Sram x9 wont change into higher gears

[jab]

Hello all

I am new to mountain biking and have a problem with my rear deraileur. It is a sram x9 and it will not change to the two smallest sprockets on the cassette. I have tried adjusting the h screw to no effect. How can i fix this please?

Thanks

[Bill]

If you look above there are links to videos on how to trouble shoot and also learn stuff .

[davembk]

Hi jab,

I had Exactly the same and today I found out why....
It's not a problem with maintainance.....

Do this to show yourself what is going wrong......

Shift to the highest gear, i.e make the rear mech cable totally slack. Screw out the "hi" screw far enough to make it have no effect on anything. Take your wheel out, get a flashlight and have a very close look at the hard to see side of the mech, where the "lo" screw comes to bear. By hand, move the mech inwards, to the low shift position. Look at the lo screw, you'll see that it touches one side of the inside of the parallelogram, and therefore, correctly, prevents overshifting. Now, let the mech come right out again, towards the high shift position. You'll see that bizarrely, that same screw touches again. Basically, the lo screw restricts both low and high shifting simultaneously acting as both high and low adjusters. So we'll never properly get that high gear unless we wind out the lo screw, in which case we'll run the risk of over shifting to low, with the chain jamming in the spokes. There is a way out of this, file away some of the mech inner edge, where the lo screw bears, when the mech tries to go to high. But, why should we, this is a design fault. only just discovered this today so I'm still working out what to do, contact sram etc..How on earth did they make something like this?.....

Hope this helps,

Dave.