Advertise on Bikeforums.net



User Tag List

Results 1 to 20 of 20
  1. #1
    Senior Curmudgeon
    Join Date
    Jan 2005
    Location
    Directly above the center of the earth
    My Bikes
    Electra Townie 1-speed with basket & fenders
    Posts
    3,304
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Can I extrapolate frame sizes?

    So I've got a 60cm Klein Navigator that is just a bit too big. There's a 56cm one available on e-Bay. Too big a difference? The "best fit" bike I've owned measured exactly 58cm from center of cranks to center of top-tube.

    The question is, how consistent is the sizing of frames? I know different manufacturers measure differently, so my "best fit" bike measurements may not match Klein's sizing even if I could get a 58cm Klein.

    I think that I may just have to give up and insist on a test ride before buying, but if I can exchange my "just a bit too big" Klein 60cm frame for a smaller Klein via e-Bay, is the chance of a better fit worth gambling the postage amount?

  2. #2
    Senior Member
    Join Date
    May 2005
    Posts
    2,259
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    My gut tells me that this is too big of a decrease in size, since you described the 60 as "just a bit too big." Also, as has been pointed out many times in here, top tube length seems to be the more important gauge of the true size of a bike.

  3. #3
    Senior Member jazzy_cyclist's Avatar
    Join Date
    Sep 2004
    Location
    North Central Massachusetts
    My Bikes
    Cannondale R600
    Posts
    1,281
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    It can be a bit tricky. I would look for a web site that publishes the frame geometry so that you can compare the differences and how the size is measured.

    You can't adjust standover, so if the frame's too tall, you're out of luck. But if you can stand over the 60 then you can obviously stand over the 58.

    I'd agree with others who say the top tube is an important measurement. If it's too long, you will be straining to reach the handlebars (too short and you'll be cramped up). You can correct this to a degree with a shorter/longer stem, and most top tube increments are only 2 cm. But a test ride would really be the best.

  4. #4
    OM boy cyclezen's Avatar
    Join Date
    Jul 2005
    Location
    Goleta CA
    My Bikes
    a bunch
    Posts
    3,011
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FarHorizon
    So I've got a 60cm Klein Navigator that is just a bit too big. There's a 56cm one available on e-Bay. Too big a difference? The "best fit" bike I've owned measured exactly 58cm from center of cranks to center of top-tube.
    The question is, how consistent is the sizing of frames? I know different manufacturers measure differently, so my "best fit" bike measurements may not match Klein's sizing even if I could get a 58cm Klein.
    Frame sizing is all over the board, in a 'small increments that mean a lot' sortta way.
    wouldn't Klein have specs on their site for their models - all the bike makes I've looked at have geometry specs for their models - to include some of the more recent discontinued models?
    I might be close to your 'size' (maybe?), I'm at 5' 11", inseam of 34.8" (floor to sitzbones). I also find 60cm just a bit big and 58cm has mostly fit well. Seattube doesn't mean much these days, what with the range available thru modern posts. But toptube and corresponding head and seattube ANGLES do have an effect on positioning.
    I recently went to 2 newer frames, all steel, but both sortta average in spec. a Marin 57 cm Trevisio and a 56cm Torelli Corsa Strada. I really like both and both fit really well when set up.
    I compensated for the slightly shorter toptube with 1 cm longer stems. Seattube angles are very close to what I'd expect with a 58cm, so positioning was easy.
    Only other issue was bardrop and that was/can be worked with different stem angles to get the preferred 'drop'.
    I would expect a 56 Klein to be quite close to a 58 in most specs. Now having the 2 smaller frames, they feel 'normal' and really don't ride any different than my benchmark Colnagos, which are both 58s.

  5. #5
    Let's do a Century jppe's Avatar
    Join Date
    Oct 2004
    Location
    North Carolina
    My Bikes
    Pinarello Prince/Campy SR; Cervelo R3/Sram Red; Trek 5900/Duraace, Cervelo P2C/Duraace
    Posts
    6,031
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I'm with Cyclezen about how sizing is very different between manufacturers. Different manufacturers even measure at different places on the bike. I normally ride a Trek 62 and now also have a 58 which I've made to work by using a different stem length, seat post height, etc. But, I stayed with the same bike manufacturer and model so I'd know what the different measurements needed to be. My guess is you can probably make a 56 work if a 60 is a little too big if it's the same manufacturer and model.....

  6. #6
    Older I get, Better I was velonomad's Avatar
    Join Date
    Nov 2003
    Location
    Schenectady NY & Wilmington NC
    My Bikes
    a bunch of them, most made by me, a couple made by others
    Posts
    1,630
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    What is it about the Klein that is "just a bit too big"? If it is just the top tube you can easily adjust several centimeters in reach by swapping out stems and handlebars. This is all part of fitting a bicycle.

  7. #7
    Senior Curmudgeon
    Join Date
    Jan 2005
    Location
    Directly above the center of the earth
    My Bikes
    Electra Townie 1-speed with basket & fenders
    Posts
    3,304
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by velonomad
    What is it about the Klein that is "just a bit too big"?..
    I've tried moving the seat fore & aft (a no-no for pedaling eifficiency, I know) AND various stem lengths (shorter seems better). No matter how I adjust, I just can't get enough weight off my wrists.

    With my red racer, I could hold my hands an inch above the bars with but the slightest amount of tension in my lower back. I just can't get that to happen with this frame. Before this frame I also had a 60cm Kona Dew that never quite fit either.

    My best guess is that 60cm is just a bit too large. The LBS says the fit should be OK, and they've even put me on their jig, had me pedal the Klein, and adjusted as they thought best. Still not the fit I want!

    My options at this point are to give up, go buy another bike that fits, OR to try some other 58cm frame that will work with my current components. This isn't as easy as it sounds since I want both a 135mm rear hub AND frame clearance for 700x37 tires.

    Frames that I think might fit my specs include:

    Specialized TriCross
    Specialized Crossroads
    Kona Sutra
    Kona Jake
    Klein Navigator (discontinued)

    Any others youse gals & guys might know of?

  8. #8
    Banned wagathon's Avatar
    Join Date
    Apr 2005
    Posts
    1,728
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    You can make a bike fit that is a size too small but it might take more than just raising the seat. You may have to spend a lot of time fiddling around with a setback seatpost and/or stem rise and length because the smaller bike will have about an inch smaller top tube (and wheelbase).

  9. #9
    Senior Member CrossChain's Avatar
    Join Date
    Jun 2006
    Posts
    2,024
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by jppe
    I'm with Cyclezen about how sizing is very different between manufacturers. Different manufacturers even measure at different places on the bike. .
    +1. Some manufacturers measure center to center on the seat tube, others center to top. I ride a nominally 54 cm. (ctr to ctr) Specialized and a 57cm Romulus. The Specialized, supposedly shorter and with a more upright seat tube and with a 1cm shorter stem extension still feels a bit more stretched out than the 57cm Romulus which has a more laid back seat tube angle and different geometry. The Rom 57 is measured ctr to top and the tubes are of somewhat bigger diameter. These increments add up to a different actual fit than the nominal seat tube size would suggest.

    The Point of All This: Just like Levis and Haggar may feel far different with the same set of measurements, so to with bikes. Extrapolations can be risky.
    Riding and aging don't get easier, you just get slower at slowing down.] (FiftyPlus observation inspired by G. Lemond.)

  10. #10
    Senior Member
    Join Date
    Feb 2005
    Location
    SW Florida
    My Bikes
    '04 Trek 2300; '06 Bianchi Pista; '57 Maclean; '10 Scott CR1 Pro; 2005 Trek 2000 Tandem; '09 Comotion Macchiato Tandem; 199? Novara Road
    Posts
    1,235
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FarHorizon
    So I've got a 60cm Klein Navigator that is just a bit too big. There's a 56cm one available on e-Bay. Too big a difference? The "best fit" bike I've owned measured exactly 58cm from center of cranks to center of top-tube.

    The question is, how consistent is the sizing of frames? I know different manufacturers measure differently, so my "best fit" bike measurements may not match Klein's sizing even if I could get a 58cm Klein.

    I think that I may just have to give up and insist on a test ride before buying, but if I can exchange my "just a bit too big" Klein 60cm frame for a smaller Klein via e-Bay, is the chance of a better fit worth gambling the postage amount?
    I would suggest you take a look at
    http://www.competitivecyclist.com/za...LCULATOR_INTRO
    to give you an idea of what size frame you need.

  11. #11
    Senior Member
    Join Date
    Jun 2005
    Location
    rockford, il
    My Bikes
    Trek 7700, C'dale R2000
    Posts
    2,646
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Artmo
    I would suggest you take a look at
    http://www.competitivecyclist.com/za...LCULATOR_INTRO
    to give you an idea of what size frame you need.
    Thanks. I was looking for this kind of info. The BF search does not work.

  12. #12
    Senior Member CrossChain's Avatar
    Join Date
    Jun 2006
    Posts
    2,024
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    +1 to Artmo. I used CompCyc's fit calculator a few months ago and came out with pretty much the same fit it took me years to figure out on my own. Ahh...the Internet!
    Riding and aging don't get easier, you just get slower at slowing down.] (FiftyPlus observation inspired by G. Lemond.)

  13. #13
    fmw
    fmw is offline
    Hoosier Pedaler fmw's Avatar
    Join Date
    Jul 2005
    Posts
    2,432
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    If 58 is ideal, then 56 is close enough. Rounding down in size makes fitting easier than rounding up. Many people prefer the comfort of having a frame that is one size too small - even the pros.

  14. #14
    Dharma Dog lhbernhardt's Avatar
    Join Date
    Mar 2006
    Location
    Vancouver, Canada
    My Bikes
    Rodriguez Shiftless street fixie with S&S couplers, Kuwahara tandem, Trek carbon, Dolan track
    Posts
    2,054
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Basically, the bicycle industry has gone thru a minor revolution during the past few years:

    Before: Frame size based on seat tube length, either center-to-top (c-t) or center-to-center (c-c). This meant bike shops had to stock about six or seven sizes of each frame. The idea was to get the "right amount/proportion" of seat post showing when the saddle height was properly adjusted. The result would put you into the standard road racing position, with the bars about three or four inches below saddle level and your back nice and flat in the "down" (hands on drops with elbows bent) position. Top tube length was secondary and could be adjusted by moving the saddle (usually back as far as it would go) or replacing the stem.

    Now: Compact frames (backward sloping top tube) come in three sizes (S, M, L), maybe four (XL). Seat tube length is now secondary, since the seat post adjusts for saddle height. However, frame size does determine range of stem height (since you're using a threadless fork steerer), and it determines today's primary measurement, what I would call "virtual top tube length," or "how long would the top tube be if the top tube were flat?" This determines where the handlebars are, and the various stem angles now let you place the bars at the same level as the saddle, if you so desire. Many people find the racing position to be too extreme, and comfort is good.

    Were I to buy a frame today, I would need to look at the frame specs and find the size that gave me a virtual top tube of 57 cm. This way, I could use a 120mm flat stem (-17 degrees to make it parallel to the ground), and I would trust that the seat post was long enough to put the top of my saddle between 78.5 and 79.5 cm from the center of the bb (depending on crank length). (I'm 6'1" with a 35" inseam and I normally ride a 58cm (c-t) frame with 57cm top tube). Old habits die hard.

    - L.

  15. #15
    Older I get, Better I was velonomad's Avatar
    Join Date
    Nov 2003
    Location
    Schenectady NY & Wilmington NC
    My Bikes
    a bunch of them, most made by me, a couple made by others
    Posts
    1,630
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FarHorizon
    I've tried moving the seat fore & aft (a no-no for pedaling eifficiency, I know) AND various stem lengths (shorter seems better). No matter how I adjust, I just can't get enough weight off my wrists.

    With my red racer, I could hold my hands an inch above the bars with but the slightest amount of tension in my lower back. I just can't get that to happen with this frame. Before this frame I also had a 60cm Kona Dew that never quite fit either.

    My best guess is that 60cm is just a bit too large. The LBS says the fit should be OK, and they've even put me on their jig, had me pedal the Klein, and adjusted as they thought best. Still not the fit I want!

    My options at this point are to give up, go buy another bike that fits, OR to try some other 58cm frame that will work with my current components. This isn't as easy as it sounds since I want both a 135mm rear hub AND frame clearance for 700x37 tires.
    if you are loading your wrists more than you like it is going to be either too much reach, too steep of a seat angle or the handle bars are lower in relation to the seat than your previous bike. Can you get the top of the handlebars on the Klein even with the saddle height? I assume you no longer have the previous bike, do you have pictures or a brand name that might give us some clues?

    BTW what the LBS, I or anyone else thinks is the best fit is worthless. What makes you comfortable is the only thing that matters.

  16. #16
    Senior Member
    Join Date
    Aug 2006
    Location
    SF Bay Area
    My Bikes
    Trek Portland (after numerous flings with other bikes)
    Posts
    62
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Just a thought...

    .... How high are the handlebars? I tested a number of bikes and have been amazed how all over the map sizing can be. I put two bikes (55 LeMond Poprad and 57 Raleigh Rx 1.0) side by side to figure out why the latter felt better even though the frames lined up almost identically. The answer: the handlebars on the Raleigh were two inches higher.

  17. #17
    King of the Forest Totoro's Avatar
    Join Date
    Mar 2005
    Posts
    772
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Frame sizes are not always comparable. The best measure is standover height. If it is close, you can always adjust the seat and handlebars a bit.

  18. #18
    King of the Forest Totoro's Avatar
    Join Date
    Mar 2005
    Posts
    772
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by fmw
    If 58 is ideal, then 56 is close enough. Rounding down in size makes fitting easier than rounding up. Many people prefer the comfort of having a frame that is one size too small - even the pros.
    Interesting. Rivendell advocates the opposite. But I guess it depends one how you use it and your personal preferences. I personally ride a frame that is slightly small and it seems to be a bit more agile.

  19. #19
    Elitist Troglodyte DMF's Avatar
    Join Date
    Jun 2006
    Location
    Dallas
    My Bikes
    03 Raleigh Professional (steel)
    Posts
    6,896
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    700x37 ?? Why so fat?

    I'm riding a 59cm Raleigh that I chose primarily by top tube length, sight unseen off eBay. Fits well. I determined the desired top tube length by riding different bikes and tracking that measure. Had to go to the catalog in most cases since the sales guys didn't know the number.

    Stem is raised about 1.5" but as I have been riding more and losing more of this gut, I'm considering dropping it down a bit.
    Stupidity got us into this mess - why can't it get us out?

    - Will Rogers

  20. #20
    Senior Member
    Join Date
    Jun 2005
    Location
    rockford, il
    My Bikes
    Trek 7700, C'dale R2000
    Posts
    2,646
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I am in the process of getting a new bike. I like to share some observations.
    A few years ago I started with a very uncomfortable Cannondale R2000. My plan was to go XC but I was afraid of that bike. A few members of BF made suggestions such as: Raise the handle bars, move the seat forward, consider tire pressure, consider tire size, change saddle. Long story short: It worked good enough that I successfully went XC.
    Now I found out that this bike is actually to big for me. It is 60 cm and the experts are telling me that I need 58 cm. I sort of believe them because I have a 58 cm Trek hybrid which always has felt more comfortable. I turned this hybrid into a road bike (almost) by putting 700 x 25 tire, aerobars and a Brooks Pro saddle on it.
    This long story says: 60 cm is a big difference from 58 cm.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •