How much steerer tube do i need?

Question

How much of the steerer tube on the bike forks needs to come out of the top of the steerer tube on the bike?

Answer 1

Don't cut your steerer before you are absolutely positive you are completely comfortable with the bar height.

Answer 2

As Bob A says, the steering tube needs to be long enough to get the handlebar stem mounted.  Remember, the top of the steering tube needs to be below the top of the handlebar stem so the cap bolt will properly tighten.  An eighth to a quarter inch is good.  If the steering tube is above the top of the stem you won't be able to tighten the cap bolt down.

You may also want to be able to put some spacers below the stem to raise the handlebars to a comfortable height.  Thus, your steering tube may need to be a bit longer.  In any case, you don't want more than one inch of spacers.  (If you have a carbon steering tube, you may not be able to have even one inch of spacers.)  Too many spacers will make the steering column flexible and sloppy.

Here is more information on the Parktool Website:

http://parktool.com/repair/readhowto.asp...

Hope this helps.

Answer 3

enough for the stem and 2 additional spacers 10 mm each

Answer 4

Enough to get the stem on or longer, you need spacers the take up the extra height.  Bike shops will have what you need.