Monday, 16 July 2012

The Build Part IV: It's a wrap!

This is the final post in what turned out to be a four-part series.  In the last part I got the chain fitted, all that remained was for me to check the position of the brifters and handle bars before taping up and make those last minute adjustments to the gears that are inevitably necessary.

I did have one little niggle with the front derailleur adjustment before I could close out the build.  When I first connected the cable to the front derailleur I had an issue with a bit of poor alignment in the lever body.  The outer body of the lever has a hole through which you feed the cable for the gears, this is supposed to line up with a hole on the inner body but mine were misaligned and the gear-cable end caught at the interface.  I pulled the cable tight from the other side and didn't notice until I came to adjust the front derailleur - it was clear something was wrong but it took some searching to identify this as the problem.

With the cables connected and adjusted and the rain stopping I took the bike for a quick spin around the block to check I was happy with the position of the levers and the tilt of the bar.  Sadly, with a strong wind blowing up the nearest gradient it was impossible to really get out of the saddle to get the feel for the position.  Also, the rain only stopped for about 20 minutes before the weather closed in so I did a few tweaks and then had to run inside before I got drenched.

Still, impatient to finish the job I turned to the last task: taping up the bars.  The wintry weather had given me plenty of time to read up on this task.  Here are my three main picks for a description of how to do this job...

Installing Handlebar Tape - Sheldon Brown

This one had to be top of my list because, on a Cinelli frame with a Cinelli bar it simply has to be Cinelli cork handlebar tape to finish the job. The author even describes himself as "Sheldon 'corker' Brown" here so he is clearly aiming the article at people like me. Sadly, the article is incomplete. It is possible to get a few glimpses of his approach though.

The key to a reliable taping job is tension. As you wind the tape onto the bars, you should hold it under constant tension, never letting it go slack. The amount of tension should be quite considerable, enough that you might actually worry about breaking the tape

and on the important issue of winding direction:

Generally, handlebar tape should be wound on starting at the ends of the bars and winding toward the middle....

...I generally start from the underside of the bar, with the tape feeding outwards. You can do it the other way too, but make sure you follow the same pattern on both sides.

Handlebar Tape Installation (drop bar) -

In general, you can do a lot worse than following ParkTool's advice on most matters I find. Perhaps the most accurate advice on the internet...

Handlebar wrapping is a skill that takes practice and patience.

This bike build introduced to me to a lot of new tools and components but in most cases using the right tool, following the instructions and using the correct tension when tightening fasteners means that no particular skill was required. Sure, it took me much longer than an experienced bike mechanic but the results have been similar up to this point.

On the issue of winding direction ParkTool's blog is more definitive:

Looking from the rider's point of view (from the back of the bike) wrap each side the tape rotates inward from the top. In other words, wrap the right bar counter-clockwise and the left bar clockwise.

How To - Handlebar tape - Sprinta Della Casa

My final pick is the more quirky Sprinta Della Casa. This article goes into a little more detail. It's less emphatic about the correct winding direction:

I wrap from the inside, over the bar. If you do it the other way it's up to you, but I've found the "over" direction works well.

This is the opposite of Sheldon Brown's preference and ParkTool's recommendation which suggests to me that it probably doesn't matter that much. I like this article for the conversational style and the number of pictures.

In conclusion, the golden rules seem to be:

  1. Clean hands
  2. Tools within easy reach (so you don't have to let go)
  3. Wind from the bar end towards the centre

My first attempt

Sadly, my first attempt was not very successful. It is a long time since I wrapped my bars and I'd never used the Cinelli tape before. I was worried about breaking it and didn't pull hard enough to get a snug fit. I was also using the Gel variant of the Cinelli tape which has two adhesive stripes rather than a single central strip. This reduced the traction on the bar during the job and meant that a couple of times, where I'd broken golden rule number 2, the tape started to unwind.

After the first half of the bar was done I had more tape left over than I expected - I could have increased the overlap, particularly around the tight parts of the bend. I did the second half of the bar better and when I finished the job the tape looked fine but I could have usefully gone back and re-wrapped that first bar with hindsight.

The result, after 500 miles the tape was already coming loose. After 750 miles I gave up and rewrapped. That gave me an opportunity to change the colour of the tape too (on reflection, the white looks better than the blue).

In summary, I'd add a fourth golden rule to the three above. If this is your first time with a particular type of tape:

  • Buy two lots of tape, that way, if you mess up you have some spare tape to help you finish the job properly.

Shake Down

With the bar wrapped and a small break in the the weather a few days later I was able to finally take the bike for a shake down ride one evening. The only problem I had was a consequence of the problem I described with the gear cable on the left brifter (the cable that connects to the front derailleur). Clearly the last minute adjustments to fix the cable tension problem (see above) had screwed something up.

I was just starting to ascend one of our local climbs (or what passes for a climb in our area) but the Centaur's release button was jammed and wouldn't drop the chain onto the small ring. Fortunately it wasn't too steep and I could use the right-hand lever to get comfortable. I figured that, for the button to jam, there must be some unwanted tension in the system. I loosened the barrel adjuster as much as I could (by screwing it into the frame lug as far as it would go - being mindful not to put my fingers through the spokes of the front wheel). This seemed to do the trick and the button could then be pressed and the chain shifted down. Of course, at this point there wasn't enough tension in the cable to shift back up. After a bit of fiddling I found an adjustment point that seemed to work enough to get me home but the whole thing had to be redone from scratch. That is, I had to remove all the tension from the cable, remove it from the clamp on the derailleur, reset the barrel adjuster (by screwing it in) and then reattach and tension the cable as per the instructions.

What happened? I'm not 100% sure. It seems likely that the cable had become too loose (as these things don't usually get tighter by themselves) and that I had pushed the level too far beyond the third click at the previous up-shift (the lever itself also appeared to be jammed). Either way, the levers feel a little more fragile than then old 105s I'm used to - a result of their lighter weight I expect. They're also quite expensive so I was pleased to get through this glitch without the need for more expensive spare sparts.

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