Rear Derailleur upgrade from Tiagra to ???



timsuren

New Member
Dec 29, 2009
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Good day all,

I have an entry level trek and the rear derailleur was damaged beyond repair in a recent cross-country move. It is outfitted with Shimano Tiagra group components, but thought it an opportunity to upgrade the derailleur now. Any suggestions on what to upgrade to? Dura-ace? Ultegra? 105s? Also, with changing out this, is there any other components that I should swap out as well? The bike has about 2000 miles on it. working on a budget of <$300. Thanks!!
 

kdelong

Well-Known Member
Dec 14, 2006
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More info is needed to answer this question. Which entry level Trek? How long have you had the bike? What kind of riding do you do?

If you put the 2000 miles on your bike over the course of the past year, then by all means upgrade to 105. If it took you three or four years to put 2000 miles on the bike, then you probably won't need or notice the slightly improved shifting of the 105 over Tiagra.

There is nothing wrong with Tiagra. It is a good component group for the casual rider. It is a little heavier than 105, Ultegra, or Dura Ace and uses more plastic than the others, so it will wear out more quickly. But it will still last for years of riding enjoyment if the regular maintenance items are taken care of.

If you are a casual rider, then stick with Tiagra and you won't be disappointed. If you are a serious or competitive rider, then you may want to upgrade. Don't get me wrong.....the increased performance that you get from moving to a higher group is not that great. You might notice a little better shifting when moving from Tiagra to Ultegra. You probably wouldn't notice any difference moving to Dura Ace from Ultegra. Dura Ace is basically Ultegra, just a little lighter from the use of more exotic materials......and it makes you lighter too, in the wallet area.

Anyway, if all that you are replacing is the RD, then you might not see any difference since all of your other stuff is Tiagra, but the 105 or Ultegra will last longer. You might consider upgrading your rear gear cluster and chain however 2000 miles is not that much unless the maintenance on the chain has been neglected.
 

alfeng

Well-Known Member
Jul 23, 2005
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timsuren said:
I have an entry level trek and the rear derailleur was damaged beyond repair in a recent cross-country move. It is outfitted with Shimano Tiagra group components, but thought it an opportunity to upgrade the derailleur now. Any suggestions on what to upgrade to? Dura-ace? Ultegra? 105s? Also, with changing out this, is there any other components that I should swap out as well? The bike has about 2000 miles on it. working on a budget of <$300.
How damaged is the rear derailleur?

Are you sure it wasn't the derailleur hanger which was bent?

FWIW. My observation is that most of the less expensive Shimano rear derailleurs are as good as the more expensive ones ... there are exceptions, but if a Shimano rear derailleur has the same silhouette, then it will perform the same if properly adjusted & maintained (lubed) ...

The difference between a vintage 200GS which I have and my normal rise, XTR rear derailleurs is mostly in the weight & finish AND the bearings (or, lack of) in the pulley wheels -- the 200GS probably weighs about 2x as much as the XTR rear derailleur because the 200GS is mostly steel & the XTR is mostly alloy ...

The Ultegra & Dura Ace rear derailleurs have bearings & the pulley wheels whereas Shimano's lesser rear derailleurs (e.g., 105, Tiagra, etc.) use bushings which need to be oiled/greased on-day-one since it seems that Shimano doesn't bother to ...

Because the cost differential between a 105 & an Ultegra is minimal, most pre-6700, Ultegra components are a best-buy for almost everyone because it is hard to find the stuff below 105 at a bike shop. Letting mail order OR eBay be your friend will allow you to find/buy the components below the 105 line.

Presuming you are using 9-speed shifters, I would suggest that you consider getting an SLX or XT rear derailleur because it will give you greater options with regard to cassettes ... i.e., you can use a cassette with a wider gearing range with less effort.

The Shimano 950/952 [the primary difference between the two is the number of teeth on the pulley wheels] XTR rear derailleur has generally been my preferred rear derailleur on my road bikes.

The caveat to choosing most Shimano MTB rear derailleurs is that many are now "Rapid Rise" (reverse movement/pull) ... some of Shimano's MTB rear derailleurs (like the SLX) only seem to be available as Rapid Rise, now ...

Rapid Rise should actually be a 'plus' with Shimano ROAD shifters when shifting under load (i.e., going uphill) because it seems to be a benefit on MTBs ...

While I prefer [and, recommend] Campagnolo shifters, I've mounted a Rapid Rise XT rear derailleur on one of my road frames which I will eventually mate with a pair of Shimano shifters if I ever get motivated enough to complete the build (I need to put a chain on the bike + wrap the handlebars); and then, I'll do a road test to confirm the superiority of the Rapid Rise rear derailleur with the Shimano road shifters to using a 'normal' rear derailleur ... MANY people claim they don't have a problem shifting to a larger cog with their Shimano shifters when their drivetrain is under load; so, if you haven't experienced balky shifting then don't even bother to consider a Rapid Rise rear derailleur.

Anyway, THAT's a long-and-convoluted way of saying that you should let your budget-OR-ego be your guide in choosing a replacement rear derailleur.