"Don't by upgrades, ride up grades"
I like to do a bit of bike tinkering - the good thing about my two bikes is that they are not excessively expensive in the scheme of things and I can afford a few upgrades now and then. What normally happens is that I get something new for the Focus and the original Focus parts move down to the Giant. As a result the Giant is a bit like Trigger's Broom - I have had the same bike for nearly 4 years, but the only original parts are: frame and forks; brakes; handle bars, seat post, saddle and cable outers. Everything has either been upgraded or replaced as it wore out (the most recent example of wearing out being the bottom bracket, see earlier).
Rear Dérailleur Upgrades
As a result of all these progressive upgrades the Giant ended up with the original 105 mid cage rear dérailleur from the Focus - a perfectly good piece of equipment and probably a lot better than many people have but my issue was that it never quite looked right, and this was why I had swapped it from the Focus in the first place. I was therefore hankering with changing it.
I did this by buying a new 105 5701 rear dérailleur for the Focus and moving the 5600 dérailleur from the Focus to the Giant. This was relatively straightforward and did not really have any major implications. Although I expected the 2 dérailleurs to be basically the same geometry and differ in appearance actually the 5701 dérailleur is slightly different. The jockey wheels are further apart that the 5600 model and actually the jockey cage is about 1/2 way between the 5600 short and medium models. I guess this is what is needed to work with an 11-28 cassette range which the 5701 model supports "officially". However I never had any issues with a 5600 short cage working with an 11-28.
Here are some pictures, before and after for the Focus and after for the Giant (I used my phone so they are not great quality):
Focus:
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| 5600 - Small Front, Smallest Rear |
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| 5600 - Big Front, Smallest Rear |
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| 5700 - Small Front, Smallest Rear |
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| 5700 - Big Front, Smallest Rear |
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| 5700 - Big Front, Biggest Rear |
With the 5700 deraillieur the chain looks a little short - this is because the chain is the same length as used for the 5600 model and this shows that he cage is longer, however I don't have a photo of the 5600 in Big/Big to provide a direct comparison.
Giant:
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| Giant - 5600 Short Cage, Big Front, Smallest Rear |
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| Giant - 5600 Short Cage, Small Front, Smallest Rear |
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| Giant - 5600 Short Cage, Big Front, Biggest Rear |
Note I don't ride it in Big-Big! Given that I was going from a 27-25 tooth and taken off a long cage mech I took out a few links without measuring up, with hindsight I should have checked. However the chain is almost at the end of its life so I'll measure up a new chain in the coming month or so.
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| Giant - 5600 Short Cage, Small Front, Biggest Rear |
Cassette Selection
I also knew that the rear cassette on the Giant (also originally from the Focus) was at over 6000 miles and that the gears I used most (3,4,5) were pretty worn (there was a noticable deterioration in shift quality and so needed replacing. Again not being a super powerful rider some of the gears were pretty pristine whilst others were pretty worn. However it does not seem possible to replace the individual gears and if possible it works out at a lot more cost than a new one - a symptom of our throwaway society I guess.
The choice of what to get was a much more difficult decision than the mech as there is a choice of 4 105 10 speed cassette ranges to choose from, namely:
11-25, 11-28, 12-25 and 12-27
The gears are:
11-25: 11, 12, 13, 14, 15, 17, 19, 21, 23, 25
11-28: 11, 12, 13, 14, 15, 17, 19, 21, 24, 28
12-25: 12, 13, 14, 15, 16, 17, 19, 21, 23, 25
12-27: 12, 13, 14, 15, 16, 17, 19, 21, 24,
27
I run an 11-28 on the Focus and a 12-27 on the Giant (originally from the Focus as well). I was not that keen on the 11-28 and really only wanted a 12-28 for the 28, not the 11 as I can't exploit the 11 tooth gear as I am not strong enough. Ideally I would have liked a 12-28.
The choice of a new cassette for the Giant was quite difficult. I use the Giant in the winter and throughout the year to commute so don't do very long or hilly rides. During the Winter of 2012/2013 I was managing with the 27 as the lowest gear quite satisfactorily and even managed some of the local climbs on the 25 when it wouldn't shift down to the 27 on one ride.
This suggested that on most rides I could manage with the 25 as the bottom gear. I also felt that a 12-25 would force me into a slightly higher gear and build a little more strength as it is too easy to bail out onto the 27 or 28 when it was there. I also was slightly keener on the 16 tooth the the 12-25 has that is missing on the 11-28 and this makes quite a jump for an distinctly average rider like me.
The alternative view was that if I rode a 11-28 on the Giant as well I then had a spare for the Focus and had the same gearing on both bikes meaning better consistency.
Any way after a lot of dithering I got a 12-25. Cosmetically it looks a lot better (see pictures above). I have not yet ridden many miles on it yet but I have commuted to work on it and did not really notice any difference. I felt that I changed gear more often - partly because I found all the gears a little closer and also because I am not as bike fit at the moment as I have been. Only time will tell
In reality of course its not impossible to build a 12-28 or other combinations - although it would be quite expensive. The biggest 3 gears are all on a unit carrier and all 4 cassette ranges have a 21 as the smallest gear on that carrier, and all use a 19 as the next gear, so given enough money and time one can build a cassette with ant combination of 11, 12, 13, 14, 15, 16, 17 and 19 and then select 1 of the 4 3 gear sets.
