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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.


8

Those style of saddle clamp only slip like you described if they’re loose. Make sure you tighten the side bolts really good (it’s hard to break those things) and use threadlocker. A better option is to buy a 2-bolt (also known as “infinite adjust”) seatpost. Those use a better design where that slippage is not possible. Simple aluminum posts are not too ...


8

Here are a few diagrams I drew in Autodesk Fusion 360 to explain how these zero-gap stems work. According to the instructions provided with the few zero-gap stems I've encountered, you should tighten the "no gap" bolts to full torque first, then alternate between the lower bolts to fasten the handlebar. That makes sense according to the diagrams ...


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 ...


6

I believe that you should not clamp anywhere on a carbon-tubed bicycle. As @whatsisname discussed in this Stack Exchange post, carbon fiber can be made very strong, but if you want it to resist clamping forces, you have to specifically design it to do so. That would add weight. All our fancy carbon frames are designed to be strong in some directions only, ...


6

DMR make hinged clamps for mounting chain devices and bottle cages. 3 different sizes and there is a 31.8mm which should be perfect. Easy job to retro-fit an existing QR lever and bolt I reckon? Part Number: DMR-CLP-286 Alternatively here is something from a different application that would probably work. You might be able to contact the company for a '...


5

I had an exactly same problem: Ritchey WCS seatpost, Merida frame (both alu alloy) and a lightweight clamp, like in @Frisbee's answer. What I tried: Beefy clamp with various torque settings. Didn't help at all. PVC tape. Helped, but didn't last long. More torque on a lightweight clamp. I snapped it in half with only 6Nm. Hair spray. To my surprise, it ...


5

Typically, for an aluminum post you align the gaps. For a carbon post you turn the clamp 180 degrees from the gap in the seattube to minimize the chance of crimping the seatpost. Some manufacturers have their own recommendations, but they're typically in line with what the aforementioned guidelines.


4

Sounds like a perfect use for a "wedge" seat post. Animal bikes has one, other companies might make longer ones. You'd need to get a Pivotal seat to go with it.


4

Since you already modified the frame a lot, I would go further and modify it again by welding two "ears" where you could attach a real quick release, something like the picture shown below: Another possibility would be to use a (cheap?) steel clamp which you could bend open, then wrap around the frame and put the quick release through. Steel will probably ...


4

On carbon frames I've used, they have had a single bolt clamp like this one, so it should be fine. Personally, I'd like to use a slightly bigger clamp and one of those rubber size-decreasing rings to avoid cracking the frame. If in doubt I'd phone up the manufacturer of the frame and ask!


4

As you already noted you have to unscrew the remote from the handlebar and push the hose/cable into the frame so you can pull on the dropper post. Afterwards you just remove the screws from the seat clamp and pull it over the cable. Install everything backwards and you are good to go again.


4

A few things to think about: Are you using grease or threadlocker on the bolt threads? This will minimize corrosion and galling problems, and means that the same final torque value is actually clamping tighter than if the threads are not lubricated. Personally, I would use grease on this bolt, but others may differ. Ask Kalloy whether their torque spec is ...


4

You are correct that 10N is a low number for this kind of stem. It's hard to recommend carte blanche to go past a manufacturer recommended torque, but it seems likely that's what you'll have to do if it's ever going to work. The other thing to check in a situation like this is the actual physical dimensions of the parts. Most stems of any type are going to ...


4

The card is telling you to tighten the top bolts until the gap is closed, then tighten the bottom ones. It does not mean to torque the top bolts to final tightness before tightening the bottom ones.


3

Turning the lever will not tighten or loosen the clamp. The lever is a handle to allow you to twist what would normally be a nut by hand - instead of using a wrench. Using the lever as a handle twist push down on the lever and move the "nut" counter clockwise until it comes off. Put just a tiny dab of grease on the threads of the bolt and re-assemble. The ...


3

After trying a chunkier clamp and hairspray, I found this Clamp did not help much, the hairspray was better, but I was a little concerned about the solvent stuff in the aerosol. The Liquid Torque has been applied and I have done over 120 miles since, with not even a millimetre of slippage! Thanks for the other answers ...


3

First double check that it's not a simple case of it just being tight, which is actually pretty common. Remove the bolt completely and gently wedge it open just a little bit with a screwdriver, and see if it will fit on then. Do not force it - you're checking to see if it fits correctly albeit a bit snugly. If that doesn't work, and/or if it's just clearly ...


3

You can buy a braze on derailleur of the type you need and get a Braze on to 28.6 adapter. Alternately, you can get a derailleur with a larger size and get a shim. Either will be perfectly functional. Very few Mountain Bikes have 28.6 downtubes anymore so the likelihood of finding a 28.6 seems pretty low.


3

Normal aluminum cans are basically .1mm thick, so a wrap gives you .2mm. Most of the smaller scale clamp diameter discrepancies, say from a tolerance problem or from a mismatch like a 26.0 aux lever on a 25.4 clamp area, one encounters clamping controls and acessories on to bars can be resolved with aluminum can shims, or stacks of them. Going up to putting ...


3

@mikebaranczak I'm putting this as a separate answer, but feel free to incorporate this in yours. Alessandro, Mike's suggestion is that the thickness of the hanger in the BLACK position may be enough to stop the clamp closing around the seatpost. In theory you should be able to move/wiggle the hanger with the seat post clamp done up fully. If you can't, ...


3

When the bolt is tightened, is the cable hanger free to move around? If it is, then it can't be causing the problem. But if it's held in place rigidly by the clamp, it probably means that it's preventing the clamp from closing all the way. In other words, the clamp is clamping the hanger, not the seatpost like it's supposed to. Another thing to investigate: ...


3

The Cinelli spec for this bike lists it as "clamp on" and your picture definitely shows a clamp on style front derailleur. While it does seem like the factory build comes with a Cinelli branded clamp, if the frame you are buying is missing that part, you shouldn't have any trouble with a campy clamp, like this one: If you are buying a a new campy gruppo, ...


3

Aligning the gaps will allow the clamp to compress the tube a little better, therefore reducing the amount of tension needed from the clamp to hold the seat post in. And less tension means a longer life for your seat post clamp. Now, there's the issue of which way your clamp lever faces if you use a quick release clamp. Most have it facing backwards so it ...


3

According to a forumer working in bike building industry (SUNN, France), mounting the seat post clamp with its gap on top of the seat tube gap is important to ensure an equal and secure gripping.


3

It is an 'eternal' and more of a philosophic question. Both variants are out and both seem to be true and not so. It is the same on the motorcycle front. The picture of the actual stem says clearly that you should close the gap at the top. I would follow that procedure. Screw the bolt in just until the plate touches the opposite side, hand tight, not with ...


3

You should follow the instructions on the yellow cardboard. The manual contains the normal default procedure of tightening crosswise and evenly, but the second bullet point, "In case of additional instruction is added between stem body and stem cap, follow this instructions carefully." is telling you to override this normal procedure if other ...


2

My two cents: If you align the gap in the tube with the gap in the clamp, the grip will be much stronger. You'll need less force in the lever to hold the seatpost in place. If you keep them counter-aligned, you'll exert considerably less pressure, and there is a chance that the pressure will be "more evenly" distributed, although I don't "feel" it to be ...


2

0.2mm on seatpost clamp will make no difference! The tolerence is small maybe 1-2mm. a 0.2mm difference is pretty much how far the clamp moves when you tighten the binder! maybe even more. Youll see how far it moves when you take the binder off the frame and tighten it a little. the clamp goes smaller basically clamping down. so in practice it clamps the ...


2

Two shims of double drink can thickness, one to the right of the clamp bolt and one to the left, solved the problem. I speculate that the clamp had somehow bent or stretched slightly in the crash, so the bolt did not pull it strongly enough any more. Shims increase the pull, so the clamp is secure on the handlebar again. Of course, future crashes may ...


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