Lovacott
Über Member
This has never happened to me before, but on the way home on Monday night, my drivetrain seized solid as I changed down to the smallest chainring on the way up a very steep incline (I changed down whilst I had good momentum so I wasn't loading the drivetrain).
I walked the bike the rest of the way up the hill and popped the chain back onto the middle ring and completed my journey.
When I got in, I suspended the rear wheel and went though every gear combination trying to figure out what had happened.
The only gear combo which gave a hitch was small front to small rear which caused the chain to wrap around and back up the front chainring until it jammed against the section of chain feeding into the top of the chainring.
I've tried everything this week to put it right.
I've re-indexed both the front and back from scratch, thoroughly cleaned and oiled everything, checked the chain for deformities, checked the alignment of everything.
What puzzles me is that I have never had this problem before, I had ridden without incident for the ten miles into work and most of the way home, but then this suddenly happened?
Over the last four days I have put quite a few hours into this and last night, I thought I'd cracked it. But, lo and behold, the same thing happened tonight on the way home.
One thing I have noted is that when the chain is on both of the small rings, there is a noticeable sag in the chain and I wondered if maybe my rear mech is not providing enough tension to the chain, therefore allowing it enough slack to ride up the front chainring?
Any thoughts would be welcome.
I walked the bike the rest of the way up the hill and popped the chain back onto the middle ring and completed my journey.
When I got in, I suspended the rear wheel and went though every gear combination trying to figure out what had happened.
The only gear combo which gave a hitch was small front to small rear which caused the chain to wrap around and back up the front chainring until it jammed against the section of chain feeding into the top of the chainring.
I've tried everything this week to put it right.
I've re-indexed both the front and back from scratch, thoroughly cleaned and oiled everything, checked the chain for deformities, checked the alignment of everything.
What puzzles me is that I have never had this problem before, I had ridden without incident for the ten miles into work and most of the way home, but then this suddenly happened?
Over the last four days I have put quite a few hours into this and last night, I thought I'd cracked it. But, lo and behold, the same thing happened tonight on the way home.
One thing I have noted is that when the chain is on both of the small rings, there is a noticeable sag in the chain and I wondered if maybe my rear mech is not providing enough tension to the chain, therefore allowing it enough slack to ride up the front chainring?
Any thoughts would be welcome.
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