Bicycle Mechanics - New to biking, need derailleur help

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JahRo225
08-16-11, 11:30 PM
I thought I'd mess around and see how the derailleur worked on my new bike, but I found out it's pretty cheap. I hardly even knew what a derailleur was until last week, now I see that my derailleur is cheap and it slightly angled. It's a Shimano TX35, should I maybe try and upgrade? How much would this cost? I tried looking online for help as to how to get the angle straight. Everyone says there's a high and low screw, but I don't even see those on mine to adjust. I messed with a few of the screws and saw no change whatsoever. I plan on bringing it back into my LBS tomorrow to see what they can do. Can anyone give me some advice or tips? Thanks :(


Mondoman
08-17-11, 01:11 AM
If you are not having any shifting or noise issues, just use the RD until it wears out or gets broken. Not sure what you mean by "angle"; if you could post photos, that would be a big help to us. The high and low limit screws just mechanically prevent the RD from moving out past the outermost rear gear and from moving in past the innermost read gear.

Check out this site for straightforward instructions:
http://www.parktool.com/blog/repair-help

Here's the RD procedure from the online Park Tool info:
http://www.parktool.com/blog/repair-help/rear-derailler-adjustments-derailleur

dabac
08-17-11, 01:22 AM
I thought I'd mess around and see how the derailleur worked on my new bike, but I found out it's pretty cheap... now I see that my derailleur is cheap ... It's a Shimano TX35..

While heavy and crude-looking, there's nothing inherently wrong with a TX35. Unless damaged or seriously worn, it should work just fine. Maybe not great, but you'd have a long way to go before you can blame the derailer for holding you back.


.. should I maybe try and upgrade?

As bike parts are much more expensive when bought piecemeal, upgradeitis can be a real costly affliction. Pretty much the only way to make make any kind of sense money-wise is to replace-with-nicer when a part is broken/worn out, but only then.

If you decide you want a new derailer for the fun of it, well that's another ballgame entirely.


.. How much would this cost?.. well, if you insist, anything from 30 USD to 250 USD for the part alone, depending on how much engineering overkill you'd want to apply.


..I see that my derailleur is..slightly angled.

I'm afraid this doesn't tell us much. If it sitting at an angle to the rest of the bike when viewed from behind, then it needs fixing or possibly replacing. Can be a bent hanger, can be a bent derailer.

It it's sitting at an angle when viewed from the side - well, it's supposed to do that. And the angle will depend on what gear you're in.

Pay heed to the old saying: "if it ain't broken, don't fix it".


. I tried looking online for help...

You can't have looked very hard then:
Park Tool on derailer adjustment (http://www.parktool.com/blog/repair-help/rear-derailler-adjustments-derailleur)
Park Tool on hanger alignment (http://www.parktool.com/blog/repair-help/rear-derailleur-hanger-alignment)
Sheldon Brown on derailers (http://sheldonbrown.com/derailer-adjustment.html#rear)


. my derailleur is .. slightly angled... Everyone says there's a high and low screw....

I think you're mixin g things up here. The high and low screws limit how far the derailer will move sideways, but aren't really used to adjust any "angle" I can think of.

There's a B-tension screw that can adjust the derailer front/rear angle and cage position a bit, if needed. It's usually not a particularly critical adjustment though.

Here: (http://techdocs.shimano.com/techdocs/index.jsp;jsessionid=K2HlTLhdGnXXnwFrW2qTL0s3M65BSQMYMCr1NTCdQq7mhBTfmZyF!1173381354) you can find the Shimano document for your derailer. Item 1 are the high/low screws. Unless you can't reach all the sprockets, or if the chain comes off the sprockets entirely, no need to touch these. And unless the derailer is resting against the correct one, you won't see any change as you turn the screws.
Item 4 is the B-tension (front/rear position) screw.


. I plan on bringing it back into my LBS tomorrow to see what they can do. Can anyone give me some advice or tips?

Read up on the links.

Plot your approach according to what you want. Are you just curious about how your bike works, or is it something in its performance that you're not happy with?
If the bike isn't behaving properly, are you sure it's the bike that's at fault, or is it maybe the rider who could do with some pointers on riding/shifting technique?


cyclist2000
08-17-11, 06:12 AM
here are the shimano tech docs that have the original instructions on setting it up.

tourney tech docs (http://techdocs.shimano.com/media/techdocs/content/cycle/SI/SI_5WU0A/SI-5WU0A-001-00-ENG_v1_m56577569830701975.PDF)

JahRo225
08-17-11, 03:59 PM
Good to hear feedback from guys that know what they're talkin about! Thanks fellas, took it in for a free tune up today before fall semester starts, the guy didn't find much wrong with it. Maybe I was just shifting it wrong, lol it's been a while since I've had a bike...

csnyder
08-18-11, 08:14 AM
When I was in college, I decided that I my bike (a decent full-suspension Giant MTB) needed to be upgraded. There were definitely issues - the chainrings and cassette were worn from a lack of chain maintenance - but I went about the upgrades in the wrong way. Rather than taking a slow, reasoned approach, with the advice of people here and at my LBS, I went out and purchased an entire set of Park tools, a new crank and chainring set, and a new cassette - all without bothering to check whether they'd be the right components for my bike. After dismantling the bike and fitting the new parts, nothing worked properly, and I was out hundreds of dollars. I ended up taking my younger brother's bike, which he no longer used, and building it up as a commuter. My Giant bike has been collecting dust for almost a decade now.

In short, you've made a good decision to wait - as you gain more experience and knowledge, you'll have a better idea of what you actually want. I also recommend reading as much as you can about your bike's mechanical components - these forums and Sheldon Brown's web site are great places to start.