Have just built up my new frame and on first ride today the dropper has slipped down. If I do the hope seat clamp up to the torque it says (8nm) the dropper doesn't work. I can get to about 3.5nm before the post stops working.
The post is a brand x and the frame is pace.
I have thought about using carbon paste but is that a recipe for disaster with a aluminium post in a steel frame?
Or does anyone have any other ideas?
Thanks in advance
Use carbon paste, it will be fine
I've had the same issue with a new pace frame with hope clamp and E13 dropper. That was slipping at 8nm and with carbon paste! It must be at 10nm now but at least the post is still functional. I'll try swapping with a oneup post on another bike to see if that helps.
Friction paste can be needed to allow some droppers to work in some frames.
Some friction paste will damage anodizing resulting in accelerated oxidation of the aluminium.
Pick your poison.
I have a Brand X on my Ragley with a Nukeproof clamp and a OneUp on my ebike with a Hope clamp.
I don't use a torque wrench for seatposts, just do it by feel but pretty certain they are both in excess of 8nm
Don't have issues with either of them tbh.. If your post is refusing to work at 3.5nm, maybe you have a defective post with thinner walls than spec?
FWIW I've been using Finish Line Fiber Grip for years on aluminium and steel frames, bars, seatposts and stems without any issues
I have muckoff carbon paste in a tin, steel and aluminium frame stopping the droppers from slipping. So far so good
The best grip / friction paste I have had the pleasure to use - and I have tried quite a few over the years.
https://motorex.com/en-ch/carbon-paste--13360
"CARBON PASTE is ideal for mounting carbon and aluminium parts such as seat posts, pedals, handlebar stems etc. in the BIKE sector. This grease facilitates the dismantling of locked joints. The tightening torque required for the respective clamping therefore decreases by up to 30 per cent."
Does not damage the surface of parts like some pastes (Park Tool, krhm!) do. Works very well for both metal and carbon surfaces.
Is the post loose and a bit rattling in the seattube without a seat clamp on the frame, the seat tube may be oversized slightly, I don't rate hope seat clamps, Nukeproof ones have been perfect for me and never needed more than 3nm, a bit tight to get on though but I think that helps it clamp better.
Use carbon paste, it will be fine
Now is probably a good time to mention when I got a reverb stuck in a steel On One in about 6 months.
I had to take it to seat tube guy and he got it out using stage 1 of his three step process, but said he was on the verge of going to step 2.
Just my personal experience...
Thanks for all the replies, I have ordered myself a new post and some carbon paste, will see how it goes. If that doesn't work then I guess a different clamp will be next.
If it does work I will have to remember to take it out every so often so it doesn't get stuck in.
Try turning the clamp round so the bolt is on the other side of the tube than the cut in the seat tube
A longer dropper slammed to the frame?
Hope seat clamps are (in my opinion) terrible
Can one seat clamp actually perform better than another one? I thought they were basically just a bolt
Yeah, I've used Hope seat clamos on nearly every bike Ive ever had without issue.
Sounds loke OP has either a frame, post or clamp that's not to spec
Bird used to do a seat clamp collar that didn't have the full top lip that only exists to stop it sliding down the frame - it left only 3 small tabs to do this. This is meant to allow the collar to more evenly distribute pressure & might then grip a seat post in a way that doesn't make the dropper bind. It was some other company that make them for Bird - I don't recall who, but maybe they still make them. Anyway, I filed down one of my seat clamps like, leaving only 3 small tabs rather than buy one. :^D
On my other bikes I've got an XLC clamp that has 2 bolts like this:
https://www.amazon.co.uk/gp/product/B0035Z5U3O/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&th=1&psc=1
It isn't in stock right now, but it's good - if it fits the diameters you need. It might reappear.
It is for a frame external diameter of 34.9 mm, and internal diameter of 31.6mm
Edit: the big gap above is meant to be a link to amazon.co.uk, here's the end of the URL: amazon.co.uk/gp/product/B0035Z5U3O/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&th=1&psc=1