Bicycle Mechanics - carbon steerer

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View Full Version : carbon steerer


dexmax
07-12-03, 05:49 AM
I know I am not supposed to use a "spangle" on forks w/ a carbon steerer..

But, i'm hard-headed, I still did...

It won't do... SO i removed that star-like blade-like nut...

What we(me and a friend) did is this(please see pic below):

We placed in a long stud and on the bottom screwed in a nut(the one that touches the bearings on a hub) placed an extra spacer on top of the stem then placed a wide washer on top of the spacer..

Then we screwed a hex nut on top then tightened it...

After achieving the "correct" fit, I tightened the stem unto the steerer..


My question is, is this what you guys do with carbon forks with carbon steerers?


RacerX
07-12-03, 06:13 AM
jeez dude, that looks scary.
Did you do that with a carbon steerer?

Anyway, the purpose of a carbon steerer is light weight and maybe some shock absorbtion. You effectively canceled any weight savings with what you did there and it looks scary because that type of clamping is untested. You really don't know what kind of stresses that is putting on your fork.

Normally, you use a compression nut on carbon steerers. Some, like Cannondale, still use a star nut but you should do whatever the specific manufacturer suggests. Anything else can be very dangerous.

KevinG
07-12-03, 10:50 AM
Some BMX, DH, DS and MTX riders use a system simaliar to that by Azonic called the Headlock.
I would not trust it on a Carbon Steerer Tube. Their is reason that most Makers of full Carbon forks insist you use a compression plug.
Personal I would not ride that fork after installing and removing a star nut. You have scored the interior of the Steerer and there is a very good chance that it will fail alnong those score lines.


Dave Stohler
07-12-03, 01:14 PM
I certainly wouldn't do that.

bfong
07-12-03, 02:12 PM
They make carbon steerer specific systems.

http://www.supergo.com/itemdisplay.asp?parentid=18112&secid=24&subid=1514

F1_Fan
07-12-03, 02:15 PM
Originally posted by RacerX
You effectively canceled any weight savings with what you did there and it looks scary because that type of clamping is untested. You really don't know what kind of stresses that is putting on your fork.

I *think* he just used it to preload the bearings. Once the stem is tightened onto the steerer that assembly can be removed.

As with a normal setup once the stem is tight the top cap and star nut are just along for the ride.

roadfix
07-12-03, 02:47 PM
Originally posted by F1_Fan
I *think* he just used it to preload the bearings. Once the stem is tightened onto the steerer that assembly can be removed.

As with a normal setup once the stem is tight the top cap and star nut are just along for the ride.

Ditto........I concur with your reasoning 110%

dexmax
07-13-03, 11:52 PM
Originally posted by F1_Fan
I *think* he just used it to preload the bearings. Once the stem is tightened onto the steerer that assembly can be removed.

As with a normal setup once the stem is tight the top cap and star nut are just along for the ride.

Thanks for explaining what I was doing.. wasn't able to log in for a while...

That plug specific for carbon steerers.. I can't find that locally, so I had to resort to other methods just to prestress my bearings...

Actually, i don't need to put a star-flanged nut anymore.. I only need to cover the hole.:D