# How much to tighten your star nut?!



## yellowwducky (Jan 1, 2004)

Hi there,

So I looking at how the stem attaches to the steering tube and star nut - it seems to me the stem clamp bolts (if screwed tightly) go a long way to stop you from just pulling off your bars and stem if you try and pop a wheelie. The top bolt through the star nut in the steering tube also seems to do it (works with the stem clamp bolts).

So, when putting on bars, I gather I tigthen down the stem clamp bolts quite tight so the steering stays straight (and also helps hold everything on). But how tight should one tighten through the star nut? It seems if you were to get to aggreive, you would just pull the star nut out (and this can't be a good thing?!).

Regards,

yd


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## mtber36 (Mar 12, 2004)

*Tighten the top cap*

aka star nut until it is tight enough that there is no play in the headset. You can detect play by holding your front brake and rocking the bike back and forth with the other hand on the headset. Once you achieve that, check how the front end moves when you turn the handlebars. It should move freely. There is no need to crank on the top cap. Once the top cap is tightened correctly, tighten the stem bolts. They should be as tight as you can get them by hand.


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## yellowwducky (Jan 1, 2004)

cool! thanks for that mtber36


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## Schtoojp (Mar 20, 2004)

The top cap bolt is to set pre-load for the headset bearings. Adjust the preload till the bearing is tight, but the steering still moves freely with no play/movement. Then lock up the stem bolts and back off the topcap bolt. The stem bolts should hold the adjustment, and releasing the tension of the topcap saves it trying to keep on applying tension against something that is not going to move anyway. Make just lightly nip up the topcap bolt so it wont come loose and fall off. 

After it's initial job, it's a dustcap.


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## fred3 (Jan 12, 2004)

You tighten the top cap bolt prior to tightening the stem bolts. Like Schtoojp said the top cap is a pre-load for the bearings. Not too tight, Not too lose. Too tight and the bearings will grind and wear out quickly. Too loose and the steering will be floppy and a lot of things will wear out quickly. Just snug it up. The tighten the stem bolts, but not enough to deform the steerer tube.

The top cap will not hold on the stem/handlebars.


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