I have a Ti 456 frame which I love, but I'm having a few issues with the seatpost. I'm currently using a Thomson 400mm in line one and it creaks, however if I grease it it slips down in the frame regardless of how tightly I do up the QR (a new style hope one).
I tried carbon paste in case that was enough to stop the creaking but not slippy enough to cause the post to slip - but it still creaks. I've also tried a synchros post with similar results. I suspect the seat tube is very fractionally too large for the posts, but not large enough for the next size up post or to fit an additional shim.
Any suggestions as to how I could fix this? I was wondering if I could get a seatpost that was on the fat side of 27.2? Alternatively the frame appears to have a factory fitted shim to reduce the inside diameter of the seat tube to 27.2.... are these generally glued in or just press fit? Can they be replaced?
I don't fancy swapping to a bolt up seat post clamp as I like to be able to drop the saddle easily.
Any suggestions gratefully received.
QR (a new style hope one)
There's your problem! Mine slipped like mad too so I got a Salsa which does what it's supposed to.
Interesting.... didn't think there was much that could go wrong with something as simple as a qr seat post clamp!
I used to put my Hope one so tight that I had to hammer it open and closed. Still didn't hold the post in place.
Oddly the same make of post and QR work fine on my Ti 29er.....
I use a Salsa as well and it helped cure all my seatpost slipping woes! 🙂
+1 (or -1?) for the Hope. Had their QR bits in the past, and they just don't work. You might get a bit more joy from covering the hope QR cam mechanism with grease. Helps it turn so you can run it tighter.
Go for Salsa or chromag.
A
-1 Hope
+1 Salsa
Job done!
I had the same problem with a carbon post on my Niner
with a Hope bolt up, I ended up trying to do it up so tight I popped the top off of the bolt, which wasn't actually that hard, bolt was made of cheese.
Salsa QR now and it's not budged
I think it doesn't help that Hope don't use a spherical end on one side of the clamp like Salsa, Thompson, OnOne.....
Bizzarely the ONLY thing I found that stopped creaking and slippage was a 50/50 mix of grease and carbon paste (Hope QR) 😕
had this on a inbred, tried the post in two other frames (soul+5spot) to check the post and its fine, got a onone seatlamp qr which is shown on the website with a brass bushing and they sent one with a plastic bushing which broke on fitting supposed to be a 29.8 seatube but a 30mm salsa liplock needs cranking silly tight to stop it slipping, dont think the tolerances are quite as tight as they could be imo
I've got the same problem on a Thomson 27.2 400mm post on my Gary Fisher Rig, I seem to have finally cured it with a new Thomson seat clamp (free gift woohoo) and a big shim of coke can and carbon anti slip paste!
I tried several different pieces of coke can until I found the shim size that made it nice and tight (nearly all the way round the post as it happens) and then anti slipped it and locked it all in place. That seems to have finally done the trick without needing to try and clamp the seat post tighter than they ought to be.
I've had issues with a Thomson post slipping (I think a few people have too). A nice Salsa clamp and a dash of carbon assembly paste worked a treat.
I've a 456Ti and a new-style Hope seat post QR clamp, no problems at all.
Run it with a well used I-Beam seatpost, and I've rather weak hands - so not done up tight at all.
Maybe your post is too shiny?
I had an Enduro a few years ago and the Thompson seatpost was always slipping on that until I went to a Salsa clamp.
got some carbon paste, will give it a go
got a bolted salsa liplock on it at the mo, but it needs to be scarey tight to hold it without slipping
I had slippage problems with a salsa qr seat clamp and thompson post.
Greasing the cam in the clamp helped.
Try a good old fashioned allen key clamp? Quick release is good for the small amount of time you actually want to drop your post or adjust your saddle height. All the rest of the time (ie the majority), you just want your seat clamp to hold tight, and the Allen key version will always be better than the QR version.
hmm, I have a Salsa (non QR) and just got a carbon seatpost, which I found out slips ..... quite a lot on my 100km test ride.
Did it up waaaaay tight, but still a slippery little bugger 😐
it is a bolted one, liplock not fliplock
i think the inside is slightly oversize and the outside is slightly undersized because the post just drops in to the head not a tight fit at all, and the salsa clamp is nearly closed when its tight, the clamp is a 30mm and onone say the inbreds are 29.8, will 0.2 of a mm make any difference?
There do seem to be a lot of people with issues regarding the hope seat clamps, I'll have to try a different make and see what happens.
Don't fancy a shim as it would be a pain raising and lowering the saddle.
There are definitely noticeable differences in diameter between different makes of seat post, I tried a random selection last night and some of the cheaper ones were definitely a tighter fit. Unfortunately they were also too short.
tried all the 27.2's off my other bikes, thompson, blackspire, even a gravity dropper, all loose/slip but only on the onone
i had this on my 456 summer season with both the on-one clamp and then with a fancy chromag one too (not a thompson post though). I have got some of the pace carbon paste and put that on the seatpost, as well as on the outside of the seat tube where the clamp sits. I also pulled the qr mechanism apart and put some anti seize on the contact surfaces. I can now do up the clamp with a lot less force, and the post has stayed put for the first time on my normal route.
I think it must be down to tiny differences in acceptable tolerances or sumfink.
I just sprayed the carbon seat post with hairspray, then tightened it up while it was wet and put the post in the frame. It seems to hold a previously slipping post just fine.
I had this issue with a P7.
Removing excess greese after every ride helped.
A hope seatclamp instead of the rubbish stock one helped.
Getting a Thomson seatpost (29.8) which actually fits without the shim = problem solved.
🙂
i have experienced this problem recently, also with a hope bolt up clamp. i kept tightening the bolt to stop it from slipping until it eventually broke.
as said above i have now went for a cheaper bolt up version (that actually tightens without breaking) and thoroughly clean the post. so far it seems to be working
solved now, onone sent my clamp back with a brass bush fitted and with some carbon paste slapped on its fine
apparently all onone qr 29.8 clamps now come with plastic bushes but 31.8s are still brass
Chalk. Get rid of any grease etc and just sprinkle a little bit on the post - don't know why but it works and does not need the clamp to be so tight you have trouble releasing it.
I had mad seat post issues with my P7, got a new seat post and problems solved 😀
well a thomson seat post is machined too very high tolerence so its going to be bang on, unlike cheaper seat posts. im using a hope QR and a thomson on my stiffee and in not having to much trouble with a little grease on the post.
a shim of stella can worked a treat on mine.
Had this issue with mine, when using a height adjustable seat post, with a Hope standard clamp, QR clamp and the small clamp provided by Onone.
Tried using grease, ti-prep, pace carbon paste, etc. on the post to no avail i.e. just kept creaking, slipping.
Eventually went for a double bolt clamp done up enough (not mega tight) so the post still works. Every now and then I get a wee creak, but it's not all the time.
The creaking BB is my next thing to sort out...