Not common here. Are you using a boost chainring?
Chain drops from largest cog down when backpedaling, due to angle of 1x11, why?
After searching, only could find older posts, perhaps prior to the 1x11/12 drivetrains, like from 2004 and 2006.
Obviously when in highest gear and being the farthest angle, the chain guides itself off the large cog and goes down. No, I don't pedal backwards, but often we set out crank in a certain position and backpedal to do that, and, walking the bike backwards just a few inches, same effect. So, is this just the way it is, is this normal for brand new chain/drivetrains??
Obviously when in highest gear and being the farthest angle, the chain guides itself off the large cog and goes down. No, I don't pedal backwards, but often we set out crank in a certain position and backpedal to do that, and, walking the bike backwards just a few inches, same effect. So, is this just the way it is, is this normal for brand new chain/drivetrains??
1 - 20 of 36 Posts
On some bikes it happens. Sometimes it depends on the position of the cassette, or on how worn it is.
On my Grand Canyon AL SL 8.0 with a 12sp SLX cassette it happens on the biggest cog when the cassette has some wear in it, although it's still perfectly usable. It doesn't happen with brand new cassettes.
It's crap when trying to start on a hill and the chain falls while I position the pedals. To be honest, I think the whole 1x is crap, but I think that can't be said around here.
On my Grand Canyon AL SL 8.0 with a 12sp SLX cassette it happens on the biggest cog when the cassette has some wear in it, although it's still perfectly usable. It doesn't happen with brand new cassettes.
It's crap when trying to start on a hill and the chain falls while I position the pedals. To be honest, I think the whole 1x is crap, but I think that can't be said around here.
Not knowing the specifics of your bike, its hard to say why you could be having an issue. Need to know if you are running a Boost/non Boost frame, chain stay length, drivetrain details, etc.After searching, only could find older posts, perhaps prior to the 1x11/12 drivetrains, like from 2004 and 2006.
Obviously when in highest gear and being the farthest angle, the chain guides itself off the large cog and goes down. No, I don't pedal backwards, but often we set out crank in a certain position and backpedal to do that, and, walking the bike backwards just a few inches, same effect. So, is this just the way it is, is this normal for brand new chain/drivetrains??
I have been on Shimano 1x11 since it came out. Four different frames with various combinations of SLX, XT, XTR and Wolftooth. The only times I had backpedaling issues was when I needed to adjust the derailleur, had failed to space the bottom bracket correctly and once when I set the chain length too short. All were quick fixes. Other than that, no backpedaling issues what's so ever.
I have not made the move to 1x12 and don't plan to, 1x11 gives me the range I need for my area and it works great.
Very common, try adding a very small amount of cable tension.
When backpedalling the chain that derails is the one at the top of the cassette. The derailleur is at the bottom and has nothing to do with it.Very common, try adding a very small amount of cable tension.
Boost- yes, chainstay- 425mm, all shimano deore. Only comes off of top two largest sprockets, 10/11.
How much back pedaling do you do? I have the 1x12 SRAM on my EPIC and if I back pedal multiple revolutions, it can slip off of the large ring. On the trail, I am rarely in the large ring and I can't think of a situation where I would back pedal more than 90 degrees.
Right, same here, i only need to backpedal maybe half turn to sometimes set pedal or raise to avoid large rocks. But it does start to come off pretty quick. With such an angle, i really dont see a fix. But i wont give up.
oh, i’m not in that granny gear often either, only steep climbs like this.
![Bicycle Cloud Slope Bedrock Sky]()
oh, i’m not in that granny gear often either, only steep climbs like this.
You said it here, so evidently it's possible.To be honest, I think the whole 1x is crap, but I think that can't be said around here.
Personally I'd rather suffer an occasional backpedal derail on a 1x system than suffer the multiple negatives that come with front derailleurs but this is a matter of personal choice.
To each their own. Stand proud. It's okay when peoples' personal experiences differ.
As for chains unshipping while backpedaling or rolling the bike backward on 1x drivetrains, yeah, it can happen.
Modifying chainline -- that is, reducing chainline -- usually helps.
I believe "standard" chainline on 1x drivetrains these days is 55mm but I don't pay a lot of attention to whatever it is.
Every bike is different so I work with each bike individually to see what can be done to minimize chainline.
Whenever possible, I reposition BB spacers to move the chainring as close to the chainstay as possible without the ring actually contacting the stay.
Move BB spacers from the driveside to the non-driveside. Thin & thinner BB spacers are available aftermarket to fine tune.
If anyone reading actually tries this, position the ring no less than a couple mms away from the stay. Make sure there's clearance throughout the crank's rotation.
Running a smaller chainring makes it easier to improve chainline because it'll afford more room between the ring and the stay.
On most bikes it's possible to improve chainline by a few mms over stock which helps reduce the backpedal unshipping phenomenon.
=sParty
That's a "feature" of wide range 1x, starting at about 11spd. There's some variability in how much a given bike does it that depends on chainline, chainstay length, etc. But it's here to stay.So, is this just the way it is, is this normal for brand new chain/drivetrains??
From what I've seen, most 12spd drivetrains reduce it some compared to 11spd, but don't completely get rid of it. My Shimano 12spd also didn't do it when brand new, but started doing it after the drivetrain got a bit of wear in it. It mostly doesn't affect anything for riding, but occasionally does happen when I try to position my pedals and get a start on a climb.
Of course i do have the one spacer on the drive side and none on the left, which they gave me the extra one, i believe is for a 68mm and mine a 73mm BB. I wonder if i put the one spacer only on the left side??
It probably won't make as much of a difference as you want it to.Of course i do have the one spacer on the drive side and none on the left, which they gave me the extra one, i believe is for a 68mm and mine a 73mm BB. I wonder if i put the one spacer only on the left side??
My 1x11 Box One system never did it and my 1x12 Deore system never does it. Something is out of adjustment or worn. Not a “feature” of current and property adjusted 1x drivetrains. How many miles on it? When was the lastbtime you changed the chain? What chain are you using?
It absolutely is an extremely common aspect of 1x drivetrains. There are many reasons why it happens, and the bike frame definitely matters.My 1x11 Box One system never did it and my 1x12 Deore system never does it. Something is out of adjustment or worn. Not a “feature” of current and property adjusted 1x drivetrains. How many miles on it? When was the lastbtime you changed the chain? What chain are you using?
For sure, probably 1/2 my 1x drivetrains have done this, especially shimano.
All brand new, KMC chain.My 1x11 Box One system never did it and my 1x12 Deore system never does it. Something is out of adjustment or worn. Not a “feature” of current and property adjusted 1x drivetrains. How many miles on it? When was the lastbtime you changed the chain? What chain are you using?
A chain can only go so far one way until it drops, or goes up..to the next cog. The largest cog is obviously at it's farthest angle form the front crank sprocket. Thus, it must be extremely common. All my shifting is good.
stand by: let me check my high screw adj. It could be too far.... (the "B" screw was)...... BTW, this bike is still at factory settings. Amazing how many little adjustments I have been doing...
stand by: let me check my high screw adj. It could be too far.... (the "B" screw was)...... BTW, this bike is still at factory settings. Amazing how many little adjustments I have been doing...
I see it happen more often on short chain stays, also as your chain wears it allows more sideways flex and less likely to drop down as much. Changing the BB spacers to the left side can help as long as your chain ring has good clearance to the frame. Every bit helps, but some set ups are more prone to the problem than others, it's just one of those things.
1 - 20 of 36 Posts
- This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Mountain Bike Reviews Forum
A forum community dedicated to Mountain Bike owners and enthusiasts. Come join the discussion about bike parts, components, deals, performance, modifications, classifieds, trails, troubleshooting, maintenance, and more!
Full Forum Listing
Explore Our Forums
Top Contributors this Month
View All
ilmfat
831 Replies
DIRTJUNKIE
473 Replies
Sparticus
399 Replies
Recommended Communities
