Merida Scultura 5000 - Ultegra 6800 Brake Calipers

This is the final piece of the Ultegra groupset! After upgrading the rest of the components on the Merida Scultura 5000 road bike to Ultegra/Dura-Ace, the brake calipers are the only remaining component that has yet to be upgraded.

Previous upgrades:
Ultegra 6800 Cassette
Dura-Ace 9000 Bottom Bracket and Chain
Ultegra 6800 Compact Crankset
Ultegra 6800 Wheelset

First, let us see what are the stock brakes on the Merida Scultura 5000. The stock brakes are Merida's own brand of brakes, Merida Pro caliper brakes. Nothing special about them, they work OK. However, the brakes tend to squeak a bit during operation. Overall, the braking performance and braking feel of the Merida road bike is not good enough for me. The braking feels rough, feels heavy and the braking performance is not ideal. I need to exert quite a lot of force on the brake levers in order to stop the bike quickly, which is poorer than the brakes on my Dahon Boardwalk.

Merida Pro caliper brakes. Weighs about 330 grams.

Here are some pictures showing the new Ultegra 6800 brake calipers! These brake calipers have been redesigned and are more powerful than the previous 6700 generation of brakes.

Ultegra 6800 brake calipers

Unboxing the brakes!

4 different length of recessed brake nuts to suit different frames

The front and rear brakes are built exactly the same, except for the length of the centre bolt.

Small and recessed axles give a more refined appearance

Rear view of the brake caliper

Another close up look at the rear of the brake caliper

Resin composite cable adjust bolt for weight savings. However, I would prefer an aluminium cable adjust bolt instead.

Notice the two adjustment bolts? The top bolt is for centering adjustment, while the bottom bolt (partially hidden) is for spring tension adjustment. For more details, read the other post on the Ultegra 6800 brake calipers.

Clearer picture showing the bottom bolt that is for spring tension adjustment

An Allen key can be used to adjust the spring tension. A lighter spring tension is usually better for lighter braking force.

Weight of the pair of Ultegra brake calipers. 11 grams heavier than the Merida brake calipers.

There are 5 components that will contribute to braking feeling and performance. The brake levers, the brake calipers, the brake cables, the brake pads and lastly the braking surface on the wheel rims. The brake levers are integrated with the Ultegra shifters, so they are already good. The rims on the Ultegra wheelset are made of aluminium, so the braking performance will definitely be much better than carbon braking surfaces.

This leaves the brake calipers, brake cables and brake pads. In order to get the best braking performance possible, all these components should be upgraded for maximum braking efficiency. The new Ultegra 6800 caliper brakes already have a cam mechanism to improve its braking power by 10% over the previous 6700 generation, so that is almost as good as it can be.

Using better brake cables will also improve the braking performance, by reducing friction and making the braking operation feel smoother. This means that more of the braking force is used to clamp the brake pads onto the rims, instead of being lost to friction.

When Dura-Ace 9000 was launched a few years ago, a new type of inner cable was also introduced to reduce cable friction. This low friction polymer cable is available for shifter inner cables and also brake inner cables. Normally, shifters already come equipped with shifter cables, and thus the Ultegra shifters are already using the polymer shifter cables for smooth and light shifting.

However, the brake cables that are used on the Merida road bike are of the standard type, which are not as good as the polymer brake inner cables. Therefore, I will upgrade the brake inner cables to the polymer type to improve the braking performance.

Complete set of Ultegra grade polymer brake inner cables and outer casings for a road bike

2 lengths of outer casings, and 2 lengths of polymer inner cable for the front and rear brakes. Special end caps with a plastic sleeve are also provided.

This is how the cables look when taken out of the cardboard packaging...

Special end caps with sleeve. This is used if the brake cable for the rear brake is routed externally. By using these end caps on the frame cable stoppers, the plastic sleeve will reduce the wear on the polymer coating of the brake inner cable.

SwissStop brake pads that are one of the best brake pads available

Now that all the components are ready, it is time to change the brake calipers, brake cables and brake pads! It is much easier to change the brake pads when the brake calipers have not been mounted on the bike, so that was changed first.

Next, the old Merida brake calipers were removed from the bike, and the new Ultegra brake calipers installed onto the bike.

Now for the tricky part, which is to change the brake inner cable and outer casing on this bike. There is no problem with the front brake cable routing, as it is very straightforward. However, the rear brake cable is routed internally through the top tube, with a full outer casing throughout.

The danger of this is that if you pull out both the inner cable and outer casing from the frame, it will be very difficult to thread the cable through the frame again, due to the small cable holes on the frame. The proper way to change the inner cable and outer casing is to ensure that at any time, either the inner cable or the outer casing must remain in the frame.

To change the brake cables, the top portion of the bar tape needs to be unwrapped.

Step 1:
Pull out the old inner cable, taking care to ensure that the old outer casing is still in the frame (both ends sticking out of the frame).

Step 2:
Thread the new inner cable through the brake cable hole on the shifter, and thread it through the old outer casing. It should poke out of the other end of the outer casing.

Inserting the brake cable through the brake cable hole on the shifter

Step 3:
Remove the old outer casing, by pulling it all the way out. Ensure that the new inner cable still runs all the way into and out of the frame.

Step 4:
Using the length of the old outer casing as a guide, cut the new outer casing to a similar length.

Step 5:
Thread the new outer casing onto the end of the new inner cable. Push it all the way through, the inner cable should be able to guide the outer casing through the frame and out smoothly.

Once that is done, you have successfully changed both the inner cable and outer casing for the rear brakes! Not too difficult if you think through the process before actually doing it.

Rear Ultegra brake mounted

Front Ultegra brake installed, along with blue coloured cable end caps.

The braking feeling and braking performance has been greatly improved after these upgrades. With the smoother brake calipers and brake inner cable, braking is now very smooth and effortless. Together with the extra grippy SwissStop brake pads, the braking power is much better than the stock condition.

In the next post, I will summarize all the upgrades that have been done to the Merida Scultura 5000, and list down the differences in performance and weight before and after the upgrades.

Caliper Brakes and Stem for the Vitesse P18-TT

In a previous post, I documented how a Dahon Vitesse P9 was converted to a Vitesse P18-TT. It is basically an 18 speed bike with road shifters and bullhorn bars, modeled after the Dahon Speed Pro TT and Vitesse P18. It combines the controls of the Speed Pro TT with the 2x9 drivetrain of the Vitesse P18.

After that upgrade, the bike worked well in all aspects, except for the brakes. The braking was unsatisfactory, due to the poor brake cable routing of the road shifter on the bullhorn bars and the extra friction contributed by the Travel Agents. There was a lot of friction within the system and braking was a chore as a lot of effort was needed to apply the brakes properly.

I have heard that some people have tried attaching a caliper brake to a Vitesse frame, but the rear caliper brake arm is far too short to reach the rims, even when extra long reach brake calipers are used. That was why I used Travel Agents with V brakes to attempt to solve this issue. However, the results were not good.

Finally, I had enough of the poor braking performance. I decided to try putting on caliper brakes on the Vitesse P18-TT, in a similar way to my own Dahon Boardwalk X20-R.

Besides the braking, the bullhorn bars also increased the reach from the flat handlebars. Usually this is good, as it allows you to stretch out more and ride in a more sporty position. However, if you are not vertically-blessed, this increased reach will make it strenuous to reach for the bullhorn bars. Therefore, I also decided to use a LitePro Stem to reduce the reach.

I shall let the pictures do the talking!

Tektro R559 Extra Long Reach calipers, with a very nice polished surface

Black LitePro Stem for 25.4mm handlebars

Right side of rear brake caliper. Using the default brake pads, the reach is slightly too short, which puts it too close to the tires.

With the special brake pads from Aican that extends the reach, the brake pad can be lowered to fit onto the rim properly.

The left side of the rear caliper does not require the special brake pad.

Most of the cases I have heard in which the rear brake calipers cannot reach the rim are on Vitesse frames. For this case, the insufficient reach was quite minor, and could be solved easily. It is possible that the mounting for the caliper brake is not consistent across different model years of Vitesse frames.

The front caliper brakes go on without much trouble. The front mounted bottle cage has been removed as it will interfere with the brake caliper arm when steering.

I tried the brakes with the stock Tektro brake pads, but the performance was quite horrible. It hardly provided any grip when the brake levers are squeezed. This is dangerous, which is why I had to solve it. Instead of getting the Koolstop brake pads which I am using on the Boardwalk, I decided to try out the SwissStop brake pads which is highly recommended.

Pricey, at almost S$40 a set from CRC

 I chose the green one as it seemed to fit my purpose and type of rims.

With the green brake pads from SwissStop, the braking performance was much improved. This has to be due to the better compound used to make the brake pads.

The other part of the upgrade is to add a stem to decrease the reach of the handlebar.

To insert the stem, one side of the bullhorn bar has to be completely cleared

Putting the stem such that the handlebar is behind the stem. This is rarely done, but seems to work fine. Fiber Grip is required to stop the stem rotating in the clamp.

Another view. Placing the stem behind the clamp theoretically has the effect of making the steering more sensitive. However, with the extra reach of the bullhorn bars, the gripping area is still in front of the clamp, and this should not be a big issue.

The brake cable housing coming out of the interrupter brake levers has to be moved as the stem interferes with proper braking function. This was solved by moving the interrupter brake levers further apart to get some clearance between the brake housing and the stem.

View of the rear brakes. With the caliper brakes, the cable routing looks neater compared to using V brakes with the Travel Agent.

Overall view of the Vitesse P18-TT

This is a successful upgrade that managed to improve the braking performance of the bike. Although it is still not very good due to the long cable housing involved, it is better than the previous version of Travel Agents and V brakes. The reach has also been reduced slightly, which makes it more comfortable for the rider.

The Dahon Boardwalk X20-R and the Vitesse P18-TT out on an extended test ride