My P3c seat clamp (06 model) rotated saddle-nose down AGAIN during a race on bumpy roads. It was torqued to Cervelo spec of 12 NM. Cervelo tech mentioned in an email about something about a “friction compound” - goes on like grease but adds friction. Anyone have a clue what product they are referring to? I will ask them as well but it often takes several days to get a reply, and I have a race this weekend.
Carbon assembly paste. A good LBS will have some and you’ll only need a little bit.
Do you ride with the saddle pushed forward? I am borrowing a Cervelo right now and had the same problem you described. The seat tube is too slack for me, but with a long saddle pushed all the way forward I can get in front of the bottom bracket a few centimeters. And then it slips when you hit a bump. The once race I tried it, I ended up at 73cm above the bb when I started at 75cm.
Chad
Yes- it’s slammed all the forward and I still ride towards the nose - plus I am 200 lbs. It dropped about 2cm on me as well. It only happens when it is good and bumpy. Looks like the 07 seat clamp is further forward - anyone know if it is? I assume it fits the 06 frame.
I’m only 150 lbs and mine slips as well. The clamp design seems pretty clever until you find yourself riding nose down unintentionally. If the seat tube was a little steeper you could get the saddle in the middle of the rails, but I would estimate the angle somewhere between 76-78 which I think is the shallow end of usefullness in triathlon.
Another question for you–what size is your frame and how far forward can you get the saddle in front of the bb?
Chad
I had a P2C and the seat slipped down as well. I didn’t try the paste, though.
There are a couple good seat post head designs out there. But Cervelo’s doesn’t seem to be the most user-friendly.
I have had the same problem since I bought my P2C, Mission Bay has been great about replacing it but I am now on Seat Post #4 in a year! This time my they epoxied it in place but its slipping again!
Make sure you tighten it down on both sides (ie two allen wrenches). Tightening from only one side will not do the trick. You are talking about the clamp for the saddle, right? Not the actual seatpost?
Yes - clamp for saddle. I do use two wrenches, and greased the screw so that it wouldn’t bind and give false torque readings. I will try to call Cervelo about this tomorrow. I don’t think the carbon assembly paste is the right stuff - that may work on the post where it goes into the frame, but the edges of the hole in the seatpost and the clamp itself are metal.
I ride a 61 cm, and my saddle nose is 1-2cm ahead of the bb when jammed forward. A buddy of mine rides a 54 and he would like to get his more forward as well. That is why I am wondering if the 07 post has the clamp more forward (since it has the forward projecting “lobe”)
Hello Ttbikefit and All,
IIRC I saw some pics of TdF Cervélo bikes utilizing both seat clamps but the seat was not full forward.
For a full forward seat you could use a second seat clamp and a small aluminum L bend rod attached from the second seat clamp to your seat rails if all else fails.
My P3C seat clamp slipped too but my LBS tightend it until I thought the bolt would explode and it fixed it.
He said the bolt would fail before the carbon fiber seat post would be damaged because of the design of the seat clamp.
So when I adjust the seat now I tighten the seat clamp VERY tight, and you need a wrench on each side to do it.
Also there are some ‘liquid sandpaper’ products that will help improve the friction in the seat clamp.
Cheers,
Neal
You ride a 61? You must be huge! I think I am on a 56, and I am just shy of 6’2’'. Anyway, the tip of my saddle is ~3cm in front of the BB, so I can relate. I used to have this same issue, then I was able to fix it by simply ensuring it was super tight. I had this problem on the original (2005) version, and I fixed it by over-tightening. I now have the newer version of the seatpost, and I have never had the same problem. Not sure if it is because of the design or if I just tightened correctly the first time with this one…
I think I found the mystical “friction compound”:
Located this on the Cervelo website forum - there is also an FSA-branded version of the same stuff, which is called “Installation compound”.
So Cdanrun, I stand corrected, I think you were right!!
Yes I am on the large side at 6’4"+
More info: I found a post by Gerard in the Cervelo forum stating that once it has slipped a few times it may be hosed (serrations damaged). He suggests the aforementioned paste (there is also a Tacx version) or even loctite.
email Ian at fitwerx and ask him.