chains and gear stuff

[Electric_Andy]

Hi all - I've just got back on my partners' Trek 7.2 (I think) hybrid. It's been sat in a garage for about 8 years, apart from 2 years ago when I oiled and set it up for a one-off ride. The (8spd) gears are now slipping quite a bit. My question is, the cable seems too short now - as in it won't let the cage down to the smallest cog at the back. Is it normal for them to "shrink" whilst sitting? I always assumed they would stretch or just remain the same if unused. I have run out of adjustment at the handlebar mount so I guess I either create or delete some slack at the rear end at the derailer?

Secondly - does anyone know of a quick ready-reckoner of how to set the seat and bar heights/angles? I can do trial and error but maybe there's a good guide somewhere that won't involve hopping on and off multiple times? I have no suitable garden to ride around, so have to do it on the road.

Thanks,

 

[Paulus]

The cables don't shrink, but as it has stood for years it may of corroded or frayed inside the outer cable.
Best thing is to get the shifter into 8th and try to pull the cable through and see if the rear mech moves over. It may be just a case of some corrosion inside the cables or maybe the mech and cables need a bit of a lube.

As a rough guide to saddle hight, adjust the saddle so that when seated, put you heel on a pedal at the six o'clock position. Your leg should now be more or less straight. With the ball of your foot on the pedal your knee should be slightly bent around 30⁰