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17

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 ...


14

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 ...


14

Just replace it. The part is called quill stem, it is not threadless-compatible, and it is still widely used. The only type of quill stems I heard of have 1 inch diameter, so you can just find one that is of the same/similar height and length. The simplest is to take it to a local bike shop and they will do it for you. If you want to replace it yourself, ...


12

Here's how I would fix the problem. This could all be done by somebody with basic tools and basic knowledge. Get a quill-threadless stem adapter and a new stem. This will allow you to fit the new stem to the handlebars without removing anything from the bars. The old stem can be removed destructively by removing the cinch bolt and prying the thing apart ...


11

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


10

Short answer: probably. As long as the stem and handlebars are metal, or composite that can handle the stress of the reversed position you're not going to have mechanical problems. Long answer: Unless you are riding with your hands off the handlebars what matters is the position of your hands relative to the steering axis. As long as your hands are a ...


10

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 ...


10

What you have now is a bit of a hack, but it could be good temporarily so long as you don't over-stress things somehow, and if you can tolerate the lower handlebar. (Note, I haven't seen how your stem is cracked and so can't tell how bad the situation is.) It's not likely to fail catastrophically (so long as you're not hot-dogging on the thing) but the ...


10

The cap and bolts are readily available, if you want no need to stick to a boring round black thing - they come in all sorts of weird and wonderful shapes, colours and functions. You can get them with bottle openers and clocks. The cap and bolt is only needed to set the preload on the bearings when installing the stem. Once the stem bolts are done up, the ...


9

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 height and ...


9

I'd call that part garbage, sorry. You've overtightened it enough to tear apart the metal, and that toothed flange is probably custom. I would suggest replacing the whole unit with a different brand. The one pictured APPEARS to be a threadless stem, but with the steerer clamp down below and the hinge/knuckle up on top somehow. This is quite unusual. ...


8

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 ...


8

I have reversed the stem to bring the bars closer. I found no difference in steering or safety. If a reversed stem is needed, use it without worry. My answer is specific to "cruiser bars," or "cow horn bars" that do not interfere with the top tube.


8

In practical terms, it's impossible to tell for sure in a case like this. It's probably fine, but there's no way of knowing absolutely via visual inspection. The surface indentations from the stem windows do occur naturally even with consistently correct torque on the fasteners. They're pretty normal to see. It would be a good idea to get it as clean as ...


8

This is a traditional quill stem, meaning it's shaped like a "7", with the vertical part fixed inside the steerer tube by a wedge bolt. There should be an allen bolt at the top--it looks like it might be covered by a rubber plug here. Loosen that and give it a light tap with a mallet to dislodge the wedge. You should then be able to raise the stem. ...


7

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 ...


7

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 ...


7

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 ...


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

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

That's the fork steerer. The fork has to be replaced if you want it taller. That, or perhaps, you could add another spacer to gain a marginal 10/20mm.... Replace the forks if you're desperate. Once you unbolt the stem, the forks can just drop out if you're not careful. Replacing the forks may not be economical to replace, and if so, I'd replace the whole ...


6

Adjustable stems follow a couple different design schemes, all of which involve some interlocking toothy bits that hold the angle in place. If the angle isn't changing, the toothy bits are still locked together. There's probably a bolt on the underside of the stem extension. If so, that's what locks the angle adjustment in place. So you loosen the side ...


6

Sounds like you have a Quill Stem, which has a single large long bolt going down into the steerer tube, which is part of the fork. Here's a cutaway showing what's inside. Generally speaking they're fairly corroded over time. The thing labelled Clamp in the diagram is more normally known as a wedge or expander. So you need to get some penetrating oil into ...


6

You have an older type of stem that is used with a 'threaded steerer' fork. In this system the fork is held on by the large nuts on top of the head tube, the stem is held in the steerer tube with a wedge that is tightened by the bolt on top. On newer, now much more common, 'threadless' steerer systems the fork is held on by the stem clamping the steerer ...


6

There is no absolute 'correct' way to get a lower more aggressive position. You probably can get a lower, more aggressive position on a hybrid bike by adjusting the stem angle and length, but how much lower depends on the inherent stack and reach geometry of the frame. You are also limited by flat bars which obviously do not have the drop sections that ...


6

You have the sort of headset where the adjustable race consists of a plastic shield fixed to a steel piece that has the bearing surface and the wrench flats. I think it might be a Shimano Exage Sport. If you have access to the sort of used bike/parts shop that has bins of old stray headset parts, you might be able to find a replacement. But what you've got ...


6

There is no magic formula for handlebar position, so some experimentation is necessary. If you feel your hand should be further forward, get a longer stem. Think about where your hand want to be on the drops and decide if you will go 1cm or 2cm longer. You can experiment with bar height. If you have spacers on the steerer you can move the stem up and down. ...


6

The specified torque in your case most likely applies to all four stem plate bolts, and most probably to its two steering tube bolts, that is, only to all bolts sitting in the stem itself. 8 Nm is an adequate value for an aluminum stem. Many other bolts on the bicycle typically require less torque values (other things sitting on the handlebars typically ...


6

Frame tubing is generally standardized by external diameter to imperial dimensions in increments of 1/8 inch, which makes it a lot easier to standardize things like front derailleur clamps. Seat tubes therefore tend to have external diameters of 1 1/8” (28.6 mm), 1 1/4” (31.8) or 1 3/8” (34.9 mm). Handlebars are similar. Though there has been more variation ...


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