Seat post slides down
#1
Senior Member
Thread Starter
Seat post slides down
I have a seatpost that keeps sliding down and I got someone to have a look at it last week. A free bike mechanic. They put degreaser on it and the solution seem to work for a bit but then started sliding again. No matter how tight I try and clampit it makes really no difference. It's just seems to have gotten worse in the last 6 months. I have it held up at the moment with some items that were in my bike related box if you will and it seems to be working for now. I don't know if it's good solution but someone reading this might have a better solution than this
Likes For cat0020:
#3
Schwinnasaur
Check to see that the seat tube itself and the clamp is not damaged or cracked. If nothing seems wrong, you can make a secondary clamp from a quick release clamp. I had to do this for my Brompton. This one is made from a seatpost quick release post. I had to file away the lip on the clamp to make it work.
Likes For Schwinnsta:
#4
Senior Member
Thread Starter
#5
Senior Member
Thread Starter
Check to see that the seat tube itself and the clamp is not damaged or cracked. If nothing seems wrong, you can make a secondary clamp from a quick release clamp. I had to do this for my Brompton. This one is made from a seatpost quick release post. I had to file away the lip on the clamp to make it work.
#8
Schwinnasaur
Yes there is seatpost clamp on yours already. You would add one like the one I linked too but you would have to modify a bit. If you look carefully at it there is a lip on the inner edge. That lip needs to be filed down.
#9
Senior Member
Thread Starter
sorry i dont get it. So i would have 2 exactly the same? i dont see where or how. i honestly have no idea what a lip is on this
#10
Schwinnasaur
No, the original one clamps around the seat tube and forces the seat tube to pinch the seatpost. The additional one goes around the seatpost only, and prevents it from slipping down. There is a video of this made by a forum member and posted on the forum somewhere.
#11
Senior Member
Thread Starter
not with mine. i only have one clamp or quick release
#12
Schwinnasaur
You have to buy the second one. Sorry, I can not explain it better. You buy the second one like the one I linked too for your diameter seatpost. Then you modify it by filing off the lip. Then you install it. Then your seatpost won't slip anymore.
#13
Senior Member
Thread Starter
oh ok i cant see where to place it. the first one is the right size. hmmmm i dont know what to do. i guess it will have to be a mystery. sorry i just dont get it. maybe my photo is misleading because of all the things i have on the seatpost. maybe thats the reason
#14
Half way there
Join Date: Sep 2015
Location: North Carolina
Posts: 2,957
Bikes: Many, and the list changes frequently
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 986 Post(s)
Liked 880 Times
in
527 Posts
Oh, I took another look. It appears that you added all of that junk to serve as spacers between the top of the seat tube and the bottom of that trailer hitch you have clamped onto the post. My bet is that you have a crack in your post clamp. It's small enough so it is not apparent when released, yet opens up slightly when clamped so that it's less than functional. A new clamp will probably do the trick. Also, we routinely grease seatposts before installation so that they don't corrode and stick in the tube. This grease does not affect positive clamping if the clamp is good.
Likes For Moe Zhoost:
#15
Senior Member
Join Date: Aug 2010
Location: Madison, WI
Posts: 11,203
Bikes: 1961 Ideor, 1966 Perfekt 3 Speed AB Hub, 1994 Bridgestone MB-6, 2006 Airnimal Joey, 2009 Thorn Sherpa, 2013 Thorn Nomad MkII, 2015 VO Pass Hunter, 2017 Lynskey Backroad, 2017 Raleigh Gran Prix, 1980s Bianchi Mixte on a trainer. Others are now gone.
Mentioned: 48 Post(s)
Tagged: 0 Thread(s)
Quoted: 3459 Post(s)
Liked 1,465 Times
in
1,143 Posts
I had a seatpost (painted black) that was slightly undersize, kept sliding down. Got tired of that, so I cleaned off the grease and masked off the part of the post above where the post went into the frame. Then sprayed a few thick layers of black spray paint onto the post. Let the paint dry and harden sitting outside for about a week where it was in the sun during the day. Then put it in the bike. The extra thickness of about three layers of spray paint was enough to make it slightly bigger and quite slipping.
Likes For Tourist in MSN:
#16
Schwinnasaur
Likes For Schwinnsta:
#17
55+ Club,...
Join Date: Aug 2012
Location: Somewhere in New York, NY
Posts: 4,322
Bikes: 9+,...
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 1112 Post(s)
Liked 847 Times
in
591 Posts
All anyone is saying is add another quick release to the seatpost stem, so the seatpost can't slide further down onto the frame. You'll have 2 quick release clamps (1 on the bike, and ANOTHER on the seatpost stem itself), and it should solve the problem.
__________________
If it wasn't for you meddling kids,...
#18
Senior Member
Thread Starter
this is it without all the stuff
Bingo! It's hard to figure out what's what in that photo. Could you strip off the stuff that is irrelevant and take additional pictures?
Oh, I took another look. It appears that you added all of that junk to serve as spacers between the top of the seat tube and the bottom of that trailer hitch you have clamped onto the post. My bet is that you have a crack in your post clamp. It's small enough so it is not apparent when released, yet opens up slightly when clamped so that it's less than functional. A new clamp will probably do the trick. Also, we routinely grease seatposts before installation so that they don't corrode and stick in the tube. This grease does not affect positive clamping if the clamp is good.
Oh, I took another look. It appears that you added all of that junk to serve as spacers between the top of the seat tube and the bottom of that trailer hitch you have clamped onto the post. My bet is that you have a crack in your post clamp. It's small enough so it is not apparent when released, yet opens up slightly when clamped so that it's less than functional. A new clamp will probably do the trick. Also, we routinely grease seatposts before installation so that they don't corrode and stick in the tube. This grease does not affect positive clamping if the clamp is good.
#19
Senior Member
Thread Starter
#21
Senior Member
Thread Starter
I had a seatpost (painted black) that was slightly undersize, kept sliding down. Got tired of that, so I cleaned off the grease and masked off the part of the post above where the post went into the frame. Then sprayed a few thick layers of black spray paint onto the post. Let the paint dry and harden sitting outside for about a week where it was in the sun during the day. Then put it in the bike. The extra thickness of about three layers of spray paint was enough to make it slightly bigger and quite slipping.
#22
Senior Member
Thread Starter
So seems if i get the 31.8mm one it will do the job? https://www.aliexpress.com/item/4001...apt=4itemAdapt
#23
Schwinnasaur
So seems if i get the 31.8mm one it will do the job? https://www.aliexpress.com/item/4001...apt=4itemAdapt
#24
Senior Member
Thread Starter
oh sorry forgot to mention the measurement. 27.4mm. so seems right. yeah i have had things take anything up to 6 months from them but mostly under 3 months . lately tho(i think they now have a warehouse in australia or some of the sellers are here) i have been getting things within 2 weeks. local bike stores are so over priced and often dont have anything to sell except a very limited amount of seats, bells....well just super limited. i have never been able to source anything from them that i have asked for in over 10 years
#25
Schwinnasaur
oh sorry forgot to mention the measurement. 27.4mm. so seems right. yeah i have had things take anything up to 6 months from them but mostly under 3 months . lately tho(i think they now have a warehouse in australia or some of the sellers are here) i have been getting things within 2 weeks. local bike stores are so over priced and often dont have anything to sell except a very limited amount of seats, bells....well just super limited. i have never been able to source anything from them that i have asked for in over 10 years