Viewing 13 posts - 1 through 13 (of 13 total)
  • any advice for a bike numpty.going to fit a new stem/bars.
  • racefaceec90
    Full Member

    apologies for being stupid in advance.have always let the bike shop handle all fitting components to my bike e.t.c.they were quite busy though,when i picked up my ritchey alu flat bar (31.8) and 4 axis stem.do not have a torque wrench though.the bike shop suggested tightening the bolts tight enough/but not overtight.how tight do you do them? thanks in advance 🙂

    RustyMac
    Full Member

    Do you have an L shaped allen key? without a torque wrench it all comes down to feel.

    Best place to start is a bit of trial tighten trial tighten till everything does what it is supposed to. With Alu bars and stem there is a fair bit of tollerance for over tightening so i wouldn’t worry about going to far.

    Basic technique i use is

    1 – Always always start the bolts with your fingers – no tools, this will help prevent cross threading, you should alway be able to put the bolt in a good bit by hand. If you can’t get them in a few threads remove the bolt and insect everything is clean.

    2 – Holding the short end of the allen key tighten the bolts in a crossing pattern top left, bottom right, top right, bottom left untill all the bolts are tight.

    3 – Now change the allen keys to hold the long end of the allen key, this will provide more torque so you will be able to tighten the bolts more. Tighten in the same crossing pattern BUT ONLY 1/2 a turn at a time on each bolt. This is where the trial and tighten bit starts, if the bars still move then tightend the bolts by 1/2 a turn again.

    When you are happy they are tight go for a gentle cycle and see how they are with a bit of weight on them then ride down a kerb or something to test they still don’t move.

    By now you should have a reasonable idea of how tight the bolts need to be for future and you have tested it to check it will work in normal riding.

    racefaceec90
    Full Member

    Rusty Mac thanks for the advice. 😀 (have an allen key toolbox that i bought from focus.was pretty good value at £9.99 if i remember what i paid for it)will give it a go this weekend 🙂

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    RustyMac
    Full Member

    Just take your time, you can pretty much use that method on most bolts you need to tighten.

    GJP
    Free Member

    You can also buy a 4mm 5NM “key fob” style torque wrench for about £13 Ritchey do one which I have and it is really handy. Seen others available in my LBS recently as well

    Torque Key

    racefaceec90
    Full Member

    well have just finished fitting the bar/stem (woke up at 4:30 this morning) i thought to myself “well i still haven’t fitted them”.as they were looking at me with disdain (the components) i followed your advice Rusty Mac,and went slow and methodically fitting the items.i actually found the process relatively straightforward,well apart from messing up the order of fork lock out,shifter and brake lever. took a couple of shots of the new items now fitted (excuse the rubbish shots/general untidiness 😳 i must say that i really enjoyed doing the job myself.and would love to learn more about fitting/fixing things on my bike. am going to check that they are not loose,by riding to the bike shop later today.they said they would check them for me (torque,fitted correctly e.t.c 😉 right i’ll shut up now,but thanks again everyone for your help 😀 p.s the new bars are quite narrow compared to the risers (old skool baby 😉

    paul4stones
    Full Member

    I like the advice on Ragley packaging which says something like “if you need to ask you can’t do it”! You do realise that now you’ve started you’ll now spend most of your free time swapping components or scouring the classifieds for new bits rather than actually riding your bike. Enjoy 🙂

    RustyMac
    Full Member

    Hey racefaceec90,

    happy to help, looks like you have done a good job there! Good idea to get them checked if it is your first time, bike shop mechanics usually accept biscuits or jaffa cakes for these types of check up jobs 😉

    stumpy01
    Full Member

    Most difficult thing I find with getting a new bar & stem fitted is getting the pre-load of the headset correct, via the top cap bolt.
    I always have a nagging doubt that I’ve over-tightened it or not tightened it enough.
    Racefaceec90, you did tighten the top cap bolt before tightening the stem bolts, didn’t you?

    oliverd1981
    Free Member

    Having “the feel” for how tight an M5 bolt should be is an essential skill all cyclists should have. It could destroy many a LBS if that idea ever caught on though.

    racefaceec90
    Full Member

    stumpy01 yes i did.i must confess though that i did it wrong.when i went to the bike shop,they had to put a washer below the top cap so that it would have something to tighten against (i had taken a spacer off,thinking it was too high).other than that though,i seemed fit them ok. p.s am clueless about the top cap/star fangled washer ❓ (i think it tightens the forks to the headset,stops it coming loose?)

    PJay
    Free Member

    I’m getting used to fitting stems now after being very nervous early on about getting the pre-load right. I think that I tend to over-do, rather than under-do, the pre-load but I’ve yet to wear out any bearings. The advice I’ve been given is that if bars spin freely and there’s no detectable play at the races or juddering when you ride, then it’s good enough.

    stumpy01
    Full Member

    racefaceec90 – Member
    stumpy01 yes i did.i must confess though that i did it wrong.when i went to the bike shop,they had to put a washer below the top cap so that it would have something to tighten against (i had taken a spacer off,thinking it was too high).other than that though,i seemed fit them ok. p.s am clueless about the top cap/star fangled washer (i think it tightens the forks to the headset,stops it coming loose?)

    Yeah – sounds like you did the top cap up directly against the steerer, rather than against the top of the stem (if your steerer tube doesn’t poke out the top) or a spacer (it if does poke out the top).

    The star fangled washer is just an insert that enables you to tighten the top cap into the steerer tube.
    All the top cap & screw does is pull the fork up into the bike frame (and headset) and keep the whole assembly tight.
    If you had no top cap at all, then the only thing keeping the fork in the frame would be the stem and the fact you have tightened it onto the steerer.
    When you tighten the top cap, the screw pulls the fork up into the frame. As it tightens up, it takes up the slack in the assembly, seating the bearings in the headset correctly and keeping it all together. The top cap needs to rest against either the top of the stem (with no interference with the steerer tube underneath)or a spacer placed on top of the stem, as it needs something to pull against. If it doesn’t sit on the stem or spacer, then the only thing it can rest against is the top of the steerer tube and if it’s doing that, then there is nothing for it to ‘pull’ against to tighten the whole lot up. All you would be doing is tightening the top cap into the steerer tube, not pulling the whole lot together.

    EDIT – if you don’t tighten the top cap enough, then the bearings don’t sit correctly and have some play in them. This will knacker them quickly, and allow grit to easily enter the assembly.
    If you tighten the top cap too much, then you squash the bearings together too much, which will make the steering stiff & cause the bearings to fail prematurely, as they are being crushed.
    As above, the top cap should be tightened up so the handlebars still rotate easily, but there is no play between the fork and the frame. I check this by holding the headtube of the fram and the crown of the fork and pulling them backwards and forwards. There should be no movement or knocking.

Viewing 13 posts - 1 through 13 (of 13 total)

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