Rear Derailleur Woes

DirkVoodoo

Evening all!

Well, I've been fiddling around with my bike for the last few days and haven't seen a geared bike setup correctly in a while. I've finally got everything back together, but I have forgotten what my bike used to look like.

Basically, when I shift onto the largest front chainring and largest rear sprocket (50-25, don't worry, I'm only looking at the derailleur movement and know not to ride this gear!) I can't remember what the correct derailleur angle is. I'm convinced that I have managed to fudge something up.

I flicked through images of beauty to find someone with a badly adjusted resting gear, but no joy! Google images is also no help.

Would one of you guys mind posting a photo of your bike in a similar gear, just to put my mind at ease?

Cheers!

DirkVoodoo

This is what it looks like (might have to tilt your head slightly):

The tax man

Just stuck my bike into a 50-27 setup and it looks similar to your picture.
Hanger is pulled forward at a nasty looking angle.

That is what you meant isn't it?

DirkVoodoo

The tax man wrote: »

Just stuck my bike into a 50-27 setup and it looks similar to your picture.
Hanger is pulled forward at a nasty looking angle.

That is what you meant isn't it?

Phew! Yes, thank you Tax Man. Just one of those things where a second opinion makes all the difference.

Planet X

Enter Mr. Skeffington?

kenmc

Looks totally fine.

Caroline_ie

your doggie looks bored,... behind the bike Dirk

kenmc

Caroline_ie wrote: »

your doggie looks bored,... behind the bike Dirk

s'ok, I'll call around later and give it a kick.

Oh and there's aliens living in your handlebars.

peterako

Looks fine

Every aspiring bike mechanic should have Sheldon Brown's (RIP) pages bookmarked.

Here's the derailleur page for you!

http://sheldonbrown.com/derailer-adjustment.html#chain

I seem to remember him having a picture of extreme gear selections showing the rear derailleur at angles like in the picture above in this thread. And all were commented as OK. And coming from Sheldon this is as near to an infallible statement as you're likely to get in the bike world!

Best of luck,
Peter

seamus

You really only need a slight bend in the "elbow" of the mech at these extremes. The idea being that for every gear combination, the chain should be fully resting/pressing on the jockey wheels, and the spring in the elbow of the mech should be maintaining tension in the chain.

If the chain is too short and the mech is almost dead straight at these extremes, then the chain doesn't properly connect with the jockey wheels and the mech is exerting little or no tension on the chain (in fact, it's the chain exerting tension on the mech).