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Suprising Measurement(18 posts)

Suprising MeasurementMr Nick
Sep 23, 2003 4:48 PM
Today I moved my hoods inward even farther after realizing that others did it and that there was no negative side effects. During this process I thought I would actually measure the difference between my seat height and handle bar height. I get a lot of flack from other riders because I have 35mm of head tube spacers and a 17 degree riser stem. Because of this FRED setup I figured my handlebars would be less than an inch below my seat, but to my suprise I measure 5cm of difference or just about 2 inches. According to what I've read a 2 inch drop is at least slightly agressive. So I am confused how I can have a decent amount of drop with such a riser stem and so many spacers? Is it the lemond frame, or am I measuring the wrong places? Or does everyone else have 3 and 4 inches of drop?
re: Suprising MeasurementDaveG
Sep 23, 2003 5:06 PM
Between the trend towards smaller frames and threadless forks/stems which offer limited height I think many folks are using higher saddle-to-bar drops than in the past. The stigma against spacers and stems with rise only makes it worse. For what its worth, I run 7-8cm of drop but I have long arms.
try again...C-40
Sep 23, 2003 5:33 PM
Measure the height difference by measuring the height of the bars and the height of the saddle from the floor and then take the difference.

Here's a guidline for the proper vertical frame size. The saddle should measure between 17 and 19cm above the top tube, measured vertically, near the (level) nose of the saddle.

The stem in that picture has a lot more than 17 degrees of rise. Looks to me like a 100 degree (flipped 80) which produces 27 degrees of rise (from the horizontal). The combination of the spacers and additional rise from the stem angle is between 6 and 7cm.

If you had no spacers and a 84 degree stem like I do, then the bar to saddle height would be approximately 11.5cm. Mine is only about 9cm. This says that your frame is 2-3cm shorter than necessary.

Next time you buy a frame, you should look for a longer head tube length. I absolutely will not buy a frame if the head tube is too short. My Fondriest is at the low limit for me. It requires either a .5cm spacer with an 84 degree stem, or no spacers and a 90 degree stem to produce the 9cm drop to the bars that I prefer.
try again...Mr Nick
Sep 23, 2003 6:04 PM
I measured using the method you said, and came up with 5cm once again. I also looked up the stem on bontrager's website and confirmed that it is a +17degree Race Road stem.

I measured my seat and it is 19.5cm above the seattube.

I measured from the top of the bar to the bottom of the last spacer and got 12.5cm
OK...C-40
Sep 23, 2003 7:54 PM
The stem angle that you quoted is an MTB designation, which means that it is 17 degrees more than 90 or a 107 degree angle. For some reason, the MTB folks think a 90 degree stem is a zero rise. Makes no sense to me.

It's really a 73 degree stem, flipped to produce a 107 degree angle, which produces a whopping 34 degrees of rise (from the horizontal). The stem alone raises the bars about 4cm more than a common 84 degree stem. The horizontal reach of this stem is also nearly 2cm shorter than the stated length, due to the extreme angle.

You have 1cm more rise than I previously calculated, or a total of 7.5cm more than you would get with an 84 degree stem and no spacers.

Based on your saddle height measurement, you could increase the size of your frame by 2-3cm with no problem.

I also notice that you use a straight-up seatpost that effectively increases the seat tube angle by almost 2 degrees and moves the saddle 2cm forward of the nominal position for a traditional road seatpost. The saddle appears to be all the way back due to the use of this post. A traditional post would give you a better range of fore/aft adjustment.
Aha! Fitting paradigm revisited: Lemonds are too long!..Spunout
Sep 24, 2003 3:51 AM
and modern headtubes (except Pegoretti's) are too short with the internal or integrated headsets.

C-40, the fellow above would be in a whole new kettle with a larger size Lemond due to the length of the TT. And you are right, the HTs are skimpy.
Lemonds are NOT too long...PsyDoc
Sep 24, 2003 3:57 AM
The TT length on a Lemond is comparable to other bike manufacturer's TT lengths. BUT, Lemond measures their bikes C-to-C and not C-to-T like most other manufacturers do. So, a 55cm Lemond has a 56.5 TT which is just like another bike manufacturer's 57cm bike that is measured C-to-T.
mostly wrong...C-40
Sep 24, 2003 5:14 AM
Lemond top tubes are not a bit longer than most brands and actually shorter than common Treks. If Nick were to buy the next larger size, only a 1cm longer stem would be required. His current 110mm, 107 degree stem has a horizontal length of only 90mm. Changing to the next larger size would be simple.
17-19 cm?djg
Sep 25, 2003 7:38 AM
I'm all for generally helpful guidelines, but given the normal variation in body types, even among racers, let alone the larger population of cyclists, and the normal variation in preferences regarding drop, ankle extension, etc., and the variation in head tube lengths, handlebars, etc. ETC., a 2 cm window seems much too small. That's not a problem if it's smack in the middle of a preferred range for a very large majority of cyclists, but I really doubt that it could be.

I think your advice about paying attention to head tube length is important and often overlooked. And I do think that this guy could be on a larger frame. But I'd pay relatively little attention to seat tube length, except as a very rough proxy for other dimensions of the bike.
hmmyeah right
Sep 23, 2003 5:40 PM
first of all, don't worry about drop, or being "agressive", it's mostly determined by flexability, core strength and your build. You don't need to look like Abraham Olano on the bike. I'd rather save my back. Screw the fred thing and ride. I'd suggest Lemond might be the worst geometry for your build though, with the long top tube. thredless headset lead to lots of spacers, and that blow, especially for people who don't understand their personal fit yet, or for people that don't want race drop all year round. I don't get the hoods thing, but if it works for you... although I don't understand how you can pull very hard if they are turned in as much as the picture looks. good luck.
Has to be put in contextKerry Irons
Sep 23, 2003 5:43 PM
What is your frame size? 5 cm drop on a 61 cm frame would be moderate. Would be a fairly big number for a 49 cm frame. Your arm length, torso length, flexibility, core strength, etc. will all influence this number.
Looks like a 57. nmSpunout
Sep 24, 2003 3:53 AM
11.5cm of drop/ (1) 5mm spacer/-10 rise stemmerckx56
Sep 23, 2003 5:43 PM
pic...and that's with 15mm of spacers!(nm)merckx56
Sep 23, 2003 5:48 PM
Who rides the bike, you or the people giving you flack?mosovich
Sep 23, 2003 7:34 PM
My .02, as my coach would say:"The hell with what everyone else says, they're aren't the ones riding the bike. Do what's comfortable!"
Saddle not levelLC
Sep 23, 2003 8:39 PM
your measuring from the nose of the saddle, but where you sit is lower. Try leveling your saddle and then measure the drop. The no setback Thompson is also making you raise the saddle more, instead of back more.

Lemonds traditionally have a longer TT so to fit you end up picking a bike that is one side smaller and you get the shorter head tube that come with it.
Can't tell from the photoFez
Sep 24, 2003 5:01 AM
Newer Thomson seatposts come with a 12 degree clamp setup, mainly to address slacker seat angles common in the full susp MTB areana. For us roadies, it makes for more even threading between the front and rear bolts. I had an old zero degree clamp and I remember one bolt being threaded in a lot and the other much less.

If you have a newer 12 degree clamp, the front is marked as such. I don't know whether it is just shadow, but it looks like you may have it backwards.

P.S. Do you have your saddle position dialed in, or are you still experimenting with it?
re: Afraid to open. nmKristin
Sep 24, 2003 5:27 AM