Aagra1207

Hello All

I have super six evo 105 disc which is carbon frame but post is aluminium. Today when I went on ride the seat kept sliding down when I check after couple of miles. I am hesitant to tight too much due to horror stories of carbon cracking due to over tighten. However as I said although bike frame is carbon but sliding clamp which holds the seat post in place and the seat post itself is alloy(not sure if sliding clamp is rubber or metal). so is it still the same risk of cracking carbon frame off tighten it more than 6nm? Rating there is 6 nm but not sure how to check that without a torque wrench.. have ordered the wrench but it will take two week to come.. attaching the pic

veganbikes

Make sure you are using carbon paste on the seatpost and torque it properly using a quality known quantity torque wrench. There really isn't a good substitute for that. A lot of mechanics claim to be able to know torque from years of doing it but that is certainly hooey. Certainly they can get something tight but won't necessarily get it to proper torque specs and that is the key with crabons.

If you are truly having issues take it to your local shop and have them take a look at it.

Aagra1207

. But does it not matter if seat post is alloy or carbon? I totally agree if seat post is also carbon then it will crack if you over tighten.. but confused if seat post is alloy?

cxwrench

Tighten to 6nm. Use carbon paste. Do not concern yourself w/ materials. If it slips after ACCURATELY tightening to the specified torque take it to your local Cannondale dealer. I'm not even sure why you're posting this question if you don't have a torque wrench.
ETA: This should be posted in 'bicycle mechanics'.

kahn

But the seat tube might be carbon under the clamp???? I agree with the bike shop visit.

biker128pedal

Sounds like you need a torque wrench. Found these on a motorcycle forum recently.

https://www.prestacycle.com/product-category/torque-tools/
Amazon has these too.

I have an old Madone with a carbon seat post. I found if I cleaned the seat tube and post well with isopropyl alcohol it does not slip. When I first bought it new it slipped and I found a lube or may be paste was used. So I’d clean it first. Once a year I do a good cleaning and pull the post.

KJ43

This is what needs to be done. If you check the SuperSix Evo manual available on Cannondale's website that is exactly what Cannondale directs you to to as well.

Get a torque wrench. I recommend getting couple of torque wrenches for a range of torque specs, but the Park ATD 1.2 is a good tool for the most common settings at the seatpost collar and stem bolts.

The carbon paste will give you really good friction and if you are really paranoid may allow you to go a bit lower on the recommended torque and still give a very solid grip.

Koyote

There is no point to this thread until the OP ensures that the torque is as specified.

Iride01 

If nothing else just tighten it a little more each time until it stops slipping. No torque wrench required using that technique.

Aagra1207

Thx ...i have ordered the carbon paste so will try it today...maybe will first clean with alcohol and then apply paste? As far as Torque wrench goes, I have ordered but it is coming from UK and I am in Canada so may take some time...in LBS the wrench were very costly

Aagra1207

Yes i have ordered the wrench but it might take some time to arrive...so meanwhile I was just wondering if alloy seatpost in carbon bike frame are equally vulnerable like carbon seatpost....I will anyways try the carbon paste until then...

Sy Reene

One of these is always handy around the house. 5Nm is a pretty useful value on bike bits. 6Nm.. means you just tighten a tiny bit more :-)

Barry2 

+1 on using Carbon Assembly Paste

on a side note…….
It always beats me why people don’t state their location!
I’d meet you at a local park and place a torque wrench in your hand for 5mins.

Barry

Aagra1207

i am in north York Ontario Canada..😊

biker128pedal

There are some Lowe’s stores in the Toronto area or other hardware or auto parts store. Look for a 1/4 inch drive torque wrench. At the low end it will do. You may have to convert units.

Aagra1207

for now I picked one from Canadian tire.. it is digital torque wrench but insanely costly…$200 with taxes.. also this wrench was made in 2018 .. god knows if it is calibrated

veganbikes

I wish I had known about this before I got my Park Tool ATD 1: https://mbaction.com/product-testing...torque-wrench/
I may sell the Park one and get that one, they are owned by Snap-On currently and are supposed to be quite reliable from what I understand. Really the main thing is the ATD 1 requires a tool to adjust the ATD 1.2 doesn't but in the end the CDI one has a few more settings from 2-8nm which covers most of my day to day needs (wish it did 1nm but I so rarely need that) but than I might end up with a Snap-On or CDI digital torque wrench and then maybe I won't need much more because they are so nice to use.

I think for most mechanics at home the smaller ones will do fine for seat posts, handlebars, accessories and smaller bolts. You won't get things like crank bolts or Hollowtech II bolts and things like that but 2-8 is a decent enough spread and that tool is not super expensive considering it is calibrated with certificate and isn't so big.