It'll shift up from small to large chainring but when i drop it down again in the smallest cog at the back it dumps the chain onto the spider rather than the small chainring.
Jump up the cogs at the back will pull it across enough and engage it fully again.
Any ideas?
do you mean it's dropping between the 2 chainrings?
If so, I imagine it's the thinner chain buggering things up - esp if it's a really old chainset
How do the rings fit on? If there are spacers, could you grind/file them a bit to make the rings sit closer to each other?
Or am I misunderstanding ?
Yeah I'm pretty confident its the chain width.
No spacers unfortunately they just sit either side of the spider.
Its a ballache
would you be happy grinding down tabs on the spider?
... why are you shfting to the smaller ring when you're in the smalles rear cog?
Well something like a 8spd or 9spd chainset won't work with an 11spd chain. You will get the chain dropping between the chain rings as you described. Time for a new chainset.
why are you shfting to the smaller ring when you're in the smalles rear cog?
Well its not something one does but it should work or you run the risk of binning it if you make mistake.
So is an 11 speed chainset more closely spaced to compensate?
Update:
One dremel one + one dremel router attachement + alot of measuring and one old chainring used as a testbed = one thinner chainring.
Longevity might be an isdue but it shifts beautifully just now.
Whatelse can i ghetto mill...
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