New Stem ,Steerer Tube now slightly long.

[MacB]

The top-cap and its bolt can indeed safely be removed once the stem's steerer bolts have been correctly tightened but there is no earthly reason for loosening it off half a turn. I'd certainly be interested to hear the 'reasoning' behind such a notion. For a laugh.

Without having the bike mechanic here to quiz on the subject I would assume it's to do with relieving a stress point. It could be nonsense but, as you agree it can't do any harm, then why not? I will, of course, attempt to find out the reasoning behind it

 

[Steve Austin]

The top-cap and its bolt can indeed safely be removed once the stem's steerer bolts have been correctly tightened but there is no earthly reason for loosening it off half a turn. I'd certainly be interested to hear the 'reasoning' behind such a notion. For a laugh.

I think its form folk tightening until its tight and then undoing a smidge to prevent crushing bearings?

'i'm shuddering at the thought but its an idea why'

 

[Steve Austin]

Thinking about it: when we all had threaded headsets it was common to tighten the bottom nut until it was a bit tight, then loosen that one of onto the top nut. Maybe its a residue from there

 

[Banjo]

My cap screw is too short with the spacer back in so I have refitted the old stem for now.Would a longer screw be the answer or a thinner spacer?Would most bike shops stock one or both of the above?

 

[Alien8]

My cap screw is too short with the spacer back in so I have refitted the old stem for now.Would a longer screw be the answer or a thinner spacer?Would most bike shops stock one or both of the above?

It all sounds a bit marginal.

Like lukesdad said, when you start to compress it together you want to be sure that the bolt is properly engaged in to the nut.

It depends how much you'll be reducing the stack height by with a thinner spacer, ie will the bolt be properly in the nut when you start to tighten it.

A longer bolt, if you can get one, would probably be the easiest route to take.

 

[Banjo]

Many thanks for all the replies,All fixed with a 2 mm carbon spacer from LBS .The bolt now has exactly the same distance to reach as before so all is good. I am learning that even the smallest job on a bike can have more pitfalls than you would think.

 

[youngoldbloke]

- yes, until you change one you assume that all stems have the same stack height - and that is certainly not the case, and it is not until you do it that you appreciate the need for a supply of spare spacers - I also used the opportunity to bling it up a bit with some new carbon-fibre ones!