Rear bike derailleur

[Cyclelover1997]

Hi everyone, brand new to cyclechat.net. I am just wondering how I put the rear derailleur back on to frame had to remove as had to fix puncture on tyre....

Cyclelover1997

 

[Rickshaw Phil]

Hi and to the site.

That looks like a basic clamp on derailleur similar to what I've got on the knockabout bike. You should have a bolt and a shaped nut that do the clamping and it should fit together like in these photos:

I hope that's of some use. For next time; once it's all fitted correctly the derailleur doesn't actually have to come off in order to remove the wheel and fix a puncture.

 

[Spiderweb]

You don't have to unbolt the derailleur to remove the wheel.

 

[Racing roadkill]

.

You did what now?

I suppose there's an inverse logic there somewhere. You'll find it easier to put the derailleur back on if the bike's upright. It just bolts straight back on. You will probably need to adjust the gears once the derailleur is back on. It's called 'indexing' there are plenty of good YouTube guides available.


View: https://m.youtube.com/watch?v=UH43OCmArUw


If you can release the wheel without removing the rear mech in future, it will make life much simpler for you.

 

[Ajax Bay]

You will probably need to adjust the gears once the derailleur is back on.

Why would you expect to have to re-index the gears? What has changed, once the RD is bolted back on? TMN to @Rickshaw Phil for the advice to leave the RD in situ when removing the wheel (and for being so quick to spot the nub of the issue and provide excellent photos illustrating the way forward/back).

 

[Cyclelover1997]

Did think it was just case of tightening bolt but can't seem to get the derailleur in shape to be able to get bolt into frame if that's makes sense??

Thanks for all advice given much appreciated ..

 

[Cyclelover1997]

Is there a video on how to put derailleur back on when removed it to fix puncture ?

 

[Ajax Bay]

Is there a video on how to put derailleur back on when removed it to fix puncture ?

No - because you don't have to (and shouldn't) remove it.
Endeavour. Maybe a second pair of eyes would help (for the avoidance of doubt, I mean getting someone else to help you, with @Rickshaw Phil 's images at hand.

 

[Spiderweb]

Did think it was just case of tightening bolt but can't seem to get the derailleur in shape to be able to get bolt into frame if that's makes sense??

Thanks for all advice given much appreciated ..

Have you removed the wheel before trying to refit the derailleur?

 

[Cyclelover1997]

No never, would be good if someone could do me a video showing how I would do it :-)

 

[Rickshaw Phil]

Ah, I'm not aware of any videos that show this operation. It's really straightforward though so I'll attempt to talk you through it:

Firstly here are another couple of photos which show the component parts of the derailleur clamp:



In the photos above the parts are: the shaped nut (left) the derailleur hanger (middle) and the bolt that holds the two together.

Take the wheel off the bike to start with then offer up the shaped nut on the inside of the dropout (the slot the wheel axle fits into). You'll see that the shape of the nut allows it to fit snugly into the curve at the end of the dropout.

Now offer up the derailleur to the other side. As shown in the right hand photo this clamp has a couple of pegs that slot into the dropout to help locate the hanger in the correct position. Next, put the bolt through the small hole in the hanger, screw it into the nut and tighten up (needs to be secure but not massively tight) making sure that the nut is still snugly in its position at the end of the dropout.

Refit the wheel. On the drive side the axle will locate in the hanger and the non-drive side will be roughly halfway along its dropout. Make sure the wheel is in line with the bike (you'll probably find there is a hole in the bridge between the chain stays which you can line up the centre of the tyre with) and tighten up.

If you haven't twiddled any of the adjusters while the derailleur was off, the gear indexing should be okay. If it isn't the video posted by @Racing roadkill should see you right.

I hope that helps. Give us a shout if you have difficulty.

 

[Cyclelover1997]

Find it difficult to understand all that, somebody doing a video on here showing how to do it would help a lot. Sorry to be a pain

Cyclelover1997

 

[Broadside]

Without wishing to be rude I think you probably need to take it in to a bike shop.

 

[raleighnut]

Find it difficult to understand all that, somebody doing a video on here showing how to do it would help a lot. Sorry to be a pain

Cyclelover1997

you need to fit the rear derailleur to the frame before the wheel is anywhere near the bike, once it is fitted as per the photograph posted by @Rickshaw Phil you can then think about re-fitting the wheel.

 

[youngoldbloke]

I think you would find it easy if you removed (split) the chain first - BUT if you're unsure about that too, (as I suspect) take it to a bike shop. It will take them no time at all to bolt it back on.