MrWasabi

I just got a new Niner RDO carbon seatpost and am installing it on my Fuji Traverse. Should I get some carbon paste? I’ve been reading that it’s a good idea to avoid slippage later? What’s a good brand? I saw some reports that the Park Tool paste may be too gritty and scratch? Also, am I OK with any steel/aluminum collar/clamp as long as I tighten it to spec?

Thanks for any input.

Unca_Sam

Use a carbon paste of your choosing. The Park grip gel is indeed a little gritty for tight fits. The benefit to using a grip paste is that you don't need to tighten to max spec to prevent movement. I use the stuff on slippery alloy/alloy interfaces as well, like quill stem handlebar clamps.

MrWasabi

Thanks for the input,

I’ll pick some up. Thinking about this Finish Line:
https://www.amazon.com/dp/B0012RIEM6...ing=UTF8&psc=1

blacknbluebikes 

I don't bother with paste. Never needed it. torque to 5nM and go.

Unca_Sam

As always, YMMV.

I've had greased alloy posts slip in steel frames with the clamp bolts tightened to 50 in/lbs slip.

veganbikes

I use paste personally whenever coming across carbon but that is me. Park Tool is probably fine but I believe in past uses I used Fiber Grip from Finish Line. Make sure to use a good torque wrench most importantly.

Badger6

Always tighten to recommended torque. And, yes, use paste.

Terrible advice. Use paste. Carbon will slip. Also, random torque specs from the internet are dangerous...too loose, too tight, probably not right....torque to the manufacturers spec. Always.

MrWasabi

Thanks again for the great input everyone,

Do I just apply a light coat of carbon paste inside the seat tube about an inch or so in before I slide the seatpost in?

SoSmellyAir

That is basically it, at least for bikes that use an external seat post clamp like the Fuji Traverse.

blacknbluebikes 

I guess over 20,000 miles on two different bikes is an anomaly. Lucky me.

Badger6

Reminds me of something someone once said to me: "Better to be lucky than good." All jokes aside, you are indeed either lucky, or lucky that your 5Nm is the correct torque spec for your binder and seat post. I've got a couple of bikes (combined) with somewhere north of 100,000km with carbon seat posts, and all 5 of them have slightly different torque specs, and when I wing it, even with paste, the posts tend to fall a bit. I guess I am not lucky. As an aside, not one has a recommended torque under 6Nm.

So to you good madam or sir, a tip of the hat and a glass raised to you, because you aren't wasting time with paste and a torque wrench.

Again, OP, use paste and follow the recommended torque specs. We aren't all this lucky.

Andrew R Stewart 

Not mentioned is the galvanic corrosion aspects of carbon posts in many frame materials. Some sort of assembly coating (paste, grease, anti seize) to make removal possible after a year of neglect is strongly suggested. As to tightening torque- I've been told by a number of people smarter then I am that the torque specs for bike parts are generally the MAX and not the MUST DO levels. If a bit less then the listed spec works, the post stays put in use, then there's no reason to max the tightness out (and some why less but good enough can be better). Andy

Sy Reene

+1 . I've often understood that the torque rating is simply what the manufacturer is saying what their bolt (material and thread size) can withstand without stripping. A seatpost clamp maker, has no idea what material seatpost you're actually going to use, or how it was made (unless it's some proprietary shape where you have to use a specific brand/model seatpost), nor the rider's weight, and therefore has no idea what the seatpost itself can withstand or what's required to avoid slippage.