Wednesday, September 11, 2013

Journey of the Boardwalk: Part 33 - Ultegra BR-6800 Caliper Brakes

In the previous 2 parts of this upgrade, the Elosix front brake adaptor was used to mount a standard reach caliper brake to the Dahon Boardwalk. The front fender was then modified to be compatible with the new front brake configuration.

At that time, I was merely experimenting with the new front brake mounting, thus I was just using a basic Shimano Tiagra caliper brake. After it was proven that this upgrade is feasible and works well, I decided to get a better caliper brake.

The new series of road components by Shimano are the Dura-Ace 9000 and Ultegra 6800 series. Amongst the new components are newly designed caliper brakes, designed to be even more powerful than the previous Dura-Ace 7900 and Ultegra 6700 versions. Without question, the brakes that I decided to get was the Ultegra 6800 brakes, as the colour matches the rest of the components on my bike (Ultegra 6700/6770).

A quick comparison of the Ultegra 6700 vs Ultegra 6800 caliper brakes:

Ultegra 6700 brakes

Ultegra 6800 brakes

From the pictures above, you can see that the new Ultegra 6800 brakes has an additional section on the top brake arch. This is due to the new cam mechanism in the brakes, designed to improve braking power.

Both the brakes are of dual pivot design, but the pivot locations are different. The 6700 brakes has one of the pivots on the centre mounting bolt itself, while the 6800 is a symmetrical dual pivot design, with the 2 pivots at both sides of the brake caliper. Again, this is designed to improve braking power.

Let us now take a closer look at the brake new Ultegra 6800 brakes which I bought! I only bought the front brake (with the longer mounting bolt) as I can only change the front brake. The rear brake will remain as the Tektro R559 Extra Long Reach caliper brakes.

Beautiful packaging for the Ultegra 6800 brakes

Possible to buy just a single brake (instead of a pair) online

 Same colour scheme as the Ultegra 6700 series! 
Matches the rest of my Ultegra 6700/6770 components.

Long mounting bolt for secure mounting to the Elosix front brake adaptor

Comes with an additional 4 recessed brake nuts of different lengths, to suit different frames.

 Centering adjustment bolt on top, for adjusting the pad clearance for one side.
Spring tension adjustment bolt in the middle, to increase or decrease the spring tension. 
 The roller cam mechanism as seen hidden between the 2 brake arms.

The main features of this new brake design is the improved symmetrical dual pivot design, which puts both the pivots at the sides. The closer the pivot to the brake shoe, the higher the leverage and that improves the braking power.

Also, the roller cam mechanism uses the motion of one brake arm to push the other brake arm, increasing the force and therefore also increasing the braking power.

Tight clearance between the brakes and the 20x1.35" Kojak tires. Even smaller clearance compared to the Tiagra caliper brakes. Note the locations of the dual pivots.

Tire clearance on the previous Tiagra brakes.Slightly more than the Ultegra 6800 brakes. Note that there is no independent pivot on the left side of the picture.

 Used the default Ultegra 6800 brake pad holder, but changed to the SwissStop brake pads. Could not get proper pad alignment with the gold coloured brake pad holders.
 
Just for comparison. Similar reach for the Tiagra and Ultegra brakes.

The Tiagra brake's cable adjust bolt is at a much higher position than the Ultegra cable adjust bolt. The centering alignment bolt is also located at different positions.

Installed and aligned properly on the front fork of the Dahon Boardwalk

Overall view of the new Ultegra 6800 front caliper brakes!

After a couple of test rides today (20+ km in total), the new front brake is performing flawlessly. Not only is the braking action light (due to lighter brake return spring and roller bearings in the brakes), the brakes feel super smooth too. There is noticeably less flex in the brake arms (compared to Tektro R559) when the brake lever is fully depressed. This gives a very solid and firm feeling when the brake pads contact the rim.

As for the braking power, it feels slightly better than the Tiagra caliper brakes, but without any measurable data, I cannot confirm it. However, it is a great improvement over the previous Tektro R559 brakes.

I am really satisfied with this front brake upgrade. Although I was not able to upgrade the rear brakes, it is better to upgrade one than none at all. After all, it is definitely advantageous to have one good brake and one average brake, rather than just 2 average brakes.

If you are thinking of buying new road caliper brakes, you may want to consider getting the newer Dura-Ace 9000 or Ultegra 6800 brakes for the improved performance.

Info: Ultegra 6800 brakes are available at Hup Leong for $205 a pair (dated 4 Sep 2013).

19 comments:

  1. Hi,

    The Shimano Ultegra 6800 won't be able to fit 1.75" tyres for both the rear and front? Currently using Dahon Vector P9.

    ReplyDelete
    Replies
    1. No the wider 1.75" tires won't fit. As you can see from my pictures, the 1.35" Kojaks only barely fit.

      Delete
  2. Thanks for the reply Steve,

    My wild guess is to keep using V brakes? What's your opinion on Avid Single Digit 7 Brakes or do you have any other recommendations?

    Thanks!

    ReplyDelete
    Replies
    1. V brakes will work fine. Don't change to caliper brakes unless you are using road shifters.

      The Avid SD7 is a pretty good choice, inexpensive with good performance. Alternatively you can look for Shimano V brakes such as Deore, LX or XT Trekking. BR-M590, BR-T610, BR-T670 or BR-T780.

      Delete
  3. im running conti gp 4000s 25mm on my road bike would this also be a clearance issue?
    cheers

    ReplyDelete
    Replies
    1. if your frame is designed properly there should be sufficient clearance. The Kojak tires that I am using is 35mm wide.

      Delete
  4. Hi Steve,

    Can I just check if the colour scheme for the 6800 brakes is indeed darker than the 6700 ones?

    The pictures make it look like it's black (if not almost black), which is a lot darker than the space grey of the 6700 series.

    ReplyDelete
    Replies
    1. Ultegra 6700 comes in 2 colours, silver and glossy grey. The new 6800 colour scheme looks the same as the glossy grey of 6700. The appearance of the 6700 glossy grey matches well with the 6800 colour scheme as they look the same.

      Delete
  5. how to determine if the drop of the caliper brakes is enough? i'm planning to get shimano 105 5800 (with drop of 49mm) for my dahon speed falco. please advise.

    ReplyDelete
    Replies
    1. Measure the vertical distance from the centre of the caliper brake mounting hole to the centre of the rim braking surface, this would be the drop required.

      Delete
  6. Hi Steve,

    I'm currently using the same Dahon Mu Ex frame that you bought from TB and just installed the Ultegra 6800 STI shifters. Problem is, my V-brakes are very closed to the rim that they tend to rub esp when wet.... is it advisable to widen the gap between the rim and brake or is caliper the way to go for these drop bar shifters?

    If yes, is there a way to even install the caliper to this frame? Thanks

    ReplyDelete
    Replies
    1. Road shifters are designed to be used with caliper brakes. Using them with V brakes will cause the issues that you have encountered. Increasing the gap will make the brake lever bottom out before you can apply sufficient braking force.

      Are you using bar end shifters or STI shifters? I thought you previously managed to get the 11 speed bar end shifters to work with the 5700 FD.

      Delete
    2. STI shifters. In the end returned the bar end shifters for the Ultegra STI because there was no way to clamp the TT bar firm enough (even when the bolts are at 11 Nm) and the bar just kept sagging esp when going over humps. Changing to OS dropbar solved that problem totally.

      And yes, we managed to get the 5700 FD to work with the 6800 shifters w/o issues.

      So question is, how viable are caliper brakes on the Dahon Mu Ex frame and whether they can be installed w/o much fuss?

      Delete
    3. You will need long reach Tektro R559 caliper brakes. Not sure if the rear can fit as the caliper arms may hit the seat stays. Have to try to know.

      Or, change to 451 wheels and can probably use standard reach caliper brakes.

      Delete
    4. ok thanks Steve :)

      I'm using the 451 Wheelset, so I guess either Shimano 5800 or 6800 would be good. Any noticeable difference between 105 and Ultegra performance? More inclinded to the 105 since it's matching black to the Dahon Mu Ex frame ;)

      Delete
    5. The black 5800 would match better, but the 6800 overall appearance is nicer. Your choice.
      http://handsonbike.blogspot.sg/2015/01/difference-between-ultegra-6800-and.html

      Delete
  7. Hi Steve, currently im using ultegra 6800 brake on roadbike,intend to convert dropbar to flatbar any recommend model of shifter and brake lever to choose?

    ReplyDelete
    Replies
    1. This one is easy. Get the SL-RS700 2x11 speed road flat handlebar shifters. As for the brake levers, you can use BL-4700 or BL-R780.

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    2. Thank you for your advice Steve.

      Delete