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Finally installed 60 mm stem. Handling is fine.(14 posts)

Finally installed 60 mm stem. Handling is fine.Eug
May 14, 2003 9:26 AM
So despite all the comments that a 60 mm stem is going to destroy handling, I find it's fine. It's a little more "respsonsive" than say a 85 mm stem, but it's not as if the bike is twitching all over the place or anything.

(Mind you, if I had gotten a slightly smaller bike with a shorter top tube I wouldn't be needing a 60 mm stem.)
of course...C-40
May 14, 2003 10:00 AM
The length of the "steering arm" is only reduced by about 15% by changing from a 120 to a 60 stem. The "steering arm" is a straight line from the point of hand contact with the brake hoods or bars to the center of the steering tube.

The steering will be a bit quicker, but mainly at low speeds. At normal riding speeds, you should notice little change. After a few rides, the new feel will be "normal".
Home schooled?PaulMC
May 14, 2003 1:15 PM
If the steering arm is the center of the steerer tube to the hoods, how is a 50% reduction in stem length on 15% of steering arm? Average bar reach is about 100mm, often much less. So stem(120mm) + bar reach (100) = 220mm

220 - 60 = 160

160/220 = .727 or 72.7 percent meaning a 27.3 percent reduction.

If the bars have less reach, the difference is greater. If you're riding the tops, the reduction is 50%.
Not sure who was home schooled, but I get same answer as C-40andydave
May 14, 2003 3:15 PM
It's the simple math that always gets you.
mechanical engineer...C-40
May 15, 2003 5:19 AM
Before slinging insults, consider that the math is high school level geometry. You have proven that you paid no attention in high school.

The steering arm can be considered as the hypotenuse of a right triangle with one side being 1/2 the width of the handle bars and the other side the combined length of the stem and the distance from the center of the bars to the contact point with the hoods.

The steering arm length is the square root of the sum of the squares of the other two sides. Typical values for the two sides with a 12cm stem would be 22cm and 21cm (1/2 bar width0. The steering arm length would be the sqaure root of 925 or 30.4cm. With a 6cm stem, the steering arm length would be 26.4cm. The difference in the two lengths is about 15%.

If you consider the situation where the hands are on the top of the bars, 1/2 bar width would be reduced to around 12cm. Run the numbers and you get steering arm lengths of 13.4 and 16.9cm for 6cm and 12cm stems, respectively. The difference in this case is 21%, not 50%.
Same, same .....seejoy
May 14, 2003 10:06 AM
I bought my 1st rode bike last year,on a very tight budget, a "used" C'dale for $350-. A tad too big,no standover room at all, but the price was right and the bike was in very good condition. Being very short waisted I never felt comfortable with the stem that came with it,which was 110mm. Now I have a 60mm Salsa SUL. Responsive is a good discription on the handling but it works for me. I've promised myself that if I continue riding till I am 50 yrs.,(another 3 years), I will buy myself a new bike that fits me to a "T".
Where did you find the 60mm stem?Lowend
May 14, 2003 10:31 AM
what kind and how much? I have been looking for 60 or 70 but can't seem to find anything smaller than 90mm for road bikes. I found DH and BMX stems as small as 45mm.
HereEug
May 14, 2003 10:41 AM
At www.supergo.com but www.coloradocyclist.com has some too.

After doing the mail order thing I found one at the corner LBS - www.dukesonqueen.com - for the same price. Doh!
P.S. Mine is threadless. nmEug
May 14, 2003 10:54 AM
nm
Lots of placesKristin
May 14, 2003 10:51 AM
As far as quills go, Salsa makes one. So does Profile. I just installed a Profile 60mm 105 degree (slight rise) stem. I chose a Profile because it has longer quill and I needed the height.
I just went the other directionTNSquared
May 14, 2003 12:31 PM
I recently replaced a 110mm, -7 degree stem with a 130mm -17 degree stem. My lbs and everyone else I talked to tried to talk me out of it, warned me it would be uncomfortable, that there was no reason to put my back through that, etc. But I am all torso and felt a little too compressed through my back with the 110.

Now I'm comfortable and happy - very relaxed on the hoods and stretched and low in the drops without overreaching.

Gotta go with what works best for you.
You might even grow into the longer stem one dayLC
May 14, 2003 2:18 PM
I don't know exactly why, but over the years I find that I can use a longer stem on that same frame that I used to be too stretched out. I think my back muscles must be stretching? If you put in lots of miles you might end up back with that old stem!
Possibly, but the frame is too big for me. nmEug
May 14, 2003 6:32 PM
your frame's not too big for you; common misonception.Steve_0
May 15, 2003 3:51 AM
(of course, I dont KNOW this, I merely suspect this based on today's trends of sizing bikes WAY to small).

You seem to think that a amaller frame will move the bars closer to you; but that's only partially correct.

Certainly, with a smaller frame, the head-tube (typically) moves towards the seattube, but the top-tube also moves towards the bottom-bracket, resulting in a shorter head-tube. This shorter head-tube limits the rise in the quill by an equivalent amount. Additionally, rise delta combined with the HTA results in an ~.3 forward offset (thereby extending reach, or at best, offsetting the 'benefit' of the shorter TT).

Typically, for any given frame, shortening reach is best accomplished by RAISING the bars, NOT by shortening the TT. Exception being, of course, if you're limber enough to crimp the waist for the too-small frame. Based upon your 60 mm stem, I doubt you are (like most of us).