Safety of removing a steerer expansion bolt from a carbon steerer purely to save weight.

Once you've tightened your headset and stem, the expansion bolt
assembly that drops into the carbon steerer tube no longer appears to
serve any purpose. It weighs 2-3 ounces. If I save that weight by
removing the bolt assembly, is this safe?
It was suggested to me that the expansion assembly stops the stem from
over-compressing the steerer tube, and that it adds strength to the
whole system. Is this correct, or indeed is there good reason not to
pull out the bolt and replace it with a packed bar-end-plug so as to
save weight on my hill-racing bike.
Any comments would be welcomed.

BigFella wrote:
Once you've tightened your headset and stem, the expansion bolt
assembly that drops into the carbon steerer tube no longer appears to
serve any purpose. It weighs 2-3 ounces. If I save that weight by
removing the bolt assembly, is this safe?
It was suggested to me that the expansion assembly stops the stem from
over-compressing the steerer tube, and that it adds strength to the
whole system. Is this correct, or indeed is there good reason not to
pull out the bolt and replace it with a packed bar-end-plug so as to
save weight on my hill-racing bike.
Any comments would be welcomed.


Why bother? In other words, what are you trying to accomplish?
Do you really, really think it'll make you faster?


Robin Hubert

Why bother? In other words, what are you trying to accomplish?
Do you really, really think it'll make you faster?

The title states what you're trying to accomplish. It won't buy you
much, but then neither will any single change you make to make a bike
lighter. They all add up. People seem to spend about $400+ per pound of
weight saved. The lighter your bike gets, the greater than expense.
This change would thus be worth about $60+, and is free, plus takes a
minute, so if you have some v v hilly races then the question is worth
asking.

BigFella wrote:

: It was suggested to me that the expansion assembly stops the stem from
: over-compressing the steerer tube, and that it adds strength to the
: whole system. Is this correct

Yes.

This is also why you have to be careful to ensure that the expansion
assembly is not below or above the stem.

Arthur

--
Arthur Clune PGP/GPG Key: http://www.clune.org/pubkey.txt
The struggle of people against power is the struggle
of memory against forgetting - Milan Kundera

BigFella wrote:
Once you've tightened your headset and stem, the expansion bolt
assembly that drops into the carbon steerer tube no longer appears to
serve any purpose.
Any comments would be welcomed.

I once made this same assumption and found it to be erroneous. An issue
I discovered inadvertently is how easily a stem on a carbon steerer
tube can work its way loose, perhaps because of the slipperiness of the
carbon surface or possibly from the lack of internal support for the
steerer tube (this was on a Reynolds Ouzo fork). Once the proprietary
Reynolds anchor plug was reinstalled, everything stayed securely in
place.
Obviously this may differ with different forks and stems.

DR