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  1. #1
    Senior Member
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    Going Down a Frame Size?

    I admit up front that I may be over-thinking this, so feel free to disabuse me of this notion.

    My two main bikes are a 2011 Specialized Allez that I built up from a frameset, and a 2010 Look 585 Optimum that I also built up from a frameset. Both frames are 61cm. The Allez gets the majority of the miles, since it's got the PT wheelset and fenders.

    When I bought these two framesets, I was coming off my 58cm CAAD9. I had just had an expensive fit session, and ended up with one of those funky cheap adjustable stems to get my bars high enough. It offended my senses enough that I bought the 61cm Allez frameset (230mm head tube) and transferred the parts to it. That HT is high enough that I had to flip the stem to get the right bar height. The top tube is long enough that I had to go to a 90mm stem to get the right reach. The Look's dimensions are a bit smaller; in fact, it's smaller than a 58cm Roubaix...go figure. I've got no plans or desires to replace the Look. I've gotten both more fit and more limber since I got the Allez. I've since lowered the bars a bit, and am still comfortable in the drops for as long as I want to stay there.

    The 2013 58cm Allez frameset has a 205mm head tube. Based on my figuring, I could be in the same position with a 10 degree stem flipped up and just the cone spacer on that frame. I'd also be using a 110mm stem. There would be a small weight advantage to the 2013 frame as well, since the 2013 fork is all carbon, where the 2011 fork has an aluminum steerer. A disadvantage may be that I might need a new crankset; I don't know whether the Specialized "over-size bottom bracket (OSBB)" would accept my standard crankset.

    Would there be an appreciable advantage to going to the smaller frameset?
    Regards,
    Chuck

    Demain, on roule!

  2. #2
    Resident Alien Racer Ex's Avatar
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    Quote Originally Posted by revchuck View Post

    Would there be an appreciable advantage to going to the smaller frameset?
    Bit lighter, a bit stiffer. The OSBB can use an adapter for your existing crank set. I'll sell you mine cheap.

  3. #3
    Old Road Racer Cleave's Avatar
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    Hmmm...

    Did the fitter look at you on the 61 cm Allez? A 90 mm stem on a 61 cm frame does not sound right for a race fit. You'll want to look at the stack and reach dimension of 58 cm Allez and compare them to the 58 cm CADD9 to make sure you are comparing apples to apples. Using head tube lengths is harder to compare these days for fit with current frame design.

    Besides what Ex said, going to the longer stem should make the bike less sensitive to steering input. Especially useful when you are elbow to elbow with someone in a corner.
    Thanks.
    Cleave
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  4. #4
    Senior Member
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    Cleave - I went back to the fitter about a year later for an update, and brought both the Allez and the Look. To get the same reach on both, I needed a 90mm stem on the Allez due to the difference in top tube length - 60cm on the Allez vs. 57.4cm on the Look. (Top tube on the 58cm Allez is 58.3cm, and for the 58cm CAAD9, it's 57.5cm.) With 20/20 hindsight, I should've gotten the 58cm Allez frameset two years ago, and I wouldn't be in this situation.
    Regards,
    Chuck

    Demain, on roule!

  5. #5
    Elite Rider Hermes's Avatar
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    A smaller frame will provide greater seat to bar drop due to typically a shorter head tube providing improved aerodynamics. However, as Cleave said, that is not necessarily the case with the new designs.

    Ceverlo went to a taller head tube and recommends a 17 degree stem for greater seat to bar drop.

    The bigger issue is whether you are low enough on the bike or working to increase strength and flexibility to get lower for better aerodynamics. Check the change in power required to hold the same speed when you lower your body 1 cm. Bike fitting is a dynamic process that takes months to perfect.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

  6. #6
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    Quote Originally Posted by Hermes View Post
    The bigger issue is whether you are low enough on the bike or working to increase strength and flexibility to get lower for better aerodynamics. Check the change in power required to hold the same speed when you lower your body 1 cm. Bike fitting is a dynamic process that takes months to perfect.
    I understand that it's a dynamic process. Right now I'm at 6cm seat-bar drop, and it's good for 100 mile rides. I could conceivably go lower for shorter rides. I could drop the bars on the CAAD9 another 4-5cm between removing spacers and flipping the stem, but I don't know how that would affect other things. I could stay on the hoods with no problem, but going to the drops would probably be uncomfortable pretty quickly. I need to get another stem for the CAAD9 before I try that.
    Regards,
    Chuck

    Demain, on roule!

  7. #7
    Elite Rider Hermes's Avatar
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    Well, I would suggest dropping the bar in 2.5 mm increments over time (weeks or months) by purchasing a set of spacer and replacing the 5 mm or 10 mm with new ones for finer control. Flipping the stem and removing largers spacers may be too much. However, 6m of drop is not much for racing, IMO. Take a look at Cleave's or ShovelHD's bikes. However, they have been at this longer and may be more flexible than you are.
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

  8. #8
    Senior Member shovelhd's Avatar
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    Flexible, I am not. I have trouble touching my toes. My hamstrings are perpetually tight.

    A proper fit is a compromise between weight balance, comfort, and aero. It is very hard to try and diagnose fitting issues over the Internet, but I'm willing to give it a try. Pictures or video are very helpful. If you could put your bike on the trainer or rollers and have someone take video of you riding on the tops, bends, hoods, and drops, in that order, all seated, that would be valuable. If not video, then pictures, one at each station.

  9. #9
    Elite Rider Hermes's Avatar
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    ^^^^ This ^^^
    "Insanity: doing the same thing over and over again and expecting different results." Einstein

  10. #10
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    Thanks, all! The question isn't so much about fit - I've pretty much got that dialed in, though it's still a work in progress - but whether going down a frame size would be beneficial. I'm going to work with the CAAD9 and follow Hermes' recommendation about lowering the bars a hair at a time and see where my limit is.

    It appears that the answer to the original question is that a smaller frame would be appropriate...now I need to figure out if I should get a new frame or have the CAAD9 powder coated. If I get some tax money back this year, it'll make the answer a little easier.
    Regards,
    Chuck

    Demain, on roule!

  11. #11
    Senior Member shovelhd's Avatar
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    Unless your CAAD is your dream bike, don't powdercoat it. You'll never get your money back. Try a smaller frame then sell the CAAD as is.

  12. #12
    I need speed AzTallRider's Avatar
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    I went from a 64 to a 62 when I replaced my Madone frame, and it's an improvement. It has an integrated seat mast, and I can just barely get the saddle up high enough, and I use a 140 stem. IMO, smaller is better so long as you can get the geo right without going to extremes with the stem. Over 140 or under 100 is extreme.
    "If you're riding less than 18 MPH up a 2% grade please tell people Coggan is coaching you."

  13. #13
    Senior Member shovelhd's Avatar
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    I didn't think O/S stems were made beyond 140.

  14. #14
    I need speed AzTallRider's Avatar
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    Moot point for me. Crashed today, and the TT of my Madone is broken... and a pedal, and a saddle, and... etc. Going to have to figure out what to do asap, given the season just started. Damn! Oh, and I'm just generally battered, but feel lucky all-in-all. Landed mostly on my back, saving my shoulder and collar bone. Gotta love TallWife (and I do):

    TW: (after of course asking about the bike) So are you able to ride tomorrow?
    AzT: The way I'm feeling now, probably not.
    TW: I'm sure you'll find inner strength tomorrow - so just toughen the F%^$ up!!!!
    "If you're riding less than 18 MPH up a 2% grade please tell people Coggan is coaching you."

  15. #15
    Senior Member
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    Bummer, AZTR! If something had to break, I'm glad it was the bike instead of your bones. Going to give Calfee a call?
    Regards,
    Chuck

    Demain, on roule!

  16. #16
    Senior Member shovelhd's Avatar
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    Oh man. Heal up quick AZTR.

  17. #17
    Old Road Racer Cleave's Avatar
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    After finishing waaay behind the main 55+/60+ field, I saw Racer Ex and AzTR in the 45+ staging area. I decided to hang around to see how they were doing at the end of their first, 14-mile lap. Unfortunately neither were to be seen. The 1/23 women went by and then shortly a support van pulled up and AzTR stepped out. From the front he looked OK, but medical staff were talking to him. Then I saw someone holding his broken helmet.

    Ex rolled up a bit later as he had dropped out of the race and gone back after realizing his charge had gone down in the crash.

    Fortunately, AzTR is mostly just scraped and bruised. The bike...well it's only money.
    Thanks.
    Cleave
    "Real men wear pink."
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  18. #18
    Senior Member VanceMac's Avatar
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    Sorry to hear, Az. And sorry about the bike, but glad you are okay.

  19. #19
    Senior Member
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    I think I've figured out how I'm going to work this. I'll get the new frameset sometime soon after Rouge-Roubaix (March 10). Most of the parts from the current Allez will go on the new one; the main exception is the compact crankset, which will go on the CAAD9 while the new standard crankset now on the CAAD9 will go on the new Allez. The fenders will also go on the CAAD9 - it's already ugly, so the fenders and associated crud from riding in nasty weather won't be as much of an eyesore. The old Allez frameset will (hopefully) be sold.

    I've got between now and then to turn a couple of guitars and some firearms into bike parts.
    Regards,
    Chuck

    Demain, on roule!

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