Seatpost slipping

jf22901

Ever since I've started using my bike for more xc riding, I've been having trouble with the seatpost slipping. I have changed the QR clamp from the supplied Santa Cruz one to a Hope one, and I have tried putting a small amount of grease on the seatpost, but to no avail. It still keeps gradually slipping down during a ride.

Is this a common problem? The seatpost is a Thompson Elite, and I'm hardly a porker (weigh ~ 13st). I only really put my full weight on it when cycling up hills. The rest of the time I usually just squat over it.

Thanks in advance.

supersonic

Some QRs can be hard to get to the required tension.

Try a bolted seat collar.

peter413

Hope seatclamps can seize up a bit some times making them harder to close.

Try putting some chain lube (preferably wet lube or Squirt is what I use) on the brass spacer and QR lever where they connect.

This will make it much easier to close thus meaning you can put more pressure on the seatpost

diy

Alternatively wrap a small amount of plumbers jointing tape around the tube where the clamp bites to give it something to chew on.

If you don't have plumbers tape then insulation tape works too, but its a little thicker.

-liam-

Surely putting grease on the post will exacerbate the problem?

supersonic

Not always.

jf22901

I was told by the guy at Cyclewise to try a thin layer of grease, as he said a small amount can increase the friction. I'll try lubricating the QR lever to allow for a tighter clamp, and if that fails I'll get a bolt-on collar.

Thanks for all the suggestions.

JamesB

Try carbon grip grease; teh little gritty bits in it may well help the grip on the seatpost

-liam-

You are using the right size post? For example, should you be using a 27.2 and you are using 27 or 26.8 mm?

spaniamania

Tighten the quick release collar using an allen key?

DLH1985

I find that using cheap hairspray works a treat (especially on carbon posts), read it on another thread. Take the post out spray all round and wait for the spray to turn tacky then tighten up - last time i had a seat post drop on me was well over a year ago before I sprayed it, no problems since!

nicklouse

so did it slip with the original clamp?

jf22901

Yes, it slipped with the original Santa Cruz clamp. As the old clamp didn't have a brass spacer, I thought that might be the problem, hence the reason for changing it to the Hope one.

The clamp is the right size - 30.9mm, as per the Santa Cruz website. I might just need to tighten the locking bolt on the QR clamp more. The problem is it is already so tight it is hard to open and close - not really quick!

nicklouse

lube up the bush and heave on it.

jf22901

nicklouse wrote:

lube up the bush and heave on it.

I'm sure I've heard things like that on late-night Ch 5 programmes. :shock:

Thanks for all the help guys. I'll get fettling later.

daveaasmith

The post on my Scale always slipped

Until someone suggested I rub chalk all over it.

Now it doesn't slip

ride_whenever

I'd be tempted to use some assembly paste, stuff works like magic!

TiBoy

I had the same issue with a Thompson Elite on my titanium road bike. Put some fibergrip which is designed for carbon but the post has not moved since. http://www.sprockets.uk.com/lubricants/ ... -1249.html