Steerer too long

dannyfrankszzz

I'm currently in the process of replacing my front forks.

The steerer tube I have is slightly too long by about a 10-20mm. No bother I thought - I'll just leave it, and place the stem clamp over the steerer and leave the excess 10-20mm of space between the top of the stem clamp and the top cap.

However, when I lift the front of the bike up, the steerer is loose inside the head tube (lateral movement), which I assume is because of the excess length on the end of the steerer.

So I guess the top cap fastens the stem clamp and steerer into the headset??although I'm not exactly sure how.

I had fastened the stem clamp just above the headset, which I thought would be sufficient securing of the steerer - if you know what I mean.

I suppose I should just go ahead and saw off 2cm from the steerer tube, but I'm hesitant.

Simonb

dannyfrankszzz wrote:

> The steerer tube I have is slightly too long by about a
> 10-20mm. No bother I thought - I'll just leave it, and
> place the stem clamp over the steerer and leave the excess
> 10-20mm of space between the top of the stem clamp and the
> top cap.

You need to build up the difference using spacers, so that
when you tighten the cap, it pushes the stack (stem and
spacers) down onto the headset. It's designed so that hedset
tightness is adjusted using the cap. Once you have that set
up, tighten the stem bolts and you're away.

> However, when I lift the front of the bike up, the steerer
> is loose inside the head tube (lateral movement), which I
> assume is because of the excess length on the end of the
> steerer.

Yup.

> So I guess the top cap fastens the stem clamp and steerer
> into the headset??although I'm not exactly sure how.

Ah. Have you installed a star nut in the steerer?

> I had fastened the stem clamp just above the headset,
> which I thought would be sufficient securing of the
> steerer - if you know what I mean.

You will not get the right load (vertical) on the headset to
achieve this by tightening the stem alone.

> I suppose I should just go ahead and saw off 2cm from the
> steerer tube, but I'm hesitant.

Wait. Till you're sure you know what you're doing.

Richard Goodman

"dannyfrankszzz" <usenet-forum@cyclingforums.com> wrote in message
news:jgDIc.58332$F72.34831@fe06.usenetserver.com...
> I'm currently in the process of replacing my front forks.
>
> The steerer tube I have is slightly too long by about a
> 10-20mm. No bother I thought - I'll just leave it, and
> place the stem clamp over the steerer and leave the excess
> 10-20mm of space between the top of the stem clamp and the
> top cap.
>
> However, when I lift the front of the bike up, the steerer
> is loose inside the head tube (lateral movement), which I
> assume is because of the excess length on the end of the
> steerer.
>
> So I guess the top cap fastens the stem clamp and steerer
> into the headset??although I'm not exactly sure how.
>
> I had fastened the stem clamp just above the headset,
> which I thought would be sufficient securing of the
> steerer - if you know what I mean.
>
> I suppose I should just go ahead and saw off 2cm from the
> steerer tube, but I'm hesitant.
>

The top cap is used to pre-load the steerer assembly, before
you clamp the stem. If you just clamp the stem without
vertically preloading the assembly, you will end up with a
loose headset. Your options are to cut the tube, or add two
cm of spacer. The stem/spacers should be about 3mm above the
top of the steerer tube, so that when you screw down the top
cap it's pushing down on the stem/spacers and pulling the
steerer tube upwards, if you get the idea.

Rich