Bicycle Seat Post Slippage
If your seat drops in the middle of a rather tricky trail, I can
tell you that you'll not be a happy rider... it can throw off your
balance and end in a messy crash. Most often it is caused by not
getting the right bike part in the first place....
Possible Cause #1:
- bicycle seatpost diameter is not the correct size to match your
Seat posts come in a
huge array of sizes, especially because today there are so many
manufacturers around the world inflicting their own sizes as standard.
As well, mountain bike tubes are not exactly the same as a road
bike tube. Although the sizes are similar, the diameters are fractionally
It is important to do the research on your frame and find the manufacturer's
recommendation and then get the right sized seat post for your frame.
It may be that your local shop has either the frame manual or the
tools to accurately measure and recommend the pipe necessary for
your bike frame.
Possible Cause #2:
If you have tightened the seat post clamp as tight as it will go
and the seat post is still moving, check to see if the split ring
in the clamp is bottoming out (ie. completely closed). If this is
the case then it could be that you have a clamp that is too big
for your seat tube.
If you over torque the clamp you could end up distorting the shape
of the seat tube, snapping the quick release lever or stripping
the thread on the clamp. Excessive tensioning should not be necessary.
If you get stranded along the trail, and the seat post will just
not stay in place it is possible to remove the post, wipe off any
grease on the stem and roll it in a bit of mud. Wipe off the excess
and replace it in the tube. This should give you enough traction
to get you home.
When you get back to the garage, be sure to remove and clean the
post or any residual moisture will encourage corrosion.