B-bolt for X.0 rear mech (9 speed)

Shaggy_Dog

Last summer I was riding in the Brecon Beacons and my mech hanger snapped off quite randomly, I'd given it a bit of a shunt on it's maiden ride which knocked the gear cable clean out of it's bolt but didn't appear to have affected the hanger (I tested it with a hanger alignment tool), being a numpty I frogot to pack a spare hanger so had a long walk back to the carpark, I've replaced it and now always carry a spare.

However, since the Beacons episode my gears have been somewhat sloppy despite my best efforts with limit screws and indexing, being a numpty yet again I failed to notice until today that the B-tension bolt was bent on the head end of the bolt (I.E. - before it threads into the dreailleur body) and snapped off as soon as I touched it. I'm assuming this is the cause of my headaches as the B-tension looks way too slack.

I have two questions, firstly -

Is the derailleur body threaded or is the plastic sleeve threaded (like the limit screw bodies)? The top of the plastic boot/sleeve/whatever has come off too. I don't want to unthread the stump as the bike is rideable at the moment, if there is a long wait for a new bolt I'm withoout a bike in this glorious weather

If so, is it a "normal" (M3, M4 etc.) bolt or does it have unique thread pitch therefore meaning I have to buy the Sram replcement bolt (£25!)

Thanks in advance lovely mountain bike people

nicklouse

to sum up. as there are lots of words and it is not that clear.

what is the thread on the B screw adjuster?

and which part has the female thread for the B screw the mech or the bit of plastic?

Shaggy_Dog

Yeah, thanks!

On a side note, as the bolt has to be screwed out to increase B-tension. I managed, through much trial and error to carefully wind out the bolt (thereby increasing b-tension/chain wrap-around) by removing the mech and carefully winding the bolt out using some miniature round nose pliers. I will at some point replace the bolt properly.

Unfortunately this doesn't seem to have remedied the situation much, I think the (brand new) hanger or god forbid - the frame - must be slightly bent