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Dialing-in frame setup(11 posts)

Dialing-in frame setupMaxxwell30
Apr 20, 2003 4:41 PM
Looking for suggestions regarding frame measurement/setup techniques and/or resources. I have a Giant TCR1 (55cm, compact frame). Although I'm very happy with the bike (after replacing several componants), I find my overall setup(stem, top tube, seat config) is not quite right. I have an Easton CT2 seatpost (1" offset) and 140mm Cinelli Ti stem (which I love). The problem is, I feel I want to move a bit further forward and be a little less "stretch-out" over the bike. However, the seat is in the foreward most position. Therefore, I'm left with two choices - replace the seatpost with one that has no rear offset (I feel the inch would make the desired difference), or replace the stem w/ 120/110mm. Over all, it seems I should not have to have the seat in the foreward most position in order to feel comfortable on the bike - indicating the stem is too long. I had a local and reputable bike shop measure me and the bike before purchasing the stem - which I would hate to replace (hand-made Ti, expensive). Whatever the case, I'm prepard to do what ever is necessary to remedy this problem. Any suggestions would be greatly appreciated. Thanks, Matthew
Before you do anything, try flipping your stem up.timfire
Apr 20, 2003 5:22 PM
This may not prove to be any better, but it's free and worth a shot. Flipping your stem up will shorten your effective reach.

--TK
re: Dialing-in frame setup333928ien
Apr 20, 2003 6:57 PM
Lowering the seat is another no-cost option; this is meant to decrease the vertical and, therefore, the effective distance between the seat and the handlebar. Flipping the stem would also have the same effect. Lowering or moving the seat forward could decrease performance. I would make any changes in small increments and one component at a time so that the cause of any adversese effects can be identified and corrected.
re: Dialing-in frame setupJuanmoretime
Apr 21, 2003 1:11 AM
I would look at the shorter stem. I ride a post without any offset but that's from my multisport background and having spent many years on bikes with forward geometry and liking a somwhat forward position. A 140mm stem on a medium sized bike is huge. I would look to the shorter stem, moving forward with a post that doesn't have any setback may effect your climbing while seated.
lots of bad advice....C-40
Apr 21, 2003 4:27 AM
The type of stem that you have does not lend itself to being flipped to a higher angle. The Cinelli stem is nice, but it's more flexible than most of today's open-face Al stems.

The saddle fore-/aft adjustment should not be used to change the reach to the bars. Saddle adjustment is for changing the knee to bottom bracket relationship.

Lowering the saddle to decrease the reach to the bars is also a bad idea. Saddle height changes will only reduce the reach to the bars by 1/3 the amount that the height is changed. In other words, a 3/8 inch lowering of the saddle would only reduce the reach by an insignificant 1/8".

If your reach is too long get a new stem. An open face Al stem is the best choice. Highly recommend the Ritchey WCS. If you are on a budget, Supergo has what appears to be an identical stem at a fraction of the price. The 84 degree stem can be flipped from 84 to 96 degrees, but it will also shorten the reach about 1cm.
Agree strongly.dzrider
Apr 21, 2003 4:53 AM
I think moving the saddle to compensate for the stem is a bad plan. Before buying anything I would recommend rotating the bars a bit to raise the hoods and shorten the reach. This is a very simple adjustment that can make a big difference in comfort for some people. If you want proof look at the variance in the height of the brake hoods in the peloton.
too many errors in your past posts to makes the numbers kosker333928ien
Apr 21, 2003 6:10 AM
Can you prove them?
prove what?C-40
Apr 21, 2003 6:31 AM
What specifically would you like proof of? If you mean the amount of forward saddle travel caused by a reduction in saddle height, the proof is simple, but if you don't understand trigonometry or geometry, the proof may not be comprehensible to you.

Assuming a 73 degree STA, a right triangle is drawn with the hypotenuse representing the seat post, one vertical leg and one horizontal leg. The horizontal leg of the triangle represents the horizontal movement of the saddle. The length of the horizontal side of the triangle is cos73 x saddle height. The change in the horizontal position of the saddle due to a change in saddle height is cos73 x (H1-H2). Since cos73 = .292, then a 1cm lowering of the saddle(H1-H2) will move the saddle forward .292cm. The exact ratio of saddle height change to forward movement is the 1/.292 = 3.4.
re: Dialing-in frame setupjtolleson
Apr 21, 2003 6:17 AM
If the shop that sold you this rig (and that's a big bike btw...) isn't helping you with what sounds like rudimentary setup questions, then shame on them!

Ditto to what others have noted. Saddle fore-aft is not about changing reach to the bars, it is about pedaling dynamics. Whether you are a KOPS (knee over pedal spindle) purist or not, saddle position is about pedaling, not tt reach. Same thing with saddle height. Too high or too low results in knee (and sometimes back) discomfort, not to mention inefficient pedaling.

Getting a shorter stem with 0 rise can do a lot to enhance comfort reach-wise assuming that the bike is the right size. A 140 stem is quite long on a frame that big (but maybe you're a really tall guy) so it wouldn't surprise me if you need to drop back significantly to a 120 or 110.
. . . but, feeling like you want to move forward on the saddlebill
Apr 21, 2003 6:25 AM
could mean that the saddle is too high. You slide forward to effectively shorten your leg reach. You do it unconsciously, without reference to "the numbers."
OTOH, a 140 stem is long.
Does your local & reputable LBSStraightblock
Apr 21, 2003 8:11 AM
have a shorter stem they'll let you try? If they measured you for this one & your position still feels wrong, they might let you demo a shorter one.

BTW, on my previous bike, I had the same problem as you. Not wanting to alter my seat position, I switched to a 2cm shorter stem with a slight rise. It made a world of difference, and I never had problems with the stem fashion Nazis.