Hi, i'm putting together a Schwinn Super Sport with an aluminum frame and using a carbon post. Don't have access to carbon paste, so what else can I use? Grease? Vasiline? Dry? I don't want to scratch the post or have some of type of chemical reaction ruin it. Will be posting project pictures in C&V as the bike is old but carbon questions don't go in C&V. Thanks in advance.

Bump, help?

I don't know what to tell you on the grease, but the chemical reaction worry is more for different metals. The epoxy resin resin used in your seatpost should be fairly inert.

A bump after only 40 minutes? Is that a record?

When using an aluminum frame and a carbon post I don't use anything.

Thanks, I just needed an answer for what I thought was a simple question. I hear a lot about having to use paste when putting posts in cabon frames. Second I hear about all the things done wrong with cabon parts that leeds to a failure, over torque, chemicals that soften the resin. Never had a carbon part untill i bought a carbon fork, now i'm sold. So now I have a seat post and don't want to do it wrong. Thank you.

The paste just allows less torque than the rated number for the post. Otherwise, there should be plenty of grip if you torque to within specs. GL

i thought it also prevented seatpost seizing/bonding, especially with a carbon post in an aluminum frame. is that incorrect?

hope you were kidding about the vaseline

The point of carbon paste isn't to decrease friction. it's there to INCREASE friction. that's why it's granular.

you put it on there so the parts have some more grab, so they don't require as much torque to keep in place, so you don't risk over-torquing the bolts and damaging the carbon.

alu frame an carbon post you shouldnt need carbon paste. it does help though when you have carbon on carbon for the reasons mention above.

A pro team mechanic told me they use a mixture of grease and talc.

I have a hard time believing that neither Bicycle John's nor Gil's (your two local shops) don't have carbon paste. Even if they don't have it, there are tons of places on the internet that sell it. Or maybe this is a case of not wanting to wait any longer to put it together?

Having said that, you're probably OK with a carbon post in an aluminum frame since over-torquing a seatpost clamp has a much lower potential for frame damage on a non-carbon frame.

We have Bicycle Johns, Love the place, also The Block Shop. I was hoping to use something in the garage. I have pipe thread compound, it gives grip and still allows the parts to be removed. I did not know that carbon paste was for grip. For years used grease with steel frames and steel or aluminum posts. I'll check to see that the pipe compound doesn't contain solvents. Thanks.

You probably know more than me on that front. I've never had it happen.

Hairspray works well.

well, my carbon seatpost is stuck in my aluminum frame, and the frame builder said he used a paste...
he said that I should have taken the post out every so often to clean it...i didn't know about that...
live and learn, i guess...it also happend to someone else in my club...so take care with your carbon/aluminum set-up
good luck

toothpaste..? I wouldn't use a grease as at sometime it will eventually contaminate the epoxy resin and cause the post to fail.

Have you tried dripping something with ammonia down the seat-tube? I'm not sure if the epoxy has glued itself onto the seat-tube or maybe the aluminum oxidized.. if the latter try some windex.

nah, but I did read an artlce by Leonard Zinn on velonews.com...
sounded like a lot of work to get it free...the other guiy in my club
was told to "crack" the post and just chip the rest out...I just bought
another frame (@$500 why not?) and new seatpost (carbon) lol
but I might see if that works--after I ask around a bit
thanks

new frame & seatpost:

[/QUOTE]

Please tell us more about that frame, I didn't see any bare frames for sale at the Sampson site.

The Blue and Chrome is pretty sharp!

it's an older design..it's a "Ciao." lol
i dont know all the angles, but it's a 1" steerer
mine is built with Dura Ace 7800 and Easton wheels
weighs just over 19lbs. Here are some reviews for it.
Just ask Eric about it, you might be able to get a
really good deal--I paid a lil x-tra for the paint job.
btw, it's not chrome. my 1st "race" bike (a Scapin) had
chrom stays--the stays on this bike are just unpainted.

this is the bike with the stuck seatpost:

^^^ This.

When I had a carbon post in my carbon frame it slipped all the time unless I had paste in there and then even sometimes then. When I went to a Fizik Cyrano Al post (fantastic seat post, check it out) all the problems went away no paste needed.

J.

Well, getting medieval on it may be an option. Vise-grips and rotating the seat post or saw it off and use a steel tube with the same OD to hammer the carbon down into the seat-tube. If the frame is just lying around...

I have an aluminum frame and the aluminum cyrano post, and I have had to resort to carbon paste to keep the post in place. I weigh 160, so it's not like I am terribly heavy. I have never had a post that requires me to bust a proverbial nut to keep it in place and keep it from creaking.

https://www.parktool.com/blog/repair-...osts-and-stems

this is what i was thinking of...from the second paragraph in the link above:

"When inserting an aluminum post into a carbon frame, it is important to apply a barrier between the two surfaces. This is also true when installing a carbon post into a steel or aluminum frame. A 'galvanic reaction' occurs between the two different materials and this acts to eventually bond the post to the frame. Use a light coating of grease, anti-seize, or other lubricant to create a barrier between the two surfaces."

i guess i was mistaken in the sense that carbon paste is more for friction (and maybe just for carbon on carbon??), but it seems like the important thing is to get something in there to prevent bonding.

That doesn't seem right. Are you sure there is no grease or lubricant in the seat tube?

At least when I went to an AL seatpost in my carbon frame, all the slipping stopped.

J.