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  1. #1
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    Changing crank set and cassette

    Hello folks.
    I have a 5 years old Bianchi with full Ultegra components, STI, triple in front and 9 in the rear.
    Just got a bad news from LBS today, I need to have the BB, front crank and rear cassette and chain replaced because they are worn out. Do I have to replace the FD and RD as well if I want to go with double in front and 10 in rear? LBS said I can not. I was thinking of going with a double or compact crank set sinceI don't use the smallest chainring anyway (also reducing some weight), and also the new FSA double is costing less than what I was quoted for the replacement of the front Ultegra triple.
    Any input?
    Andrew

  2. #2
    Senior Member Deanster04's Avatar
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    Front Crankset see if you can get the chainrings for the crank. The arms should be ok. Bottom Brackets are cheap and the cassette you can decide to go for different gearing if you want. As far a going for a double you can remove the small gear and setup the limit screws on the FD to be a double.

    If you want to go for the double setup then you might have to get new FD, RD, BB, and crankset. The levers should be ok.

    On the gearing possibility check the Sheldon Brown website. Great discussion.

  3. #3
    Elitist Troglodyte DMF's Avatar
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    I doubt you need the whole crank. Usually it's just the middle chainring that wears out.

    And the BB? Are they sure? How many miles on it?

    If you let the chain go too long then a cassette is necessary. They're not too $$. Try a 11-23 with the triple and you'll find love.
    Stupidity got us into this mess - why can't it get us out?

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    Senior Member lechat's Avatar
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    if you're going from 9 to 10 speed you'll need a right hand brifter indexed for 10 gears. not sure, but i think ultegra left brifters are double or triple specific. either way there's a ton on ebay now. same for bb's and chain rings. just get the correct bcd for the rings. it's stamped on the back. if you go double you'll need a new front der. i got a mint ultegra off ebay for $16. shipping included. i'm running a gs (triple) rear der on my 50/34 it takes up the slack on the 34/12 combo. good luck.

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    Your L The only reason to go to a 10 speed is if you really want that tiny performance advantage, there is a difference in which FD works best for compact and non compact cranks. Any reason not to trust your LBS mechanics? They are correct and probably very knowledgeable on the subject...it's their job!

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    I did have some what of a crash last week, when I was avoiding an accident and ended up jumping my bike on a curb and when landed, the crank set hit first, the outer chainring was bent so was the right crank arm. I was quoted quite a bit for a new crank set, BB, shimano chain and rear cassette.
    Is there a big different in weight between double and triple or compact crank set?
    Andrew

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    Senior Member lechat's Avatar
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    a 30t aluminum chainring probally weighs 60 grams, the triple der maybe 10 grams more than a double. your talking a couple of oz.s.don't know what your ult. trip. weighed. i just bought a truvativ elita compact crank from ebay for $72.00. shipping included. it weighs 898 grams with the outboard bearing cups.

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    Elitist Troglodyte DMF's Avatar
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    Quote Originally Posted by Cool_Man View Post
    I was quoted quite a bit for a new crank set, BB, shimano chain and rear cassette.
    Is there a big different in weight between double and triple or compact crank set?
    Okay, new crank. Still don't know why you need to replace the BB.

    It's not easy to get 6503 cranks through the normal distribution channels as Shimano seems to be starving them out on 9-speed parts. But eBay is a great source. Item number: 120172933456 is a new one for $95 shipped (Buy-It-Now). Used ones can go under $60. Item number: 290170853112.

    weightweenies lists the weight difference at between 100 and 150g. Not significant.

    What did the LBS quote you for parts? Labor?
    Stupidity got us into this mess - why can't it get us out?

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