Get a seat post to stop slipping

[93EXCivic]

Ok so my Schwinn High Plains townie is having problems with the seat post staying. I have a 25.4mm seat post with a 26.4mm cane creek shim in it with a seat post binder bolt rather then a QR. It just will not stop slipping. I made sure the clamping slot in the seat tube was clean and not touching. I have cleaned and greased inside the seat tube. I am fairly sure 26.4mm is the right size. Should I put carbon paste between the shim and the post?

Sent from my LM-G820 using Tapatalk

 

[Couch tater]

Put a split collar clamp on the post where it enters the seat tube. Works for me.

 

[us56456712]

What is a crane creek shim made from. I have luck with soft aluminum shims that the binder can really bight into. Plastic ones are iffy.

 

[93EXCivic]

What is a crane creek shim made from. I have luck with soft aluminum shims that the binder can really bight into. Plastic ones are iffy.

It is aluminum.

Sent from my LM-G820 using Tapatalk

 

[pebblewurm]

Beer can to the rescue!

 

[Duchess]

Way I solved the issue on Interrobang was to use grade 8 hardware on the (steel) binder clamp as the stock hardware was way too weak. Problem in my case was that I needed a long seat stem for my height and the only 13/16" I could find was a cheap Wald one that would bend with the necessary free length. To fix that, I hammered an aluminum rod into it. That certainly made it stiff enough, but then the seat clamp wouldn't hold it because it was too stiff to flex with the force the stock hardware could impart.

 

[93EXCivic]

Looks like it is time to make a McMaster Carr order

Sent from my LM-G820 using Tapatalk

 

[RustySprockets]

If you haven't already done so, liberally lubricate the threads on the clamping hardware. Seriously! It makes a big difference. You want the clamping force focused at the seatpost, so eliminate friction everywhere else.

 

[AndyA]

I am fairly sure 26.4mm is the right size.

Like the Tracy Morgan ad on the Super Bowl, "pretty sure" might not be enough. Seat posts come in lots of sizes, some only 1mm different. Time to buy a vernier caliper (or a digital caliper if you want to spend more money).

 

[93EXCivic]

Like the Tracy Morgan ad on the Super Bowl, "pretty sure" might not be enough. Seat posts come in lots of sizes, some only 1mm different. Time to buy a vernier caliper (or a digital caliper if you want to spend more money).

I tried out a bunch of sizes shims and this fits the best. Also I did measure it with a caliper.

Sent from my LM-G820 using Tapatalk