Front Mech issues

dansims372
dansims372 Posts: 25
edited August 2009 in MTB workshop & tech
I have just come back from Afan Forest and my front mech is rubbing on the chain even more than ever.

What is the best method to stop this rubbing, do i need to adjust one of the two screws on the mech to stop this rubbing?

Comments

  • Andy B
    Andy B Posts: 8,115
    The 2 limit screws should be set up & left alone

    Probably cable tension, adjust by turning the adjuster on the shifter until you get the desired effect.
    2385861000_d125abe796_m.jpg
  • nicklouse
    nicklouse Posts: 50,673
    where is it rubbing on the mech? and in what gears. (most likely tension as Andy says).

    Rear the set up info on parktools.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Its rubbing in the low gears, i have to push the front mech leaver to push mech over to stop rubbing which is not that great.

    I will give the adjustmen a go and let you know.

    Have you guys been to Afan?
  • rhyko7
    rhyko7 Posts: 781
    turn the bike upside down, see what gears its rubbing in, it could be cable tension or you may have knocked it and just needs repositioning, if you take a pic of it upside down with it rubbing & post we can tell ya exactly what to do.
    Dont look at it-ride it! they are tools not f*cking ornaments

    my riding:
    http://www.youtube.com/user/rhyspect

    Some of my Rides Data/maps:
    http://www.trimbleoutdoors.com/Users/527337
  • I have some pics, how do you atatch them to this message?[/img]
  • nicklouse
    nicklouse Posts: 50,673
    read the how to in the BR FAQs.

    you need to host them somewhere first.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • How about these, not the best but not a easy thing to take pics of.

    sdc10435x.th.jpg
    sdc10434r.th.jpg
    sdc10433s.th.jpg
    sdc10431t.th.jpg
    sdc10431n.th.jpg
  • supersonic
    supersonic Posts: 82,708
    There is no need to run that gear - small front chainring and small rear cogs. The chain is angled, can cause rub, and wears things down much quicker.

    Yoo can get the same ratio in the middle chainring and a larger rear sprocket.

    Your derailer still may need a tweak though.
  • I was going up and down hills so i was in small cog, i normally use middle ring but for mountain biking off road i need lower gears, legs tire other wise.

    Ill try playing with rear mech.

    Thanks for ur help.
  • supersonic
    supersonic Posts: 82,708
    Change front gears to suit - if going to hit a downhill, move into the middle or larger ring, not the small ring with small rear cogs.
  • nicklouse
    nicklouse Posts: 50,673
    no. you should never use both small cogs you gain nothing. but gain more chain wear and more chance of breaking your chain.

    22-11 is the sameish as using the middle ring and 5/6/7 on the cassette (depends on what cassette you have fitted. 32-16.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • rhyko7
    rhyko7 Posts: 781
    supersonic wrote:
    Change front gears to suit - if going to hit a downhill, move into the middle or larger ring, not the small ring with small rear cogs.
    i agree with this

    ive looked at your pics, the mech doesnt look out of position, you just need a bit more cable tension-cables do stretch after a while., you can either turn the adjuster out on the gear lever (assuming there is one) or just pull a few mm of cable through the cable clamp on the mech, to do this put it on the smallest cog grab the cable with pliers, losen the 5mm hex clamp and pull the cable through (only a little bit) then re-tighten it. you will soon get a feel for it and know how much cable tension you need if you play around with it for a while.

    i tend not to run on the small cog up fron unless im goin up a steep hill, dont use the small one for DH because you will have no chain tension and it will bounce off
    Dont look at it-ride it! they are tools not f*cking ornaments

    my riding:
    http://www.youtube.com/user/rhyspect

    Some of my Rides Data/maps:
    http://www.trimbleoutdoors.com/Users/527337