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Stem Reach Question(14 posts)

Stem Reach Questiondaniell
May 25, 2002 5:39 AM
Can't figure it out. I went from a 10cm (-17 degrees) stem to a 11cm (90 degrees) stem. The reached incresed more than 1cm. I thought that it would be .5 cm.

Daniel
did you remove spacers?DaveG
May 25, 2002 5:57 AM
You are right, if the stem height is the same the delta should be .5 cm. But if you removed any spacers with the higher rise stem you are effectivley moving the stem forward.
How are you measuring "reach"? (nm)B2
May 25, 2002 6:46 AM
Stem geometry chart!Check here.........................Justride
May 25, 2002 7:53 AM
http://www.habcycles.com/fitting.html
stems not all measured the same....C-40
May 25, 2002 7:59 AM
Lay a scale along the top of both stems and measure the length difference from the center of the steering tube to the center of the bars. Not all brands are measured the same. It always pays to measure before mounting the stem. Theere's also the chance that one of the stems is not the size that it's supposed to be. I've even found different models of the same brand that didn't measure the same (Ritchey Pro & Ritchey WCS).

As another poster also noted, the reach will increase if you removed spacers, by .3cm for each 1cm of spacer removed.

If you're measuring reach from the saddle tip to the center of the bars, be sure that you didn't move the saddle.
re: Stem Reach QuestionB2
May 25, 2002 9:48 AM
I'm not sure if my math is right, but if it is, it looks like the horizontal position moves "out" 1.52cm (this seems to concurr with the chart posted above) and the vertical positon is raised by 3.22cm.

Now if I make some REAL bold assumptions about riding position and use my frame sizing to estimate the shoulder position, I come up with a net difference of 2.51cm less (shoulder to handlebar).

The truth be known - I'm procrastinating doing a plumbing project on the house. At least it's raining.

Bryan
re: Stem Reach Questiondaniell
May 25, 2002 12:49 PM
Thank you all so much for taking the time to reply to my question. A little more background might clear it up. Both stems are Ritchey. The original stem was 10cm long with a -17 rise. I have a steel steerer and had 2 1/4 inches of spacers under it. I became aprehensive that the steerer tube would break. I purchased a 11cm stem with a 90 degrees. I took out about one inch of spacers. The reach has increased more than 1cm. Any opinions and suggestions would be appreciated.

Daniel.
re: Stem Reach Questiondavet
May 25, 2002 1:41 PM
Anytime a stem is lowered the reach is increased. When you took out 1" of spacers, the reach was increased more than you thought, even though there was a small rise in the 'raw' stem angle.
that's about rightDaveG
May 25, 2002 2:17 PM
the 90 degree 11cm stem added .5 cm of horizontal reach. Dropping the stem down 1 inch moved the stem forward another .75 cm. If you go with a 10cm 0 degreee stem you will still have additional stem height (2.9cm)above horizontal and the reach will be 10.3cm taking into account the 1 inches of removed spacers.
that's about rightdaniell
May 25, 2002 3:30 PM
Thank you Dave, I now understand what is going on. do think that think that 1.25 cm more is significant?

Daniel
that's about rightDaveG
May 26, 2002 4:46 AM
I made this same mistake on a bike I was building up this spring. I could definitely feel an extra centimeter of reach, but I'm fairly picky about such things. I went back and bought the shorter stem. If you are interested, I have an EXCEL spreadsheet I put together that calculates handlebar reach based upon a variety of factors including stem length/angle/height, top tube length, saddle setback, etc.
that's about rightdaniell
May 26, 2002 5:33 AM
I just flipped the 10cm -17 stem over. It seems to be the answer. I must ride it of course to make a determination.
I too felt the difference while riding. If you could email me the spreadsheet it would be appreciated.

Thanks

Daniel
that's about rightDaveG
May 26, 2002 5:57 AM
let me know your email and I'll send the sheet. It runs on Excel '97 or above
that's about rightdaniell
May 26, 2002 12:15 PM
Don't have Excel, but thanks anyway.

Daniel