Whats happening with my gears?!

[Dr Murdoch]

Ive just purchased a 2nd hand hard-tail and the rear derailleur setup is somewhat off! Initially I thought the chain was too small, and it still might be, but the derailleur is sitting at an odd angle.




The gears work fine, apart from getting into '1' as the cage hits the frame+cassatte, see pic.....



What's occurring and how do I fix it so that gear '1' can utilised?

[syko89]

Your mech has rotated against the frame I think. Can you loosen the main bolt holding it on and rotate back into position?
Hard to see but it looks like the tab on your mech to hold it against the frame may have snapped causing this. Unless the chains just way too short...

Also, the axle/skewer isn't sitting centrally in the dropout. Loosen this off and push it back into place so your wheel doesn't fall off

Edited by syko89 on Monday 9th June 15:11

[Dr Murdoch]

Brilliant thanks!

I think the tab has come off.

In which case, can I order any Deore 9 speed mech?

Couple more pics...



Not liking life on the top sprocket.....

[Freakuk]

I think the chain is too short, looking at the pics it's hard to say but you look to be on the big ring on the front and same on the back, so your rear mech shouldn't be as high as that and should have plenty of links in the chain to allow it to drop down. I suspect the chain it catching the mech when in the big cog on the rear as the chain is too short.

[G321]

The chain is way too short, no way the derailleur should be at that angle when on the big rings at the front and back

[Dr Murdoch]

Thanks all, i've ordered a new chain

[Harpoon]

Park have a good guide on sizing a new chain correctly:

https://www.parktool.com/en-int/blog/repair-help/c...

The special pliers to open/close the master link on a chain can be helpful, though if you are just closing it one way is to position the master link on the front chainring and then stamp hard on the pedals to hopefully close it.

[Dr Murdoch]

Thanks for all the responses, here is an update:

syko89 was eagle eyed and was correct in noticing the tab of the mech had snapped and therefore would not stay in position. SO I got a 2nd hand mech on ebay and simply took the bracket off and put it on the existing mech, all good.....

New chain on, started with 116 links, but reduced that down to 100, all good....

However, the chain comes off the front crank rather easily. The previous owner wanted a single crank, so simply removed the front mech (see pics below). The alignment works better when I use the bottom sprocket, but thats too small to maintain any useful speed on rides.





So what are my options?

1. Put a larger 'small' sprocket
2. Get a cheap front mech to crudely work as a chain stay.
3. Both of the above
4. Get a single speed crank, if so, how do i figure out the correct one? A quick look early suggest one was compatible with a square BB? Not heard of a square one!

[addey]

Get a 1x (narrow/wide) chainring, it has a different tooth profile to help retain the chain better. You might as well ditch both the current chainrings and fit a new 1x ring in whichever position gives you the best chain line. You don't need to change the actual crank arms, just make sure the new chainring has the correct BCD