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What happened, Why and How much to fix?

LiebkuchenLiebkuchen Posts: 19
edited June 2013 in MTB workshop & tech
Finally been out on my second hand mtb- a 12 1/2" Bronx Equaliser , 24" wheels, 21 whole gears (I feel your envy!)

Just prior to my first ride on it, I'd messed up my front and back shifters trying to adjust them to the point I didn't know what I was meant to be doing any more. So I finally caved in and took it to my lbs to be adjusted properly. I thought it might need new cables too but apparently not so. Nice, cheap job. When testing it out before home, I noticed the rear gears were now back to front (ie 7 seems to be the lowest) but not a biggie. Also, that I seemed to have acquired sort of 'half gears' where the gears wouldn't engage fully so you have to shift up or down a couple of times to engage the chain-rings. Assuming the bike shop people know a lot more than I, I went home and I've been out on it a few times okay and coping with the quirks.

This was my fourth ride- the last one was 20 miles round our flat park loop which went well. I'd cleaned and lubed the chain last night, checked my gears etc etc. I had put a new chain on the bike before the shop trip.

This time I was heading out of town on a rural bike path which is much more up and down. Firstly, my bike was making that annoying ticking noise when I tried to ride in the largest chain ring - why?

Then I discovered (by falling off my bike and into the bushes twice trying to get up small hills) that the front gears are now also labelled back to front.

On my way back, the bike seemed more noisy. Then while trying to change up from the smallest sprocket the rear derailleur just wouldn't move. Stopped and inspected. Nothing obviously blocking movement so decided to carry on- could still pedal okay. After 5 mins it magically started working again...More noise on the way home until I was turning into a street with a steep incline and shifting down (or trying) when my chain basically jumped off the biggest chain-ring outwards, ripping the screws out of half my plastic bash ring and folding it in half where it now rests gloating at me next to my tool kit. [blub]

Why did this happen? How much is it going to cost to fix it? How often do your derailleurs need re-aligned? 3 short rides seems awfully soon. I'm trying to get the bike through to next spring before I buy a new one but while I'm enjoy the rides, I feel like a mortal enemy of this ****ing bike [add the profanity of your choice].

Posts

  • nicklousenicklouse Posts: 81,520 Lives Here
    so what have the shop changed?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • supersonicsupersonic Posts: 82,708 Lives Here
    Clean and refit cables or replace them
  • LiebkuchenLiebkuchen Posts: 19
    The shop set up my gears for me- adjusted the derailleurs so they would move the full range as normal as couldn't get them to shift properly regardless of how I tightened or loosened the high and low screws back and front. I did mention the cables might need replaced to the owner as the bike is a few years old so was happy when they hadn't touched them as it was cheaper for me. That's when I found these strange in between settings on my front chainset as I switched up or down- it no longer just went 1, 2 , 3 . It was now doing 3, not yet, not yet, 2, not yet, not yet, 1. Since the chain lept outwards, I can see the front derailleur is now moving too far out from the largest chainring- which it wasn't doing last night.

    I'm a complete noob armed only with my bike maintenance book and this forum so I kind of have to trust the bike shop knows best.


    Okay, so new plastic chain guard thingy and new gear cables- how much do you think it will cost?
  • cooldadcooldad Posts: 32,904
    I always replace inners and outers at the same time - about a fiver each end - but I buy Shimano SP41 outer in bulk and Shimano stainless inners 10 at a time.
    Forget books, read Parktools, link below or in Nick's sig above.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • The RookieThe Rookie Posts: 27,747
    If the LBS didn't change anything, then the gears must have always been like that...7th at the rear should be the smallest sprocket, 1 at the front always the smallest and impossible to make otherwise.
  • LiebkuchenLiebkuchen Posts: 19
    @cooldad- thanks for the link. I promise to bookmark it and read it. I'd been consulting Sheldon Brown's pages mostly but when it came to trying to put my chain back on properly I struggled to find a clear picture online I could follow hence the book.

    @The Beginner- I concede from what you say that the gears must have been back to front already. I have a terrible memory. I haven't ridden much and the last 2 rides I'd discovered a nice middle gear that worked well on gentle hills and the flat so I just suck with it until today when I needed more 'oomph'. Definitely gained extra shifts in the front chainrings between each 'bite'.

    Should a bike click or have a loud rhythm coming from the drive chain? I remember my old low tech bikes as a kid did. I honestly don't know if others do these days.
  • cooldadcooldad Posts: 32,904
    Nope sounds like the indexing is off.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
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