a road shifter for the drop bar, and some re-installation of the inner cables.

As the bike already has a 10 speed Shimano 105 5700 RD and a 5700 FD, along with a 10 speed chain and cassette, all it takes is a change of shifters. Compatible 10 speed road shifters would be either Dura-Ace 7900/Ultegra 6700/105 5700 or Tiagra 4600 shifters.

However, these are the previous generation of shifters, which are not as good as the latest generation of shifters (Dura-Ace 9000/Ultegra 6800/105 5800/Tiagra 4700). I would prefer to upgrade to the newest generation of road shifters if possible.

The problem is, the latest Dura-Ace, Ultegra and 105 are all 11 speed groupsets, which requires a totally new drivetrain. Using these 11 speed shifters would require a change of the RD, FD, chain, cassette and maybe the crankset. Also, I am limited by the rear hub on the wheelset, which can only support up to 10 speeds. Going to 11 speeds would require a new wheelset which is a costly investment.

The good news is, the latest Tiagra 4700 road shifters are still 10 speed. The bad news is, the cable pitch for the new Tiagra 4700 series is different from the previous Tiagra 4600 series. In other words, it is still 10 speed, but the RD, FD and shifters operate on a different cable pitch.

What does all these mean? The implication is that the 10 speed cassette, chain and crankset are still perfectly compatible across the old and new 10 speed drivetrains. There is no need to change out these components if I am changing from the current 105 5700 series to the new Tiagra 4700 series.

What I do need is the new Tiagra 4700 road shifters, and the new generation of RD and FD. All other drivetrain components on the bike can remain the same.


First of all, a drop bar is required. This FSA handlebar is either from the Merida Scultura 5000 or the Dahon Boardwalk, I can't remember which bike it came from.

Next, the new Tiagra 4700 2x10 speed road shifters! Construction is based on the latest generation of 11 speed shifters, with lighter shifting and better ergonomics.

Weighs 492 grams per pair, quite decent weight, although it is quite far off the 365 grams of the Dura-Ace 9000 shifters.

The ideal rear derailleur and front derailleur to go with these Tiagra 4700 road shifters would be the Tiagra 4700 RD and FD. However, these are currently (Sep 2015) quite difficult to get hold of as they have just been launched to the market recently, and are only found on OEM bikes for now. As such, I decided to use the 105 5800 RD and FD instead. These are actually 11 speed RD and FD, but I figured that since the construction of these components are similar to the Tiagra 4700 components, they should also work with the Tiagra 4700 shifters, although they may not work perfectly. Besides, the black colour of the 105 5800 RD and FD would better match the black Wheelsport Fantasy frame.

Shimano 105 5800 Double FD, for 11 speed drivetrains. Brazed on type. Similar in design to the higher end Ultegra and Dura-Ace FD.

Weighs 89 grams, which is actually similar in weight to the Ultegra FD.

Shimano 105 5800 11 Speed RD, short cage version. Also similar in construction to Ultegra and Dura-Ace.

Weighs 226 grams, a bit more than the Ultegra RD.

Polymer coated shifter inner cables on the left, normal stainless steel brake cables on the right.

Installing the shifter inner cable on these new shifters require a special nose cap on the shifter to prevent unwanted wear on the inner cable.

Shifters and drop bar installed on the bike. Stem has been lowered slightly for a more sporty riding posture.

After installing the shifters, the next step is to install the new RD and FD. Nothing special here, just remove the old RD and FD and install the new ones. After that, the cabling and the adjustment of the RD and FD can be done.

All inner cables and outer casings installed, including those for the brakes!

FD-5800 installed! Bolted on directly to the FD hanger.

Tucking in the inner cable for the FD through the FD hanger, to prevent the cable from touching the leg during pedaling.

RD-5800 installed! New RD on new RD hanger.

The installation is almost complete! Adjustment of the RD and FD went without any issues, it seems OK to use the 11 speed RD and FD with these 10 speed road shifters. The only thing left is to wrap the bar tape, and to compare it with the other Wheelsport Fantasy Ultegra Di2 mini velo that I have! To be continued in the next part...

5 comments:

  1. I like this bike, Really very powerful and light weight...

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  2. What tools are use for this changes? I'm planning to change out for my Java CL 16 too.

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    Replies
    1. No special tools, just the usual Allen key set and screwdriver. Cable cutter for cutting inner cable and outer casing.

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    2. Btw, you physically cut the stem to lower it?

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    3. No stem cutting. You can't cut the stem anyway. Unless you are referring to the handlepost.

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