50

Your seat post is not all the way up, it's too far up. If you need the saddle at that height you need a longer seat post. As mentioned in comments there is usually a 'minumum insertion' point marked on the post. Don't ride the bike with the seat post too far out of the seat tube. It's dangerous as the seat post may collapse under you and you risk damaging ...


21

The advantages of seat mounted racks are that they don’t require rear dropout rack lugs; some of the seat mount racks have quick release levers so you can easily take them off (while racing or transporting the bike, etc), and are many times the only option for a rear suspension bike. The disadvantages of seat mount racks are numerous: max luggage weight ...


18

That seat post is made of carbon fiber tube and metal seat mount that plugs into it. The carbon tube is about to split and the inner part you see is the metal plug. It should be replaced immediately and should be a clear warranty case if the bike is new enough.


18

Seat posts are usually marked with a line indicating a minimum insertion point. Extending the seat post past that point poses a risk of the seat post bending, or cracking the frame. While 250-300mm seems to be the normal original size there are extra long seat posts available. Lengths of 400mm are fairly common. I did see a 700m telescoping (two sections) ...


15

Yes it's possible to hacksaw the clamp bosses off and then file the seat tube round and smooth so that a quick release clamp would slip over it. Before taking such drastic action - which will significant hurt the resale value of the bike if you care about that - perhaps try to find a QR lever and skewer that will work with the existing clamp bosses.


14

To crudely simplify things, a triathlon/TT bike position is much the same as a road position, but basically "rotated forward", so your arms rest atop the very-low-set bars. A consequence of this is, the seat ends up further forward. (source) Using Chris Froome's TT position as an example, noting the hip position versus the bottom-bracket position: (source ...


12

On old steel bikes a good reason would be to prevent the seatpost from rusting onto the frame, thus preventing saddle height adjustment. More recently I understand from my LBS that you do it to prevent water from seeping into the frame along the (imperfectly sealed) seatpost. Depending on your frame you could end up carrying one or more kilo's of water with ...


12

There are generally two types of dropper seatposts, mechanical (e.g. GravityDropper) and hydraulic (e.g. RockShox Reverb). Mechanical dropper seatposts use a spring to move the seatpost and a bolt to keep it in place. This is a very simple design and there are few things that can break or jam, and the weight is also kept very reasonable since there are few ...


11

Yes. However, it varies by type of riding and conditions. All Mountain is probably the extreme example of this (and the main market for dropper seatposts). All Mountain bikes are designed to be able to climb and for that generally one would want the seat in a "high" position to be efficient. During a technical descent, however, the seat is generally ...


11

A thorough way to do it would be to: Remove the cranks, bottom bracket and seat post. Make sure there is a decent hole between the seat tube and bottom bracket shell (might depend on the frame). Ram rags down the seat tube with a broom handle and extract them via the bottom bracket shell. Once the bulk of the grease is removed (or pushed to the bottom of ...


11

This is an XY problem. Seatposts should be lubed. While removing all lube may solve your slipping problem, it will likely do so by making the seatpost corrode into place, which isn't something you want. Instead, fix or replace your seatpost clamp, and/or make sure your seatpost isn't undersized.


10

There are seatpost shims available for a few dollars. You should get them easily in your local shop or online. I use an aluminum shim in one of my bikes with exactly the dimensions you need, it works flawlessly and looks very clean. I got it for about 3.50 € (5$).


10

Most seat posts have a "minimum" insert of 3 to 4 inches. But this varies with the material and the thickness of the post, and the weight of the rider means the minimum might still be too little. As a tall rider I frequently have my seatposts up to maximum, and have bent several over time, and have fractured one frame. Now I always buy a 450 mm or 500 mm ...


10

I agree with @ojs answer on point (1), you can just cut it with a hacksaw but with the exception of point (2) "the common consensus seems to be at least 5 cm of insertion" - the standard minimum insertion mark on a seatpost is 100mm, double this. You may get away with a bit less, like ~90mm or maybe even 80mm but 50mm would seem very much on the short side ...


10

I would suggest cutting off the extra threads. If you have access to a Dremel or similar tool it wouldn't be too difficult. Doing it with a hacksaw could be a real pain. Alternatively you could check your local hardware store for acorn nuts. The smooth ends should cover the threads which is likely doing the most of the damage.


9

It may seam counter-intuitive, but in the case like you describe a little grease may be the solution. NOTE: If you have a carbon frame or seat-post, carbon specific grease and a torque wrench should be used. It's very easy to destroy a carbon frame or post by over-tightening when installing parts. Remove the seat post and clean it and the inside of the ...


9

Looks like the new one has the same kind of saddle rails so you can remove the attachment from it and try the bare saddle rails in the suspension seatpost. It should work! Undo the two big black nuts and it should all fall off. Edit (Grigory, Criggie): The extra bits are just the clamp from an older design of seat post. So they’re not needed, but might be ...


9

You need to use high tensile bolts for high tensile positions like this. A class 8.8 bolt (metric) or grade 8 (US) or higher is appropriate. Cheese-grade steel from the local discount hardware store is not up to the task. US Grade 8 head marking. These have a min yield strength of 130,000 PSI. (900 MPa) Metric Class 8.8 head marking, with a min yield ...


8

After some more searching, it looks like I'm looking for a layback seatpost, and they're available for purchase on eBay.


8

Triathlon bikes are about one thing, and one thing only. Aerodynamics. Dan Empfield, the creator of the Quintana Roo brand, recognized this early on. Cervelo came along soon after, and their designs basically changed how time trial bikes are viewed, with their breakthrough design of the P3 in 2001 (Company history here.) This P3 design evolved, and there ...


8

This article, The Four and a Half Rules of Road Saddles, from Cervélo Cycles has been really helpful to me when pondering saddles. I think the key points are: The saddle needs to be wide enough to support your "sit bones" but not so wide that it chafes on your thighs. The saddle has to be flat enough that the part between your sit bones doesn't press up on ...


8

Pipe cutter or hacksaw cut the post well but leave sharp edges. These are easily rounded with sand paper or files (rat tail for inside, flat for outside). To get a factory-like finish you'd need a metal lathe, but a rougher finish isn't going to cause structural problems and will be hidden inside the frame. The common consensus seems to be at least 5 cm of ...


8

Hang the bicycle upside down, on a stand if you have one, but you can also simply suspend it with a bit of rope. Next, you can easily clean the inside of the tube with a bottle cleaner dipped in solvent. Since the bike is upside down, there is no need to remove the cranks and BB. Gasoline or paint thinner works well to remove grease. The last bit of grease ...


7

I present you with evidence that seatposts can, in fact, seize! Alloy and steel seatposts are both perfectly capable of seizing to both alloy and steel frames. IIRC, carbon seatpost/frame combinations may need carbon assembly paste for almost the opposite reason: to increase friction and reduce the torque required for a good grip.


7

For Aero seatposts, smack the saddle nose solidly sideways with your hand, you should hear a loud crack, this is the surface tension breaking. Seatpost should then move OK. Saw this done by ex-Pro who was Giant dealer on a Propel, made my life so much easier since I learned that tip


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

Pull the post and hold it next to the seat tube to see how far it goes in. If it does not go in far enough to be into the seat tube below the top tube you are putting a LOT of stress on the top of the seat tube. Believe that maximum mark on the seat post. A seat post is not that expensive to risk damaging a frame. This is just one (not cheap) seat post ...


7

For road bikes of that age, showing just "a fistful of seat post" was considered good frame fit and style. Otherwise the frame was likely too small for the rider. Of course that was before the advent of sloping top tubes. If the bottom bracket is not too high, stand over height of the top tube should be no problem even with such small seat post extension.


7

There are lots of clamp-on bottle cages (google link), letting you add bottles wherever you have space on your bike (this is just one design, and not a particularly good one IMO, better to have two clamps): Or some clamps that let you mount conventional cages: I suggest grabbing a couple of bottles and trying to fit them into the frame. Also, ...


7

2.8Nm for a collar on a steel/aluminum post is incredibly small. My carbon frame bike (with aluminum seatpost) specifies 5nm and 5-7 is a common value (Refer park tool website). I probably run around 2Nm, as I use carbon paste and have it no tighter than needed to stay put, but would happily go higher if needed. First have you cleaned and greased the ...


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