Bicycle Tutor

I have a raleigh mountain bike which uses gripshift.
My problem is that I think something in the right gear changer has shifted, because it won't go below halfway on the dialer but the bike recognizes that as being in first gear as opposed to second which is what it should see it as, and it reaches as far as what used to be third gear on the dialer but the bike only goes as high as second gear. I think it would go up to third if the dialer went higher, but it only moves between half way and the top.

Sorry I don't know any technical jargon, but I hope that made some kind of sense and if you could help I would be so appreciative!!

sounds like the cable needs to adjusted.

need some pictures.

is this a derailleur or IGH ?

Have you changed anything on the bike or did it just stop working?

My immediate thought is that your shifter and derailleur are mismatched. SRAM (the makers of gripshifts) sells two varieties of shifters/derailleurs: 1:1 actuation (usually named X2.0, X3.0, etc.) and 2:1 actuation (usually labelled MRX Compatible). You can read more about actuation ratios here:

http://en.wikipedia.org/wiki/Derailleur_gears#Actuation_ratio

If your derailleur uses 2:1 actuation (i.e., it's Shimano-compatible) but your shifters use 1:1 actuation (i.e., it's an SRAM X3.0, X4.0, etc.), the derailleur will only move half as much as it's supposed to.