9 out of 10 times when your gears are misbehaving it's sticky cables.As I've mentioned before it's best to replace the cables with full outers,but if you cant be bothered this is a good way of keeping them shifting smoothly.
This one is really easy.You dont need any tools,just some of your favourite lube and some tissues.Ahem.
First start with your rear mech in the top position on the largest rear sprocket. I'm assuming you dont have an opposite 'low normal ' setup.If you do, start on the smallest sprocket.The principle is the same.
You now need to release the tension in the cable.Do this by changing gear at the shifter ,but DO NOT TURN THE PEDALS.
As you click down the inner cable becomes slack. You might need to pull on the exposed inner to help it to release .
Now all the tension is released you can unhook the cable outers from the guides in the frame.
Use your imagination for this bit.It will depend how gummy your cables are. Use copious amounts of your fave lube.You can pull the caps off the cable outers to squirt inside the cables a bit.Quickly slide the outers back and forth along the inners and wiping them as you go . If the inners are actually rusty you should replace them,BUT,if you were a mingebag you could maybe clean them with wire wool or something just a bit abrasive.While youre at it,look inside the guides for dried in bits of cack.
If you have disc brakes be careful with spray lube.If it gets on the brake pads it can knacker them.
When you are satisfied that the cables are OK ,lube them up with light bike specific oil,and hook them back in the cable guides.In a classic Haynes manual style ,refitting is a reversal of removal.Take care not to kink the inners as you feed them back in and if you are struggling to get the last one in ,check that the mech/chain hasnt slipped down a cog or two at the back. If it has ,push the mech ,BY HAND, and slot the chain back on the top sprocket.Dont touch the shifter or the pedals until you have all the cables back in the frame guides.When it's all back in ,take up the slack in the inner by changing gear at the shifter,or turning the pedals.
Do the front mech as well. The principle is the same.Start on the top sprocket,dont pedal,change down the gears to the granny ring,unhook the outers etc etc.
Step7.When you have finished bask in the glory of what you have acheived. I celebrated with a nice latte,but you might prefer something else ,maybe a nice cup of 'Earl Grey'.
This is such a quick fix I have even done it mid-ride to cure troublesome shifting.Prevention is the best medicine though ,so do it regularly and definitely after a wet ride.It works equally well on racing bikes too,in fact ,any bike with slotted cable guides,and derailleur gears.
No featured lyrics today,but I was listening to 'Bloc Party' with their obscure references to Brett Easton Ellis.This didnt affect the outcome of the job in anyway and in fact nobody was butchered in a horrific satire on the overbearing wastefulness of the eighties, although the sky did exhibit a certain 'hazy shade of winter'.Haha