Rock Lobster Ti Seatpost size

Stu 74

Just bought a Rock Lobster Titanium frame from Merlin.

According to this...

http://www.marchini.co.uk/Rock%20Lobste ... ometry.pdf

the seatpost size is 27.2mm.

However, my 27.2mm seatpost feels a bit loose in the seat tube and I really have to wind the seapost clamp tight to keep it in place.

Have measured the seatpost with calipers and it is 27.2mm but the seat tube measures 27.3mm.

Is it normal for the seattube to be slightly bigger than the seatpost (i.e 0.1mm)?

Have shimmed it with insulation tape for now.

Can any Rock Lobster Ti owners help please?

Thanks

Stu

andyg1966

Sounds OK to me, I've got a Ti Rock Lobster same as you with a Thomson 27.2 seat post and hope clamp. Yes its not tight but doesn't slip down.

Stu 74

Thanks for the reply Andy.

Have spoken to Merlin who confirmed that it is 27.2mm.

How much does the gap at the top of the seattube get squeeze in when you tighten up the seat clamp?

Many thanks

Stu

delcol

my santacruz heckler was like that had the correct seatpost for the frame but it would always drop gradually when riding no matter how tight the clamp was (oem santacruz clamp) try cutting a coke can and shimming it, worked for me. until i replaced the seatclamp with a chromag one i didnt need to shim the post to stop it dropping with this seatclamp..

my santacruz butcher is fine though..

tomwood1981

I had exactly the same problem with my Rock Lobster team ti (2010). Merlin confirmed it was 27.2mm but I always had trouble with it either slipping or requiring my (Hope) seatclamp to be excessively tight to the point I was worried the bolt would break. It never did, which I suppose is a testament to Hope.
After 20 months of riding, some cracks have appeared in the welds on my head-tube so it's game over for my team ti. Keep an eye on your RL ti frames! They only have a 2 year warranty.
I wont be buying ti again after this experience. Although the RL is a "cheap" option, it still cost more than steel or alu and the main advantage I hoped for (a lifetime of service) has not been borne out.