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Here I am again, saddle height ,hey C40(5 posts)
|Here I am again, saddle height ,hey C40||bikefreax|
Oct 29, 2003 12:57 PM
|What is the best method of determining saddle height? Hey c40 you seem very knowledgeble on these things. How about your e-mail and I will send you a picture to help me decide if I bought the wrong size frame?
|lots of experimentation....||C-40|
Oct 29, 2003 4:09 PM
|Ignore formulas and concentrate on the basics. Maintain a reasonable bend in the leg at the bottom of the stroke. If I was getting on a bike for a quick tryout, I would use my quicky method of dropping the heel several cm below horizontal with the leg locked at the bottom of the stroke. This helps to insure that there will be some bend in the leg during normal pedaling.
Beyond that, you have to experiment with both saddle height and fore/aft position over hundreds of miles of "evaluation". Eventually you'll find a range that works best for you.
I strongly recommend against raising the saddle above a point that produces a significant bend in the leg at the bottom of the stroke. Nearly every time I see someone plodding along with a slow, choppy cadence, it's due to a too-high saddle.
Saddle height should be the same regardless of the frame size that you ride. The indictor of a (vertically)too-small frame would be excessive saddle to bar height difference. A frame that's the right size should produce an 8-10cm saddle to bar height difference with a moderate rise stem (80-84 degree) and little or no steering tube spacers. A set-up that falls outside this narrow range MAY be too big or too small. Head tubes on many frames these days are shorter due to the use of integrated headsets. These frames will often yield a saddle to bar height difference at the maximum of this range and perhaps a bit more, but still be the best choice of size. It would be rare these days to find a correctly sized frame that produces a saddle to bar height difference that is less than 8cm.
A horizontally too large or small frame is determined by stem length. If you find yourself needing an 80mm stem the frame's probably too big. If you need a 140mm, it's probably too small (unless you have a really long torso and ride a big frame).
My other rule of thumb for horizontal top tube frames is the vertical height of the saddle above the top tube. 17-19cm is a good range. You could go down to 16cm for small size frames and perhaps go up to 20cm for the largest frames.
Pictures are often hard to evaluate. Hard measurements usually tell the story more accuarately.
|So you're saying.....||Stinky Hippie|
Oct 29, 2003 5:33 PM
|the measurement from the top of my saddle to the top of my toptube is 18.5 cms. the drop from top of the saddle to my bars is between 8 and 9 cms. I'm using a colnago 120 mm stem with a little less than 2cms of spacers. I have no idea what the rise is -- frankly, it looks to be what we in the MTB world would call a negative 10-15 degree rise.
So I guess what I'm asking is, based on those measurements, my frame is well fitted to me in your book, yes?
I ask this because while I'm no slave to fashion (okay, so maybe I am), I notice alot of other fellow horizontal tt riders have an inch or two more seatpost showing on their bikes. I had the bike made for me and have always wondered if I should have gotten a smaller frame. The frame is basically a 57 with a 72 degree seattube. (not sure what the headtube is)
thanks for the input
Feel the gin
Oct 30, 2003 4:37 AM
|The measurements that you provide indicate that the frame is plenty small enough. I would probably would have chosen 1cm larger to reduce the spacers. If you friends have a lot more post showing they are buying frames way too small.|
|thanks, C-40. Appreciate the input.||Stinky Hippie|
Oct 30, 2003 6:23 AM
|Feel the gin, of course|| |