This chain sucks.
12-07-20, 09:33 AM
#1
Newbie
Thread Starter
Join Date: Dec 2020
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
This chain sucks.
I'm in the southern UK. I have a Cube Kathmandu on which I've done about 4K miles. Unfortunately I bought this bike from a local retailer who claimed to be a Cube agency. However this company (50Cycles) upped and disappeared overnight without so much as an email to their customers. So, if you're in the UK and thinking of buying from them I'd suggest choosing a reputable company instead.
Anyway...
Having plenty to do already I had someone locally do a basic service on the regular bike components including a new chain and tyres. He fitted what was supposed to be an "e-bike compatible" chain (double the price) for my Shimano Deore 10 speed system. However when I tried to ride away the crank repeatedly jammed up. This proved to be caused by what the guy described as "chain suck" (new concept to me) where the chain rides up onto the lower half of the crank sprocket. This doesn't happen when the drive train is operated on the bike support, only when under load on the road
My suggestion was to temporarily re-fit the old chain - which was in reasonable shape - and of course this "solved" the problem. The new chain was to all intents correct in all respects without any tight links or any other obvious problem. So I'm back on the old chain and puzzled.
Anyone familiar with this problem?
Also, if this forum has much UK reach I could post a general report on this bike, along with the disgusting total absence of support from the German parent companies Cube and Bosch.
Here's hoping...
Roy
Anyway...
Having plenty to do already I had someone locally do a basic service on the regular bike components including a new chain and tyres. He fitted what was supposed to be an "e-bike compatible" chain (double the price) for my Shimano Deore 10 speed system. However when I tried to ride away the crank repeatedly jammed up. This proved to be caused by what the guy described as "chain suck" (new concept to me) where the chain rides up onto the lower half of the crank sprocket. This doesn't happen when the drive train is operated on the bike support, only when under load on the road
My suggestion was to temporarily re-fit the old chain - which was in reasonable shape - and of course this "solved" the problem. The new chain was to all intents correct in all respects without any tight links or any other obvious problem. So I'm back on the old chain and puzzled.
Anyone familiar with this problem?
Also, if this forum has much UK reach I could post a general report on this bike, along with the disgusting total absence of support from the German parent companies Cube and Bosch.
Here's hoping...
Roy
12-07-20, 11:02 AM
#2
Senior Member
Join Date: Jul 2014
Location: socal
Posts: 4,256
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 878 Post(s)
Liked 813 Times
in
614 Posts
Always thought it was a function of worn chain/cassette rings not "separating" as the crank revolved because the worn parts "stuck" allowing the chain to get caught between the front chainring and chainstay. I'll bet if you install new cassette gears with the new chain the problem will go away.
12-07-20, 01:30 PM
#3
Senior Member
Chain suck can happen, but it's usually caused by excessively worn chainrings, which seems a little unlikely.
Most likely it's a KMC chain, it may have something on the side plates indicating the model. On the stand, run it through a lot of revolutions, and in particular check the quick link. A sticky link or burr on the link can cause unpredicatble behavior.
How worn was the original chain? If you have the chain, hang it vertically, and measure 12 links. The center of pin would should be 12in. A slightly worn chain would be 1/16in over, 1/8in would be very worn, and anything beyond 1/8in has probably trashed your entire drivetrain.
Ebikes are harder on chains. It's unlikely but a combination of not keeping the chain oiled, high mileage (4k) and high motor usage could cause a lot of chain wear. If that's the case, you potentially need a new chainring & new cassette.
Most likely it's a KMC chain, it may have something on the side plates indicating the model. On the stand, run it through a lot of revolutions, and in particular check the quick link. A sticky link or burr on the link can cause unpredicatble behavior.
How worn was the original chain? If you have the chain, hang it vertically, and measure 12 links. The center of pin would should be 12in. A slightly worn chain would be 1/16in over, 1/8in would be very worn, and anything beyond 1/8in has probably trashed your entire drivetrain.
Ebikes are harder on chains. It's unlikely but a combination of not keeping the chain oiled, high mileage (4k) and high motor usage could cause a lot of chain wear. If that's the case, you potentially need a new chainring & new cassette.
12-07-20, 03:54 PM
#4
Ride more, eat less
Join Date: Feb 2007
Location: Philla PA, Hoboken NJ, Brooklyn NY
Posts: 2,070
Bikes: Too many but never enough.
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 713 Post(s)
Liked 733 Times
in
450 Posts
It's not uncommon to replace chain with cassette or chainring; brand new chain is not exactly fitting of the old, worn chainring or cassette.
Likes For cat0020:
12-07-20, 05:30 PM
#5
Senior Member
Join Date: Jun 2020
Location: Maryland
Posts: 1,379
Bikes: 1982 Bianchi Sport SX, Rayleigh Tamland 1, Rans V-Rex recumbent, Fuji MTB, 80's Cannondale MTB with BBSHD ebike motor
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 667 Post(s)
Liked 529 Times
in
355 Posts
Your old chain is worn out, it is longer than it should be, that is why it fits into the worn chainring, i.e. they are farther apart than they should be, without getting stuck. They have worn together
In all likelihood the problem isn't the chain, it is your worn chain ring. Replace it.
If you continue to ride with the worn chain it is only a matter of time before it breaks.
Highly recommend buying a $7 chain checker tool and replacing the chains before they become too worn. Ebikes wear chains more quickly.
In all likelihood the problem isn't the chain, it is your worn chain ring. Replace it.
If you continue to ride with the worn chain it is only a matter of time before it breaks.
Highly recommend buying a $7 chain checker tool and replacing the chains before they become too worn. Ebikes wear chains more quickly.
12-13-20, 08:05 PM
#6
Senior Member
I bet you didnt get a 10 sp chain for your replacement.
-SP
-SP
12-16-20, 09:35 PM
#7
Senior Member
Join Date: Aug 2009
Location: New Jersey
Posts: 85
Bikes: Mongoose passed on to my son, Miyata, Tailwind, V-Rex, De Rosa, Safari, just added a Bike Friday
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 0 Times
in
0 Posts
Had the same problem on a new bike. Chain would ride up the lower half of chain ring and jam between the chain ring and the chain stay. The chain felt sticky when handled. Finally solved it by removing the chain then soaking it in solvent multiple times. Then drying and lubing the new chain.
12-16-20, 10:42 PM
#8
Senior Member
Join Date: Jan 2020
Posts: 2,347
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 680 Post(s)
Liked 947 Times
in
554 Posts
4000 miles or kilometers? 2500 miles is a good lifespan on my bosch powered bike the last chain I got 3000 with weekly wipe downs and lube. but but I usually get about 2500 miles. but it depends on what level of assist you use and how much you shift. I have had the chain jump off but its usually when the chain is worn.
