stem/bar compatibility

[pg]

After my Ritchey WCS stem cracked near the lower bolt on steerer tube
end (on downhill, but didnt fall), I replaced with the only stem local
shop had: FSA 150 OS. Handlebars are Ritchey WCS 31.8. New and old
stem indicate 31.8 diameter as well, but I noticed that, with new FAS,
handlebar clamp has about 2 mm gap between faceplate and stem body, on
both top and bottom . Also, Ti bolts coming from faceplate seem to be
seated about half way into the ful length of the threads on stem body.
I can get several full turns of bolts. but Im used to seeing bolts
extend beyond the end of the threads on back side.

On old setup the faceplate pretty much made contact with stem on top on
bottom. Is the new setup normal variation in gap between faceplate
body of stem, or could this be a compatibility issue?
thanks
Peter

 

[Nate Knutson]

pg wrote:
> After my Ritchey WCS stem cracked near the lower bolt on steerer tube
> end (on downhill, but didnt fall), I replaced with the only stem local
> shop had: FSA 150 OS. Handlebars are Ritchey WCS 31.8. New and old
> stem indicate 31.8 diameter as well, but I noticed that, with new FAS,
> handlebar clamp has about 2 mm gap between faceplate and stem body, on
> both top and bottom . Also, Ti bolts coming from faceplate seem to be
> seated about half way into the ful length of the threads on stem body.
> I can get several full turns of bolts. but Im used to seeing bolts
> extend beyond the end of the threads on back side.
>
> On old setup the faceplate pretty much made contact with stem on top on
> bottom. Is the new setup normal variation in gap between faceplate
> body of stem, or could this be a compatibility issue?
> thanks
> Peter

The gap between stem and faceplate varies from stem to stem. Some
makers try and minimize it as much as possible, perhaps because they've
got a theory that it might make a difference to get them super close.
Note that it's important for the bolts to be engaged evenly so that
they're not both at an angle when secured. Usually this is done by
making sure the gap on both the top and bottom are equal as you tighten
them back and fourth until they're all not moving when under final
torque.

It's also pretty normal for handlebar mounting threads to be deep or go
all the way through the stem, but if by "I can get several turns of the
bolts" you mean there's literally only several complete threads engaged
on the bolts then something is wrong.