Holowtech II questions

Marjory Stewart BAxtor
edited April 2008 in MTB workshop & tech
Firstly, are there meant to be cap discs or crank bolts or something on the sides as it all seems very very see through. I understand that's why it's `hollow`tech, just wondering if it needs a dust seal.

secondly, what's this plastic hoofer in the non=drive side? I have it screwed in and I have the tool to adjust it but what's it do/for?

Lastly, I have a 68mm shell and I don't use a BB mounted mech so I thought I was supposed to put two 2.5 spacers on the drive side and one on the non-drive side (as I read on park tools), however my xt mech wont stretch to the outer chainring, so i took out both spacers from the drive side (so the bearing cup is flush to the shell) and it the mech was the right distance but it meant I now have two spacers on the non-drive side to make the axle the right length for the other crank.

have I done anything wrong in my installation??
ta ben
Train hard, ride easy

Comments

  • nicklouse
    nicklouse Posts: 50,673
    have you actually read the instructions?

    no dust seals.

    preload the bearings.

    and yes the spacers sound right. maybe you need to re set the mech? or what chainline should the frame have. measure the old and set the new to suit.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • nicklouse wrote:
    preload the bearings.
    how does this work?? I can't get my head round it. How can I tell how exactly to adjust this mysterious plastic thingmyjob?
    nicklouse wrote:
    maybe you need to re set the mech? or what chainline should the frame have. measure the old and set the new to suit.
    how do I re-set the mech? and what's a chainline?

    excuse the dunseness, this is all extra to park tools guide I read
    Train hard, ride easy
  • supersonic
    supersonic Posts: 82,708
    The preload and bearing adjust is in parktools. You need a special tool for it. Imagine the system like a headset - the axle is the fork steerer, the LH crank the stem. Adjust the preload and then the crank arm ('stem') bolts to keep it in place.

    Chainline is explained very well in Sheldon Brown's site with diagrams. Moave the chainset out, then it follows you must adjust the front mech. Again, Park Tools for this!
  • nicklouse
    nicklouse Posts: 50,673
    have you actually read the instructions?

    :roll: so the answer is no.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • i see, i have the tool to adjust the thingy job so I'll read the preload article.

    the thing about chainline is taht when I Pull the mech out til it won't go any further and it still isn't in the right position on the outer chainring
    Train hard, ride easy
  • had a play with them and so far as I can tell they are as lazx as they'll be going
    Train hard, ride easy
  • supersonic
    supersonic Posts: 82,708
    You need to set the mech from scrath - the lower stop and the higher. The mech cannot reach the H stop if there is not enough tension in the cable.
  • sounds like a big pain. I still don't know how to set my mechs. for the back i just adjust the cable and live with the fact that it doesn't shift into the smallest back cog
    Train hard, ride easy
  • supersonic
    supersonic Posts: 82,708
    I don't think I could write a guide any simpler than Park! Try setting the limit stops without the cable attatched. Then re attatch, and use the barrel adjusters.
  • lol, I know full well HOW to and WHAT to do with the mechs it's jsut the adjusters on my xt front and lx rear don't seem to do anything
    Train hard, ride easy
  • supersonic
    supersonic Posts: 82,708
    When the cables are out, set the adjusters back to the middel (they are just screws!)

    Clean the cables too.
  • does `middel` mean half pertruding out?
    Train hard, ride easy
  • supersonic
    supersonic Posts: 82,708
    Aye. Half the threads in. Well actually two thrids in is better.
  • i see. I'll have a tinker around somewhat
    Train hard, ride easy
  • ian_worby
    ian_worby Posts: 331
    [quote="
    Lastly, I have a 68mm shell and I don't use a BB mounted mech so I thought I was supposed to put two 2.5 spacers on the drive side and one on the non-drive side (as I read on park tools), however my xt mech wont stretch to the outer chainring, so i took out both spacers from the drive side (so the bearing cup is flush to the shell) and it the mech was the right distance but it meant I now have two spacers on the non-drive side to make the axle the right length for the other crank.
    [/quote]

    As far i know, you require three spacers in order to set everything up now, so if you're drive cup is flush with the fram eyou shoudl have 3 spacers on non drive side, which isn't good, as you have very little tread in th frame

    really it sounds like you'll be best with 1 on drive side and two on non-drive
  • Anonymous
    Anonymous Posts: 79,666
    Seriously though...
    Take it to your local bike shop. :roll:
  • skyliner
    skyliner Posts: 613
    Well said Ian.
    Or take it to a bike shop that have good mechanics, and let them do it for you.
    If you've not had the BB shell faced & chased, they'll be able to do this before fitting the BB correctly. And save you a whole lot of trouble in future for less than £15 in most cases.
    It's nice to be important, but it's more important to be nice.
  • ian_worby
    ian_worby Posts: 331
    shame my typing is so appalling
  • thamacdaddy
    thamacdaddy Posts: 590
    To be fair to the OP I can understand that the advice you guys are giving on his front mech although sound might not work. I have just installed a new XT front mech and it has a much smaller range of movement than the old LX one I had. I hadn't though about it but want to install hollowtech myself in the next six months and need to measure that the current distance the crankset is from the BB shell will be the same or less with hollowtech otherwise I will have the same problem with the Front mech (its not about the limits or the cable tension but the degree of motion in the swingarm of the mech).

    Might help if you check which XT mech you have as well.

    Mine was this one:

    http://www.chainreactioncycles.com/Mode ... delID=3407


    and I imagine with the extra distance the outer bearings will have on hollowtech I might have to change it if I move from my firex with a square taper BB.
  • ian_worby
    ian_worby Posts: 331
    admittedly the external bearing setups do cause mechs to sometimes go to they're limit of reach, especially if you follow the offical advice of two spacers on the drive side.

    however with just one on the drive side it should work fine, the only reason i've ever had problems is when i mech has worn bushes an too much play to enable it to shift properly.

    the q-factor is larger on the hollowtech twos (and all external setups) compared to old fashioned square taper but you have to rememeber that when fitted, the granny ring & middle ring sit over the bearings and into a 'simliar' postion to what they would've been
  • supersonic
    supersonic Posts: 82,708
    To be fair to the OP I can understand that the advice you guys are giving on his front mech although sound might not work. I have just installed a new XT front mech and it has a much smaller range of movement than the old LX one I had. I hadn't though about it but want to install hollowtech myself in the next six months and need to measure that the current distance the crankset is from the BB shell will be the same or less with hollowtech otherwise I will have the same problem with the Front mech (its not about the limits or the cable tension but the degree of motion in the swingarm of the mech).

    Might help if you check which XT mech you have as well.

    Mine was this one:

    http://www.chainreactioncycles.com/Mode ... delID=3407


    and I imagine with the extra distance the outer bearings will have on hollowtech I might have to change it if I move from my firex with a square taper BB.

    You sometimes do get a problem with mechs bottoming out on the frame, and not its stops, when the chainline is small at the front. Can occur when the seat tube is oversized, hence the frame manufacturer recomends a larger chainline, ie 50mm. I've never seen it the other way, and I have 2 XT front mechs, inc the one you have and no probs at all with full range.