Sliding saddle post

[FrankR]

I need to raise my saddle. I have a Lectric type bike, and the post is locked with one of those locking levers. I did it today, super tight, as tight as I could make it, and eventually, the saddle slid down.

I'm sure I could come up with a home hack, but, what is the Proper way to deal with this. Ideally without replacing parts, because I have a long ride coming up.

Is there something tape of or other stuff that can be put on the post that will make it less likely it will slip?

Thanks.

 

[PDoz]

Firstly, ensure the clamp is rotated so the lever / bolt line up with the section of frame that has a split - ie max clamping efficiency.

There are products designed to help the post grip - search seat post paste. Rather than buying a tube, see if your lbs can apply some for a suitable donation? They are a carbon based grit.

If that doesn't work, try a better quality clamp.

 

[OrTrek]

Everything PDoz says PLUS:

I think you have a 27.2 post. I've found they do tend to slip some. Two things:
1. After tightening the lever, then use your multi-tool and tighten the "screw" another 1/8 turn or until it stays.
2. All else fails lose some weight .

 

[tomjasz]

I need to raise my saddle. I have a Lectric type bike, and the post is locked with one of those locking levers. I did it today, super tight, as tight as I could make it, and eventually, the saddle slid down.

I'm sure I could come up with a home hack, but, what is the Proper way to deal with this. Ideally without replacing parts, because I have a long ride coming up.

Is there something tape of or other stuff that can be put on the post that will make it less likely it will slip?

Thanks.

I went to a threaded nut style with a safety head that takes an oddball driver! I've had Brookes's Saddles "liberated".
Fastenal may have a new safety nut near you.
or

Protect Seat Post Clamps With Hex Bolts Against Theft - Hexlox - Hexlox - Anti Theft for Saddles, Wheels and More.

Protect seat posts with hex bolts against theft. Unfortunately, seat posts with hex bolts are very vulnerable to theft. Anyone with a regular Allen Key/hex wrench could unfasten your bolts and steal your saddle/seat post. Quickly!. Hexlox solves this problem. Click to find out more.

hexlox.com

I had the clamp-type slide on my trikes maiden run today. All other bikes are no longer clamping syle. I don't get why they are even used. once fitted I never change the height

 

[tomjasz]

If that doesn't work, try a better quality clamp.

Sadly getting the clamp tight enough with arthritis sucks... never mind ever undoing it...

 

[Tom@WashDC]

I had a sliding seat post issue and cured it by:

1. Clean the seat post and receiver interior (1' deep) with solvent to remove all grease.
2. Spray the seat post stem and receiver interior with hair spray, let dry for 1 min.
3. Insert seat post to desired level and secure the clamp. Let it dry for 5 minutes.

~solved my problem

 

[6zfshdb]

I went to a threaded nut style with a safety head that takes an oddball driver! I've had Brookes's Saddles "liberated".
Fastenal may have a new safety nut near you.
or

Protect Seat Post Clamps With Hex Bolts Against Theft - Hexlox - Hexlox - Anti Theft for Saddles, Wheels and More.

Protect seat posts with hex bolts against theft. Unfortunately, seat posts with hex bolts are very vulnerable to theft. Anyone with a regular Allen Key/hex wrench could unfasten your bolts and steal your saddle/seat post. Quickly!. Hexlox solves this problem. Click to find out more.

hexlox.com

I had the clamp-type slide on my trikes maiden run today. All other bikes are no longer clamping syle. I don't get why they are even used. once fitted I never change the height

I also ditched my lever style seatpost clamp for one with a fixed bolt. I miss the ease of the lever clamp though since I always remove my expensive suspension seatpost & saddle when transporting the bike. It reduces weight and keeps the saddle out of the elements. There's nothing worse than riding on a soggy saddle that got wet from a sudden rainstorm. I do use the anti theft screw clamp but some thieves come well equipped these days.

I've also had good luck with with this stuff to prevent post slippage:

https://www.amazon.com/Finish-Line-Bicycle-Assembly-1-75-Ounce/dp/B0012RIEM6/ref=sr_1_2?crid=XWNZDWQ9G0FB&keywords=anti%2Bslip%2Bseatpost%2Bpaste&qid=1656854298&sprefix=anti%2Bslip%2Bseat%2Bpost%2Bpaste%2Caps%2C99&sr=8-2&th=1

 

[FrankR]

Outstanding info. Thank you folks.

tomjasz
- arthritis indeed sucks. I have regular flaring situations of stiffness but also great pain in some of my fingers. And I'm a pretend musician, so, that makes it double concerning.

Tom@WashDC - that's a really good idea, getting some tackiness from the hair spray.

6zfshdb - thanks for that Amazon tip. That's what I will try next if it fails again.​

PDoz - I lined those up, gave it one more turn of the tightness knob, and then brute forced the clamp closed. Just finished an 8 mile ride with no movement.​

Thanks everyone. Sorry for the bold above. I tried to get rid of it, but the editor wouldn't let me.

You folks are great.

​

 

[m@Robertson]

I found the best way to lock a seatpost down is to use a double post clamp. One that clamps to the frame as usual, AND the seatpost.

https://amzn.to/3a9ZQEy

The one I am linking is the pricey one. I have used this one and cheaper versions that you can find on Amazon and Ebay.

I needed one of these due to a slightly oversized, out of spec seat tube on a frame. It worked so well I try and use one on every bike I have built from that point forward. These things were originally intended to provide kinder/gentler clamping on carbon fiber frames and posts. But they aren't limited to them.

 

[chunk]

I got a hose clamp the correct length, so there was no tail hanging out, painted it black and cinched it down. Problem solved now and it came out of my junk box as usual. It also serves as a stop now for the correct saddle height.

 

[PDoz]

Sadly getting the clamp tight enough with arthritis sucks... never mind ever undoing it...

Have you tried a bigger lever?

The logical part of my brain says use tools, but the anarchist in me wants to adapt an axle QR.....unfortunately none of my bikes have old fashioned wheels ( come to think of it, none of them have QR seat post clamps)

I particularly like the one on my sons giant - twice as thick as normal, two allen keys to spread the load

 

[tomjasz]

My latest build has a $150+ seat. So no I won’t be trying a bigger lever. But thank you for the idea!

 

[6zfshdb]

I've had great luck with these clamps from Chromag:

Chromag QR Seatpost Clamp

Free Shipping & Lowest Price Guarantee! The Chromag QR Seatpost Clamp is in stock now.

www.evo.com

They have a bronze insert which eases the lever action, minimizes binding and allows more clamping force. I lube mine with a thin coat of lithium grease to smooth the action even more.

The bad news is, they are one of the most expensive clamps out there.

 

[m@Robertson]

Have you tried a bigger lever?

Take a look at that picture I posted of that double seat clamp. Scribed on it is a torque specification of 5.5Nm. Thats unusually low but the typical range is 6 and at most 8 Nm. Thats 4.4 to 6 foot pounds (i.e. almost nothing). I know on the surface it may seem counterintuitive but you really do not want to tighten the bejesus out of a seat clamp. If you follow that link and look at the first review, thats my green bike. Read the review and you'll see I sheared the bolt on that clamp as it turns out the torque spec on that clamp is over-stated (others report the same thing in other reviews). On others (entirely different design), I have farmer-tightened them and bent the ears together (I'm a big guy and mistakenly thought more tighter was more better). That can compromise the whole clamp or worst case even the frame; especially if anything is composite. I even cracked one seatpost clamp come to think of it.

Since I've had those learning experiences, I have done a couple of things:

1) Greased the seatpost lightly prior to installation as is typically recommended. As counterintuitive goes, this was all that! I know it sounds insane, but read directions on seatpost assembly and its a common item.
2. Stick to the torque spec (which means using a torque wrench at the get-go). Trust it, and it works. If it doesn't something else is wrong that needs a solution.

 

[mschwett]

1) Greased the seatpost lightly prior to installation as is typically recommended. As counterintuitive goes, this was all that! I know it sounds insane, but read directions on seatpost assembly and its a common item.
2. Stick to the torque spec (which means using a torque wrench at the get-go). Trust it, and it works. If it doesn't something else is wrong that needs a solution.

this. the people who design these things for new bikes aren’t idiots. they work. and a properly specified fastener with a torque spec, torqued properly, will not slip when used within design limits! i too used to be in the “hand tight plus a bit” camp, but am now firmly on team torque wrench. I also avoid all fasteners which can’t be torqued precisely.

 

[PDoz]

Take a look at that picture I posted of that double seat clamp. Scribed on it is a torque specification of 5.5Nm. Thats unusually low but the typical range is 6 and at most 8 Nm. Thats 4.4 to 6 foot pounds (i.e. almost nothing). I know on the surface it may seem counterintuitive but you really do not want to tighten the bejesus out of a seat clamp. If you follow that link and look at the first review, thats my green bike. Read the review and you'll see I sheared the bolt on that clamp as it turns out the torque spec on that clamp is over-stated (others report the same thing in other reviews). On others (entirely different design), I have farmer-tightened them and bent the ears together (I'm a big guy and mistakenly thought more tighter was more better). That can compromise the whole clamp or worst case even the frame; especially if anything is composite. I even cracked one seatpost clamp come to think of it.

Since I've had those learning experiences, I have done a couple of things:

1) Greased the seatpost lightly prior to installation as is typically recommended. As counterintuitive goes, this was all that! I know it sounds insane, but read directions on seatpost assembly and its a common item.
2. Stick to the torque spec (which means using a torque wrench at the get-go). Trust it, and it works. If it doesn't something else is wrong that needs a solution.

Tomjasz was talking about the difficulty achieving normal seat clamp tension due to arthritis - ie I wasn't advocating crushing frames or seat posts. As per my first post, my bikes are carefully assembled including seat post paste ( and these are dropper posts in carbon frames - hence the lovely clamp on his giant reign)