Stem to steerer height difference question

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Glyno
Posts: 3
Joined: 11 Aug 2018, 8:52pm

Stem to steerer height difference question

Postby Glyno » 11 Aug 2018, 9:09pm

Hi, new member here, I do hope this isn't a daft question or one that's been asked a million times, so please go easy on me!

I'm in the process of swapping the stem on my bike. However, with the new stem in position there is barely a mm from the top surface of the stem to the top of the steerer (in fact, they're practically flush) and I'm unable to fully eliminate the headset 'play'. The question is - would I be able to add a 5mm spacer below (or even above) the stem to give me enough to gently tighten down the headset cap, or would it be too much of a difference between the top of the stem and top of the steerer?

...I suppose I could try and get hold of a 3mm spacer, but that would mean not going out tomorrow :(

I hope that makes sense and I haven't made that all seem complicated.

Thanks in advance,
Glyn.

Brucey
Posts: 29939
Joined: 4 Jan 2012, 6:25pm

Re: Stem to steerer height difference question

Postby Brucey » 11 Aug 2018, 9:17pm

most stems will work OK with ~2-3mm extra spacer, ~6mm extra spacer is too much; it might be OK for a short while, but I would be cautious of using it this way if the steerer is carbon though.

If you have a 3mm spacer under your stem at present, just swap it for a 5mm one, if a 5mm one is all you have.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Glyno
Posts: 3
Joined: 11 Aug 2018, 8:52pm

Re: Stem to steerer height difference question

Postby Glyno » 11 Aug 2018, 9:22pm

Thanks for the reply Brucey,
All I have to hand at the moment are a combination of 5mm and 10mm spacers, hence requiring a 3mm spacer would mean no riding tomorrow. I might risk the height difference of 5mm for the time being. It's not carbon btw.

gregoryoftours
Posts: 751
Joined: 22 May 2011, 7:14pm

Re: Stem to steerer height difference question

Postby gregoryoftours » 13 Aug 2018, 12:05am

If you add the 5mm spacer above the stem you don't have to worry about the stem not clamping enough of the steerer. The spacer doesn't have to locate on the top of the steerer if the steerer ends just below the top of the stem, it's only providing the top cap with enough height to enable it to pre load the bearings.

peetee
Posts: 530
Joined: 4 May 2010, 10:20pm

Re: Stem to steerer height difference question

Postby peetee » 13 Aug 2018, 12:39am

Deleted duplicate post
Last edited by peetee on 13 Aug 2018, 12:46am, edited 1 time in total.
Current status report:
Latter side of fifty and feeling less than nifty.
Too many bikes on pegs and too few miles in the legs.

peetee
Posts: 530
Joined: 4 May 2010, 10:20pm

Re: Stem to steerer height difference question

Postby peetee » 13 Aug 2018, 12:43am

As Brucey says, add the spacer above the stem. That way your bar height is not affected. The top bolt can be replaced with a longer one if necessary and by design it should not turned down tight like the old quill stems were. It's purpose as it is slowly wound in is to hold the stem and spacers together which, if they collectively remain a few mm above the steerer tube, will take out the slack in the bearings. Once the adjustment is right the stem bolts are tightened and all should be well.
Current status report:
Latter side of fifty and feeling less than nifty.
Too many bikes on pegs and too few miles in the legs.

Glyno
Posts: 3
Joined: 11 Aug 2018, 8:52pm

Re: Stem to steerer height difference question

Postby Glyno » 13 Aug 2018, 7:02pm

Thanks again for the helpful advise,

Glyn