Ridley Riddle

plumber77

Looking for some practical advice on removing a saddle post from the frame. Stuck in that position for a few years now. Anybody do something similar. Bike is carbon, seat post is aluminium as far as I know.

sullzz

plumber77 wrote: »

Looking for some practical advice on removing a saddle post from the frame. Stuck in that position for a few years now. Anybody do something similar. Bike is carbon, seat post is aluminium as far as I know.

I bought a carbon bike off one of the lads on here , the seat post was really badly stuck , i tried all the usual tricks , feeezing it and boiling water etc.
I eventually cut the seatpost half an inch above the frame and used a round file to file the seatpost out , it did take 9 hours to do but i really took care doing it .

plumber77

sullzz wrote: »

I bought a carbon bike off one of the lads on here , the seat post was really badly stuck , i tried all the usual tricks , feeezing it and boiling water etc.
I eventually cut the seatpost half an inch above the frame and used a round file to file the seatpost out , it did take 9 hours to do but i really took care doing it .

Cheers. Tried all that stuff too. Resigned to doing something similar now. Was hoping there might be one last tip out there

iwillhtfu

Before you cut it try drilling a hole through it then thread a strong screw driver or metal bar though the hole. It may give you enough leverage to twist the post free. Obviously drilling it lower just above the seat post clamp till give you the best chance of the post not buckling when force applied

Plastik

iwillhtfu wrote: »

Before you cut it try drilling a hole through it then thread a strong screw driver or metal bar though the hole. It may give you enough leverage to twist the post free. Obviously drilling it lower just above the seat post clamp till give you the best chance of the post not buckling when force applied

I did it like this previously. I clamped a long wheel brace/breaker bar into the saddle clamp and I was able to get the seatpost free.

TheBlaaMan

I think I'd be cautious with exerting too much force trying to lever out the post......you could damage the cf frame and that would be a shame. Better to take it slow and easy if it isn't budging....

Wishbone Ash

iwillhtfu wrote: »

Before you cut it try drilling a hole through it then thread a strong screw driver or metal bar though the hole. It may give you enough leverage to twist the post free. Obviously drilling it lower just above the seat post clamp till give you the best chance of the post not buckling when force applied

Would it not be easier to try to source someone with a bench vise and to turn the bike upside down with the seat post clamped in the vise and gently use the frame as leverage to loosen it?

iwillhtfu

Wishbone Ash wrote: »

Would it not be easier to try to source someone with a bench vise and to turn the bike upside down with the seat post clamped in the vise and gently use the frame as leverage to loosen it?

Possibly but it creates a lot more torque on the post and the frame the further you move away from the point it's stuck.

I don't think it would be a good idea to use the frame for leverage. It would be a great lever no doubt but perhaps to good. :eek:

magicbastarder

what expands more with heat - the carbon of the frame, or the aluminium of the post?

cython

iwillhtfu wrote: »

Possibly but it creates a lot more torque on the post and the frame the further you move away from the point it's stuck.

I don't think it would be a good idea to use the frame for leverage. It would be a great lever no doubt but perhaps to good. :eek:

Perhaps I'm missing something, but if you're using brute force and leverage, the frame is being used as a lever either way. Equal and opposite reactions and all that

So even if you use your screwdriver trick, the force(s) required to secure the frame to exert torque will still be exerted on the frame. Granted, you may not be able to exert as much force as with the bench vice approach (thus reducing the risk of frame damage), but if the post will come free with that, it should equally come free with the vice.

magicbastarder

to answer my own question, i found this:
http://www.christinedemerchant.com/carboncharacteristics.html

so aluminium expands far more when heated (i had been wondering was it the hot or cool end of the heating/cooling cycle when you'd expect most for the post to shift).

iwillhtfu

cython wrote: »

Perhaps I'm missing something, but if you're using brute force and leverage, the frame is being used as a lever either way. Equal and opposite reactions and all that

Perhaps I'm missing something!!!

Are we arguing the laws of physics here? ffs I gave my opinion on the approach I would take by all means do otherwise. :rolleyes:

koutoubia

Happened me a few years back. 360 cycles in Clontarf got it out for me. They have some sort of expandable drill bit and drilled out the post. Frame looked perfect!

Zynks

A mechanic friend of mine, when something gets badly stuck, always puts a bit of oil, waits a few minutes and then forces things in the opposite direction he wants them to go. Once he gets some movement then he forces it in the wanted direction whether it is a nut, a piston or whatever. I know it sounds counter-intuitive, but it seems to works every time.

Cee-Jay-Cee

Zynks wrote: »

A mechanic friend of mine, when something gets badly stuck, always puts a bit of oil, waits a few minutes and then forces things in the opposite direction he wants them to go. Once he gets some movement then he forces it in the wanted direction whether it is a nut, a piston or whatever. I know it sounds counter-intuitive, but it seems to works every time.

That's fine when it's metal in metal and will not break it deform whatever it's inserted into but doesn't really work for soft slloy in a carbon frame although I would try tapping it downwards to see if the seal will break but you need to be sure to hit it squarely so as not to break the seat tube. Worth a try!