Cane CreekSeatpost Adapter Shim

For all the seat post sizes out there, shims can become very essential for riders that manage a number of cycles. Going to an e-bike, I used this to move a favorite seatpost / saddle to an e-bike of a larger frame size. This fit precisely, is well machined, light enough, and allowed me to use a much more comfortable seatpost.and saddle. Given that most posts synch at the top end of the seat tube, this provides good grip and has a well engineered lip to prevent it from slipping inside a normal undamaged tube.

Purchased to adapt my old specialized rockhopper to a modern seatpost size. Fit perfectly, doesn't let the seatpost slip. An awesome cane creek product as usual!

everything fits so precisely, there is no gap, everything is one piece. my original seat post didn't fit as well)I recommend it.

Precise fit and finish.

Simple part that isnt even seen when installed but a must have to accommodate common size seat-post. Star deducted b/c part was on back-order. At first told it would be an additional three-days but that was extended another 3-days. Almost cancelled after second delay but needed part and they had best price at Niagara. Not too bad of delay. Good product and seller.

OK, it's a shim. It fits and does what it needs to do. I wouldn't ordinarily take the time to review so basic a product, but the superior finish deserves a mention.I own Cane Creek shims in two sizes: 27.2 to 29.8 and 27.2 to 30.8. The reason is to use my Cane Creek 3G Thudbuster Long Travel Seatpost, 27.2 in my two bicycles. Too bad that 27.2 isn't a universal size.The machining on Cane Creek's shims is flawless. The black anodizing not only matches the Thudbuster, it has the same micro etching to hold grease. The silk screening won't last, of course, but it's also flawless.The thicker Cane Creek shims have an additional feature that goes beyond cosmetics. The shims have a half thickness groove opposite the compression slot. The groove is on the interior wall so it won't show up in the photos. It is the same width as the compression slot and runs the full length of the shim.My 30.8 OD shim has this groove, whereas my 29.8 OD does not. It makes a difference. I can squeeze the 30.8 shim closed with one hand, but not the thinner walled 29.8. The groove insures that you don't need to be Hercules to tighten your seat post clamp.The instructions call for applying grease to all four matching surfaces; i.e., the ID of the seat tube, the ID and OD of the shim, and the OD of the seat post. Less is better than more. The grease is only to prevent the surfaces from corroding together. If you apply too much, as I did, then the excess will have nowhere to go regardless of how much you tighten the seat clamp. The seat post will slowly squish down under load like a hydraulic piston.Made in the USA doesn't guarantee quality anymore, but it's nice to see when it does.

perfect sizing

I bought both the 27.2 to 31.4 and 27.2 to 31.6. I thought I needed the smaller one because my seat tube is a bit ovalized at the seatpost clamp area--but it was a bit too small to allow clamping with proper force. The 31.6 diameter worked perfectly. This is no reflection on the Cane Creek shim. For such a simple item, this is beautifully made: smooth on both sides; a pronounced lip on the top to it can't slip down into the seat post. A 3mm wide slit to allow compression around your seatpost, a 2.5mm wide groove opposite the slit to also allow some compression. It is quite long so it provides some grip for more than just the clamping area. I was using a carbon fiber seatpost so I used motorex non-abrasive carbon paste to prevent slipping. Didn't quite work with the 31.4; worked as expected with the proper 31.6 shim. Great solution.