Problems fitting XTR M971 SGS Rear Mech

dan1502

I bought this unused but second hand and fitted it to my last bike (only on a few rides) and think I might have had the same problem then but it worked so I left it.

Anyway I'm now fitting it to my wife's bike.

The problem is with the B-Limit adjustment. WIth this type the screw presses directly against the mech hanger to limit the movement however even with the screw all the way in, the limit is not sufficient to stop the jockey wheel contacting the cassette.

I've checked the hanger and it looks fine and I also have another frame with the same hanger and that looks the same.

The XT shadow mech works fine.

I tried a longer screw but although it works, it's not the answer as it doesn't contact squarely with the hanger due to the length/angle when screwed that far out.

I've successfully fitted mechs several times so think there must be something wrong. Any ideas?

nicklouse

lets have some pictures.

dan1502

I'll struggle with pictures for now as if I go back to the bike right now a divorce will be on the cards!

If there's nothing obvious without pictures I'll sort some as soon as I can.

Thanks.

nicklouse

it should work fine.

so there is something wrong with it or the bike.

dan1502

The most obvious thing would be a bent mech hanger although I guess the mech could be bent near the stop area but neither appear bent. I'll try and get photos but otherwise might take it to BETD/Goldtec to check as they stock hundreds of hangers and know their onions. It still shifts fine though.

nicklouse

what size is the big cog on the cassette?

dan1502

34 but the mech is long cage so should be ok

nicklouse

just checking.

dan1502

I'll probably try removing the hanger from the other frame and checking them right next to each other.

dan1502

Ok,l so I checked the hanger and it's fine. But, I measure the cage length and it's 3.5 inches whereas the XT shadow is 4inches. I think despite having SGS on the box, I've been sold a GS mech!

That's the second time this has happened now. Someone sold me some 685mm EC70 bars that were described as riser but they're flat.

nicklouse

cage length should not effect how the B screw works unless you are in a gear combo that is pulling the mech up.

cooldad

The length of the mech doesn't change the position of the top jockey wheel.

dan1502

I'm having one of those days today. I decided to just put the XT Shadow mech back on for now and then noticed some play in the cassette. Anyway it's side to side play in the freehub. I'm not sure if this can be solved and I think these wheels are awkward to work on as they're FSA XC290s.

Anonymous

nicklouse wrote:

lets have some pictures.

+Potato

dan1502

I'm at the stage that if there isn't a way of getting rid of the play in the freehub then I will have to get a new freehub or new wheelset. I don't know how you remove the freehub on these wheels and there doesn't seem to be any guides on the FSA website. I suppose even if I did get new wheels it would be good to get these going again to recover some money selling them on.

The thing is these were on my hardtail which I've split and sold and I'k pretty sure the problem's only arisen on changing cassettes over. I've now sold the two other sets of wheels I had so am a bit stuck.

Unless you can tell me how to sort the freehub or something to check, I think it will be over to the bike shop.

dan1502

I have just taken one bearing out and removed the axle and looking through, it would seem a large splined key is required to remove the freehub (12mm??) which I don't have.

So, one fundamental question. Does side to side play in a freehub mean it's mullered?

nicklouse

maybe. depends on how it works.

Pics.