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I luv riding in WA
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Discussion Starter · #1 ·
Hi,

My wife bought a new bike last year (LOOK 585) equipped with full 2008 Chorus including a 39/53 crankset, a very sweet ride. A week after taking delivery of the bike she got pregnant and we now have twins. YIKES! Living in a mountainous area she is, deservedly so, begging for easier gearing hence my question. Can we just swap out the chainrings for 34/50, retaining the same crankarms/bolts and hit the road? Or do we have to buy a complete new crankset? As for adjustments, I know we will have to lower the front derailleur and remove a link or two from the chain to accomodate the smaller chainrings. Is there anything else we should be adjusting/changing on the drivetrain? Where would we find the best price on chainrings if that is the route to go?

Thanks,
Dave
 

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So. Calif.
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You'll need a new crankset with new chain rings. The Bolt Circle Diameter (BCD) has to be smaller for the 34t compact chain ring.

You didn't mention what cassette she is using, but IIRC Campy offers a 13-29t for 10sp. That's ~16% lower gearing than a typical 12-25t, vs the ~13% lower she'd get from compact chainrings. Cassettes are much less $$ than new cranksets.

But, there might be an issue with a short cage derailler if the large 53t chainring was cross-chained to a 29t rear cog ... I'm just not sure.

Best prices for USA purchasers, by a wide margin, are from the UK retailers:
Ribble, Wiggle, Probikekit, ShinyBikes.

If you are in Canada, the CAD-GBP currency exchange rate may, or may not, be as favorable as the USD-GBP rate.
 

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Yeah your gonna need a complete new crankset. IIRC if you have an 08 fr derailleur it should be compatible w/ compact or standard chainrings, but check just be sure you have an 08 FD.

I think currently your best bet would be to get a compact 08 Veloce crankset from probikekit.com out of UK. Currently you can get it shipped free to the US/Canada brand-spankin'-new for under $80CAD. Personally, if I were you I'd jump on it as their stock can be quite unpredictable. I've used them repeatedly, never had any issue w/ them.
 

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Oops!! the price I saw @ pbk was for the standard UT Veloce Crankset. But still, I'd say pbk's gonna be the best way to go. Shipping's free and, at least in my neck of the woods, very fast as well.
 

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I luv riding in WA
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Discussion Starter · #6 ·
short cage R.D.?

I measured the Chorus 10spd rear derailleur on her bike and it has a 56mm distance between pulley centres. Is this a shorty or not?

Thanks,
Dave
 

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Big is relative
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There are lots of compact ten speed cranks on eBay. You can get something nice with low miles. With UT, you only need the new crankset and twenty minutes to swap it out and adjust the FD down a smidge.
 

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So. Calif.
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My 2009 Chorus 11 also has a short cage rear derailler (measured 56mm C-C pulley spacing).

My configuration is 50-34t front chainrings + 12-27t cassette. The total "chain wrap" capacity of rear derailler is at least (50-34) + (27-12) = 31.

Therefore, O.P.'s 53-39t chainrings should work with 13-29t cassette: (53-39) + (29-13) = 30, which is less than my setup.

1) If OP swaps to a compact crankset, 50-34t and assumed 12-25t cassette:
Lowest gear = 36 gear-inches.
Highest gear = 110 gear-inches.

2) If OP keeps 53-39t cransket and installs 13-29 cassette:
Lowest gear = 36 gear-inches.
Highest gear = 108 gear-inches.

The 2 scenarios provide essentially identical gearing, and both work w/ short cage derailler.

A cassette is less $ than a crankset ... also some people don't like compact cranskets due to the bigger jump in gearing when shifting front.

I think both approaches are viable.

A compact crankset would require existing chain to be shortened slightly.

A new 13-29 cassette would require a new longer chain, but if the bike has lots of mileage, it's usually good idea anyway to install new chain with a new cassette. This an additional cost with the cassette method, which may partially even the costs relative to the 'new crankset' scenario.
 

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Irrespective of what you read a 29t cassette does work with a short cage. I use one each time I go to Gran Canaria. Even in a 29-53 configuration it worksm althbough even I wouldn:t recommend that.
 

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mj3200 said:
Irrespective of what you read a 29t cassette does work with a short cage. I use one each time I go to Gran Canaria. Even in a 29-53 configuration it worksm althbough even I wouldn:t recommend that.
Right -- that's what I said :)
 

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jpdigital said:
Oops!! the price I saw @ pbk was for the standard UT Veloce Crankset. But still, I'd say pbk's gonna be the best way to go. Shipping's free and, at least in my neck of the woods, very fast as well.
Do they charge duty when shipping to the US?
 

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cs1 said:
Do they charge duty when shipping to the US?
Usually not, unless items are shipped via UPS, FedEx, or DHL ... the private delivery services are notorious for jacked-up 'brokerage" fees and collection of gov't duties.

I've ordered from PBK, Wiggle, Ribble, and Shiny Bikes. All used the Gov't postal services, and I did not get charged any duties, even though some of my items were in principle "dutiable".

caution- Shiny Bikes uses UPS for large items (eg, wheelsets) and you could nicked for unexpected higher costs & fees - check in advance!
 

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As for PBK, the price you see listed is what you pay. No hidden fees whatsoever. Only time they've charged me any kind of shipping is when I bought a frame for my friend as it was considered oversized. You'll get the package via USPS aka "mail".

The only difference you may see in price is the exchange rate (minimal) and your credit card may charge a fee for foreing exchange (again very, very minimal).
 

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jpdigital said:
... your credit card may charge a fee for foreing exchange (again very, very minimal).
Some cards charge up to 3% , over my threshold for "minimal".

CapitalOne Mastercard, to name one, charges 0%.

I've also found CapitalOne to use very favorable exchange rates, always slightly better than what's listed on Yahoo Finance or Google Finance. (ie, more GBP for my US$).
 
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