Got a MARIN BOLIAS RIDGE,gears sligtly missing just have to go dwn 1 thn back up to hit right on .
Question is it a case of just tensioning cables a bit more ,
Shimano Alivio rear mech ,hyperdrive frnt mech .2007 model.
suggestion s plz
Assuming that your mech isn't badly worn/bent/misalingned....
Drop the chain onto the middle ring.
Drop the chain onto the smallest cog on the cassette (yeah I know I called it a cog and it isn't strictly a cog).
Make sure your shifter has no clicks left in it by pulling on the cable and clicking it.....
Now shift up one click.
Turn your pedals.
If the chain doesn't shift up one gear adjust the barrel adjuster on the cable until it does.
Et Viola! That should be it.
SB
[url= http://www.parktool.com/repair/byregion.asp?catid=53 ]THIS[/url] would be a start...
Worn Cassette
Worn chain
Worn mech(s)
Worn shifters
Worn Cables
Incorrect adjustment (indexing/cabling etc)
Could be a lot of things but I'd start with a visual inspection, hooked teeth on cassette/ chainrings, make sure its indexing correctly, shifters are operating ok, mechs pivots are not sloppy, cables running freely.
Good luck!!
Have a look at parktool.com - they have explanations on how to fit/adjust pretty much everything on bikes including what you're asking.
Take a look at this video:
worth checking b-tension
put in middle cog + largest sprocket then loosen b-tension screw until rear mech gets close to largest sprocket.
