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16

You actually need something sticking up above the top of your steer tube. It can be either a spacer or the stem itself. This is because the top cap squeezing down onto the stem/spacer stack is what keeps the headset bearings snugly in their cups. If the top cap is flush with the steer tube, there will be play in the headset which is bad. Park Tools has a ...


15

No, it would not be particularly safe. The steering would get extremely twitchy and difficult to handle.


13

Almost all stems (aside from a few very expensive carbon ones!) are designed to be mounted either way around. The pressures are in the same direction regardless of which way up it is. (they're just reversed) They are designed to be used either way up, otherwise manufacturers would need to produce double the number of stems to create positive and ...


12

It sounds as though you are talking about what Sheldon Brown term "reach", which is normally measured center-to-center along the direction of the extension So this does not take into account the angle of the stem, which could reduce the length forward that the handlebars extend by a small amount if they are on a large angle up or down.


12

A shorter stem does make your steering quicker, it also enables you to sit more upright and gives more leverage on the handlebar. The longer stem gets you more forward and in a better position for climbing but I think it makes low speed steering awkward and is uncomfortable for long stretches on the bike. I went from some ungodly long stem (100+mm) with a ...


11

I believe that's the logo for Dyno which was acquired by GT in the '80s.


9

No, the clamp that mounts to the steerer is not a standard height. There will be slight differences in the stack height of the clamp itself between different makes and models of stems that can typically be accommodated for with addition or subtraction of a small number of spacers, or the difference may be so slight that you don't have to change your spacers ...


8

For quill stems, you can use a rubber cement to glue a ball-bearing into the socket on the stem bolt, making it so you can't get at it with an allen key. You'd obviously want to use a glue that can be removed with a solvent, so that you'd be able to do regular service.


7

Measure the handlebar itself, while unmounted from the bike, at the center most point of the bar. Use a digital or vernier scale caliper. The bar from the 2009 Bianchi Cortina is a 25.4mm MTB handlebar, with about 2 inches of rise. I expect yours will be as well. Do not use a 26mm bar, although you can likely mount it on the stem, because the installation ...


7

That's scary, you shouldn't be able to do that. It sounds as though you can straighten it easily too. If you straddle the front wheel facing backwards can you twist the bars in the fork easily? If so, definitely tighten it up. Firmly. You should not be able to move that! Who put the bike together? If it's new, take it back and talk to the owner of the ...


7

I'm going to recommend that you NOT do this. There were in the past manufacturers of 1" steerer suspension forks - though I'm not certain that they're are still sold. It is important to note that bicycle frames built to accept solid steel forks have different geometry than those built for suspension forks. The frame is designed for a fork that doesn't have ...


7

It's definitely possible that the bottom bracket height is lower than your previous bike and/or your crankarm length is longer. The BB could be lower to improve handling and I have definitely seen longer crankarms on large bikes. A typical measurement is 175cm but you could see 170 on a small frame or 180 on a larger frame. The longer crankarm would be ...


7

Quill stems are in general better for adjustment -- you have far more height adjustment than using a quill to threadless adapter like this: You'll probably end up combining the threadless adapter with an adjustable stem like this: in order to tweak the adjustment. They do make adjustable quill stems: which will give you more adjustability for ...


7

The main advantage is aerodynamics, but it should also be cheaper, lighter and stronger than a two-piece combination. Aside from the shaping, the fibres will run continuously through both "parts" so there's extra strength from that and there are also no stress risers at the joins making them stronger again. In practice the strength and weight are a trade-off,...


6

In the BMX world, they use minimum offset or zero offset necks for flatland. The minimum offset options allow you shorter reach without causing problems being backwards. These are some options (the neck/bar combo might not help, but it was shown as examples of options that exist) In the picture you see a zero offset zero angle bar-neck combo, a minimum ...


6

There should be no difference, other than the quality of the materials and workmanship. One can clamp just as tightly as the other, and both will be apt to produce the same symptoms if the bar is slightly undersized or too flimsy at the mount point. In both cases, if you do have a slightly-undersized bar you want to keep you can grind down the faces of the ...


6

A problem many hit when trying to straighten the stem is that they end up aligning the stem with the bike while the wheel is almost straight. A degree or two isn't noticeable until you are riding and then it really bothers you. Instead of trying to align three things (bike, stem, wheel), turn the wheel about 45 degrees. Now align the stem (I generally do it ...


6

There isn't always one size frame which fits a person well in a given model line of bikes (there may be 2 or more - probably 2 if someones on the border of sizes). In some cases, you can get multiple models to fit by swapping out stems and seatposts and saddle and handlebar adjustments or swaps. However, this is highly dependent on the particular model of ...


6

Any frame can support a range of rider sizes by adjusting (among other things) the seat post and stem. However, as you might suspect, there are compromises to be made. And, there are limits to how big of a rider can fit on a given frame. I'll explain a bit more below to illustrate these points. You can adjust the seat post by making it higher (may ...


6

This is your stem. As you can see, it is the whole unit from the bars to the top of the fork, including the adjustable bit in the middle. Most dan't have this and I think this is where the confusion is coming from. To remove your bars for packing, it is usual to remove the 4 bolts on the face plate on the stem. That is the part immediately touching the ...


5

Assuming the stem was chosen by the manufacturer, it's required torque as printed on the stem should be within the ability of the fork steerer to support. If the stem says,"Max Torque 10Nm" as opposed to just "10Nm" then start with a lower setting around 6Nm and work up slowly until the stem clamp will not slip on the steerer. If only the number is ...


5

As long as you're putting on the same size stem (steer tube size, not length), which you should be doing unless it came with spacers/shims, then yeah no problem. If the clamping area is taller, you may need to get a longer bolt to reach the star nut, but then you'll also have some stem above the steer tube and that's no good either. Odds are though that you'...


5

At 10 o'clock there is a wedge that holds the handlebar. Taking off the plastic cap at the end of the stem reveals the bolts for tightening the stem and handlebar.


4

In addition to Moz's answer, with which I agree, a stem riser can affect the handling of a bike, and it's safety. In most cases, they are fine and perfectly safe. Any thing like this can be carried too far, however, and your frame is designed with particular limits on the amount of leverage placed on any part of the frame. There are always extra margins ...


4

Moving your bars is probably going to move your centre of gravity which is likely to affect the handling of the bike. That said if the only change is that your elbows are more bent it might not make a big difference. A shorter stem will move your weight backwards that means: The bike will be more stable and less twitchy. It will be easier to move your ...


4

I measured five quill stems that I have, three steel and two aluminum. The overall lengths vary from 5 1/2 to 6 1/4". The minimum insertion length was 2.5 to 3.0 inches. There was not a consistant ratio of length to minimum insertion. It is possible that the insertion length increased on newer bikes due to safety/liability concerns. If you haven't got at ...


4

Changing from 50 to 65 (or the opposite) is definitely noticeable. And depending on your needs, switching may improve your riding. Switching from 50 to 65 will mean more pressure on the front end. That means better cornering (the front end will not wash out easily) and more stability on the downhill. Some people also mention that it'll improve climbing on ...


4

The answer is trigonometry. Most bikes have a headset angle of about 74°, give or take a degree. Over the adjustment range you're looking at that degree doesn't make a difference. Here, tan(74 degrees) = height change / reach change = ~3.5. So to get a centimetre of reach change to need to lift the stem 3.5cm, putting the stem up reducing the reach. Or you ...



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