Shifting up sometimes requires two clicks

[shambolic]

Hi,
My gear shifter seems to need recalibration. I can shift down relatively consistently, but sometimes I need to click twice to take things up a gear on the rear derailleur (an 8 speed). It was working properly at one point, so I think it's just a question of adjustment.
Should I basically repeat the steps of the rear derailleur adjustment tutorial? And if so, is it a good idea to loosen (and then tighten)( the cable at the highest gear so that there really is no slack?
many thanks<br />
:-)

[Alex Ramon]

It sounds like a cable adjustment. Watch the <a href="http://bikeride.com/adjust-rear-derailleur/">derailleur adjustment video</a> at about 3:00 for some tips.
Yes, you can start by setting the cable on the highest gear so there is no slack and then work through the gears and adjust as needed.