i converted the wife’s bike today and she prefers it having never really got on with the front mech. 32 front with 11-42 e13 rear.

i remember reading a thread a while back (and i’ve tried looking for 15 mins) about people having the issue of back pedalling and the chain falling down the block – is there a fix other than not stopping in 42t – even if she just pushes the bike about maneuvering she is into a potential mech rippage off situation. i told her to not stop in the 42 and this seems to be reasonable mitigation (back pedalling to put the cranks in the right place to start does it too) but im interested to know how others have got on.

it’s an e13 one – is it a cross brand thing or are there makes which dont do it? or maybe i need a different chain – its an ‘xt’ 10sp one

edit add – it doesnt do it at all in any other gear, only the 42t

edit again – is it worth playing with spacers for chainline? i put the 32t front in the middle ring position

What’s the b tension looking like?
If the limits are right it should sit in the right place.

Generally it’s a chainline issue

tbh i was up against it time wise, i fitted everything, checked the indexing which seemed ok and off we went. so the top limit screw is more than likely wrong

i shall do some poking about tomorrow – i fitted the new e13 b screw. any tips for b screw setting?

The e13 ones are useless, mine did the same so did some research and found loads of people having the same issue.

Sent it back and got another oneup instead, now on the 4th oneup sprocket with no such issue

I played around with crankspacers and minimised this issue on my 1×11 setup. with the spacer on the correct side, it dropped down two cogs on only 180deg of back pedal!

I’ve got the same problem with SRAM X1 setup.
I know others have too.

Been told its because the alignment of chain and nothing can be done.

Yip.. chainline issue. I removed the spacer I had from the drive side and it was a ‘bit’ better. Can get 3 turns at the back before it drops down.. 😕

I’m only running 11 36 and have this issue.

managed to get it a bit better to the point that It doesn’t always happen by adjusting the spacers on the crank to bring the chainline in a bit.

only other option i see is to remove one of the black 2.5mm spacers from the drive side bottom bracket and fit it on the non drive side.

Ive give up worrying as it only happens in first gear.

i remember reading a thread a while back (and i’ve tried looking for 15 mins) about people having the issue of back pedalling and the chain falling down the block

Why are they jeffing back pedalling in the first jeffing place?!?!?!?!

i never EVER pedal backwards. EVER.
The only time you’re in the low gears you’re going to be going up a steep hill. Why would you suddenly start peddling jeffing backwards up a jeffing steep hill?

*slaps forehead*

Arrgggghhh.

Oh do be quiet ffs. Even pushing the bike around can make it fall off.

Yep, chainline. There’s some guff floating around that using a SRAM chain rather than KMC helps.

Un-scientific SRAM vs KMC test at home suggests it’s rubbish and the people who had success probably changed their chainline at the same time.

Only really noticed at home when I was indexing, when riding I didn’t seem to back pedal when in the 40T.

Re ‘Never back pedal’. Quite useful to help your legs warm leaning on a tree waiting for the start of a race or slower mates on a climb etc. Granted you don’t need to do it in the lower gears.

So you go up a steep hill in the 42 sprocket , have to get off half way up to open a gate , push bike through , shut gate , get back on and pedals are in the wrong position . Back pedal to get them in the correct position and suddenly the chain is in the middle of the casette . Not ideal in my view .