Forum home Mountain biking forum MTB workshop & tech

Re-fitting deraileurs et al.

pygmyarrpygmyarr Posts: 3
edited October 2011 in MTB workshop & tech
hi folks, new to this proper bike malarkey after i made a mistake on how hard to press one of the pedals in the car.... :oops:

i've bought a bike from gumtree locally, but the previous owner has fettled with it quite a bit getting him right for himself, at the moment it is single gears front and back and a very very soft rear air suspension shock, but i'd like to return it to somewhere near stock to make my commute to work/bash about the new forest a bit nicer for me.

which would be the better way to get it sorted... fit all the parts as best as i can and get my local shop to tweak and finish off in a service.. or just hand them the bag of bits and puppy dog eyes them for a decent price...? my mechanical skills aren't great, although bolt on bits should be ok for me, i think i'd struggle with stuff like gear cogs, setting up the deraileurs correctly, fitting the chain on... unless you guys can reassure me they're pretty straight forward jobs..

and before i try, can i put more air into the shock with a standard bike pump..?

about the bike, all i can gather from looking about google images, is that it is Giant by brand, and probably NRS by model (some pics have the same rear end, others have slightly different, guessing manufacture year is the difference)..
http://i699.photobucket.com/albums/vv35 ... /bike1.jpg is a picture of it..

Posts

  • 1mancity21mancity2 Posts: 2,355
    To get it to run gears will cost, chainrings, cassette, mechs, shifters, I would leave it single speed but change the gearing to one you can happily pedal around.

    The rear shock needs a shock pump to get air in.

    Count how many teeth you have on the front "cog" and the rear "cog" and let us know the numbers.
    Finished, Check out my custom Giant Reign 2010
    Dirt Jumper Dmr Sidekick2
  • You can't use a normal pump that is high volume / low pressure to put air into a shock, you need a specific shock pump that is low volume / high pressure.

    Have a look at the Park Tool website, their guide to bike repairs is excellent.

    Park Tool repair and servicing guide
  • The RookieThe Rookie Posts: 27,756
    Depending on how the conversion has been done, you may need a new rear wheel.

    I would suggest going 'one by' that is not having any gears at the front , that will save you a lot of hassle and cost.

    For the rear you'll need a cassette, shifter (same number of gears), a rear mech and possibly a chain (most single speed chains are 7/8 speed so if you go 7/8 you won't need a chain) and the cable. You'll also need a new rear wheel if the current one is single speed specific (a photo of the drive gear will tell us) and a chain guide for the front (superstar is best/cheapest).

    Simon
  • First up, when i bought the bike, the chap gave me all the bits he'd taken off, so i have the 2 shifters, the 2 deraileurs, and the 2 sets of cogs.. maybe i could have made it clearer in the first place...

    as it stands right now, i have everything fitted bar the small front cog (cant get the pedal arm of fthe crank atm) and the back wheel cogs (probably need some sort of special tool to undo the single cog)

    everything else is fitted, and i have booked the bike in at halfords cycle repair centre here in bournemouth for a gear service, and 15mins time for pumping the shock up...

    if i get time later on tonight i'll stick a couple of pictures up on my photobucket...

    thanks for the advice.
  • nicklousenicklouse Posts: 50,675 Lives Here
    you need a crank puller and a cassette tool and a chain whip.

    see parktools for how tos.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • cooldadcooldad Posts: 32,599
    You also need a shock pump.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
Sign In or Register to comment.