Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 05-20-11, 12:50 PM   #1
common man
Senior Member
Thread Starter
 
Join Date: Jul 2009
Bikes:
Posts: 309
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
400 mm seat post on 17.5" frame: too much insertion into frame?

i borrowed a relatives' trek 17.5" frame and used a 400 mm seat post to make it fit me. now i am returning it to him so he doesn't need the extra height of the seat post. however, we lost the original seat post.

question: a 400 mm seat post will have extra insertion into the frame - can this damage the frame?

we more commonly hear minimum insertion but is there such a thing as "maximum insertion?"

thanks
common man is offline   Reply With Quote
Old 05-20-11, 02:25 PM   #2
bikeman715
Senior Member
 
bikeman715's Avatar
 
Join Date: Mar 2008
Location: Salinas , Ca.
Bikes: Bike Nashbar AL-1 ,Raligh M50 , Schwinn Traveler , and others
Posts: 2,416
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
no such thing as "maximum insertion " . but depending on the frame tube built and / or if there waterbottle cage 's bolt in the way to keep the post from going all the way down .
bikeman715 is offline   Reply With Quote
Old 05-20-11, 02:33 PM   #3
zzyzx_xyzzy
headtube.
 
zzyzx_xyzzy's Avatar
 
Join Date: Sep 2008
Bikes:
Posts: 804
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Can't think of a way it would hurt anything; it might not go in all the way if it hits a bottle boss or something. Deeply inserted posts can be a source of mysterious once-per-crank-revolution clicking noises and can retain water, so just grease up the end of the seat post before putting it in.

You can also just take a hacksaw and cut it down, as long as enough remains below the top of the seat tube -- if the min insert line is 4" from the end, say, you can cut it down as long as you're putting at least 4" of shortened post in the seat tube.
zzyzx_xyzzy is offline   Reply With Quote
Old 05-20-11, 03:18 PM   #4
common man
Senior Member
Thread Starter
 
Join Date: Jul 2009
Bikes:
Posts: 309
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
edit: thanks guys you were right - it is hitting the water bottle bolt. didn't realize this before. will have lbs hack saw it or buy a cheap seat post and keep the 400mm as spare.

Last edited by common man; 05-20-11 at 05:07 PM.
common man is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 10:50 AM.