FSA Compressor installation

tightbarsteward
tightbarsteward Posts: 123
edited February 2014 in Workshop
Just received my new Moser 111 from Wiggle which Im really pleased with. However the 120mm stem on it is too long for my liking so I swapped it with a 100mm one off my old bike. However i just cannot seem to get the headset installation correct. Theres either a bit of play in the headset or it seems to over tighten & the bars dont turn freely. I just cant find the correct tightening torque. Is there a secret to installing an FSA Compressor Adjusterhttp://www.chainreactioncycles.com/fsa-compressor-adjuster/rp-prod2218? Ive installed quite a few headsets in the past including a Hope Head Doctor but Ive never had this type of problem before.

Any suggestion before I take it to my LBS gratefully appreciated

Comments

  • nicklouse
    nicklouse Posts: 50,675
    You have added more spacers to give you clearance between the top cap and the steerer.

    And that you are not pulling the compressor up the steerer?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • tightbarsteward
    tightbarsteward Posts: 123
    Oh yeah theres clearance between top cap & steerer but I just measured it & its 7mm. Too much?

    What do you mean by pulling the compressor up the steerer?
  • nicklouse
    nicklouse Posts: 50,675
    Well if you have 7mm then it is unlikely it is being pulled up the steerer unless the top cap has a 7mm insert depth. Which it does look like it has from the CRC image.

    I would say the bung is not in the steerer far enough
    And may also not be tight enough.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • tightbarsteward
    tightbarsteward Posts: 123
    Well ive swapped the stems back around on the bikes & the problem has gone! Works fine with the original FSA stem which came with the bike. Measuring them the FSA stem is 40mm high & the old Bontranger one is 45mm high. Before I swapped them back I tried a smaller 4mm spacer instead of one of the 10mm ones & that didnt work either. Still felt too tight.

    Puzzled. So if a bought a new 100mm stem which is 40mm high hopefully it will work
  • Salsa
    Salsa Posts: 753
    Those FSA bungs have the top cap built in and wind against the expander part, so it's possible to bottom it out before getting tight enough. Take it out and unwind the black top cap part as far as you can before it comes off then reinstall it, that will hopefully solve your problem.

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