New Chain Woes

[Decho]

I’m having issues with a new chain(s) which I fitted to my Vado 4. It happens with both Shimano and KMC chains. I thought originally it might be because the Shimano chain was different from KMC(fitted when the bike was new), but fitting a new KMC chain causes the same problem
The problem is that under torque I get a grinding type noise from the rear derailleur. If I apply the brakes lightly when pedalling slowly it makes the noise and if I look back I can see and hear the tension pulley and cage rattling.
if I put the old chain on again, all is ok.
The old chain is fairly worn so I am wonderimg if something needs adjusting to accommodate the new chain?
Any advice appreciated.

 

[Stefan Mikes]

There are two ideas that came to my mind:

• You might have placed the new chain the wrong way inside the derailleur cage, or
• Your cassette cogs have got terribly worn out. Old chain fits the damaged cogs but the new one doesn't. It is the most probable cause of your trouble.

Because all chains for given number of speeds (for instance 10-speed chain for 10-speed cassette) and with proper number of chain links basically work the same way, is it KMC or Shimano.

 

[rich c]

You can adjust the derailleur cable tension by small amounts up at the shifter by turning the tension knob one way or the other. I have yet to establish a true method to decide direction, so I turn it a couple clicks one way while riding to see if it helps. If it gets worse, I turn it the other way. Small adjustments makes a big difference, so don't go wild with it. Also visual inspect to make sure the hanger isn't bent. How many miles on the bike? How much stretch on the old chain and was that the original?

 

[Decho]

You can adjust the derailleur cable tension by small amounts up at the shifter by turning the tension knob one way or the other. I have yet to establish a true method to decide direction, so I turn it a couple clicks one way while riding to see if it helps. If it gets worse, I turn it the other way. Small adjustments makes a big difference, so don't go wild with it. Also visual inspect to make sure the hanger isn't bent. How many miles on the bike? How much stretch on the old chain and was that the original?

 

[PedalUma]

Chains, jockey wheels, cassettes and chainrings wear together. Changing one of these with out changing the others will make for worse problems because the new component will not mesh with the others and will cause skipping. If chains are regularly changed before they are worn beyond spec this problem can be largely avoided or postponed.

 

[Decho]

The gears change ok. It’s the original chain which had stretched and was in need of replacement.
I’ve done about 2000miles since new on the original chain - I should have replaced earlier but I’m learning bike mechanics as I go along. I was wondering whether adjusting the B screw might solve the problem?

 

[Decho]

I’ve also had the rear cassette changed but that made no difference.

 

[PedalUma]

It could be any number of things. For example the derailleur may have been bumped. This would happen to me on the train and it is one reason to install an IGH on commuter bikes. If it was bumped you will need a DHAG to straighten the hanger. A minor twist will throw off alignment and cause a similar problem to your description.

 

[Kless]

I had exactly the same problem when I put a new chain on my Como 3. Turned out that it was the front chainring that was worn and wouldn't mesh properly with the new chain. They demonstrated the problem in the bike shop by putting the bike up on the stand, and then peddling while applying pressure to the rear brake. Could see the chain not wanting to release from the chainring, and the bottom of the chain would jump up and down, making a very weird grinding type noise. I too initially thought it was something with the derailleur, but once I had the chainring replaced, all was good.

 

[Decho]

I had exactly the same problem when I put a new chain on my Como 3. Turned out that it was the front chainring that was worn and wouldn't mesh properly with the new chain. They demonstrated the problem in the bike shop by putting the bike up on the stand, and then peddling while applying pressure to the rear brake. Could see the chain not wanting to release from the chainring, and the bottom of the chain would jump up and down, making a very weird grinding type noise. I too initially thought it was something with the derailleur, but once I had the chainring replaced, all was good.

Thanks, that sounds like my next step then. I did find it strange that my LBS thought to change the rear cassette but not the Chainring. Will need to see if this is something I can do myself as I’m trying to learn as much about maintenance as possible, but I’m not sure if I need to remove the crank to do this?

 

[Stefan Mikes]

Thanks, that sounds like my next step then. I did find it strange that my LBS thought to change the rear cassette but not the Chainring. Will need to see if this is something I can do myself as I’m trying to learn as much about maintenance as possible, but I’m not sure if I need to remove the crank to do this?

You don't need to remove the crank on most of Specialized e-bikes. It is enough to remove the pedal so it is not in the way of the chainring on the swap.

 

[Decho]

I had exactly the same problem when I put a new chain on my Como 3. Turned out that it was the front chainring that was worn and wouldn't mesh properly with the new chain. They demonstrated the problem in the bike shop by putting the bike up on the stand, and then peddling while applying pressure to the rear brake. Could see the chain not wanting to release from the chainring, and the bottom of the chain would jump up and down, making a very weird grinding type noise. I too initially thought it was something with the derailleur, but once I had the chainring replaced, all was good.

Perfect solution thanks! I ‘borrowed‘ the chainring from my wife’s newer Vado and put it on mine and the bike works perfectly now….noise and vibration gone. It’s an easy job, just 4 bolts and the ring comes off without removing anything else.
i just need to get a new one on my wife’s bike quick before she finds out!
Another lesson learned…I will keep a close eye on chain wear in the future. I’m actually really enjoying learning about bike mechanics

 

[EMGX]

Something to consider is that your bike might have a narrow/wide chainring. If so, and if you weren't aware of it, then you have a 50% chance of putting the chain on the chainring with the wrong links lined up - which would result in what you and Kless described.
I read a lot about worn chain and sprockets on relatively low mileage bikes. I just went out and measured the chain on my bike with a Yamaha PW-SE mid drive and 11 speed chain. It and the chainring/sprockets show virtually no stretch/wear with ~2,000 miles of riding of which most rides include a couple thousand feet of steep climbing so the drivetrain must be relatively stressed but still not significantly worn.

 

[Decho]

Something to consider is that your bike might have a narrow/wide chainring. If so, and if you weren't aware of it, then you have a 50% chance of putting the chain on the chainring with the wrong links lined up - which would result in what you and Kless described.
I read a lot about worn chain and sprockets on relatively low mileage bikes. I just went out and measured the chain on my bike with a Yamaha PW-SE mid drive and 11 speed chain. It and the chainring/sprockets show virtually no stretch/wear with ~2,000 miles of riding of which most rides include a couple thousand feet of steep climbing so the drivetrain must be relatively stressed but still not significantly worn.

I fell into this trap earlier on …another learning experience!
But it’s definitely the chainring at fault here.

 

[Decho]

Went for a 30 mile ride today with the newer chainring(from my wife’s bike!) installed and what a difference it made, even the gear change was smoother.
wemt to the LBS this afternoon and they can’t source a Praxis 40T chainring anywhere so they have ordered a compatible (steel) ring from Specialized.

 

[DDBB]

I bought the park tools chain wear tool as I didn't trust the cheap tool I had that only measured for .75% and 1.0%.. After 2,000mi. (haibike trekking 6.0, yamaha PW, 10 speed cassette) I'm not even at .5% yet. I do clean and lube the chain every 100mi. (or sooner if it gets wet or I ride dirt roads). I've been using Maxima chain wax which is what I use on my huge 530 motorcycle chain. It's really thick stuff and I don't think any bike shops use it but the lube is infused with paraffin (as I understand it) so when it dries there's a waxy surface texture which helps seal in the lube. I get 30,000mi. out of a motorcycle chain on a bike that has 135 HP but the motorcycle chains are 0-ring chains, I think it'd be great if that option was available for e-bike chains but probably isn't done because of the weight and the narrow nature of the chain for our ebikes. I have a replacement chain for my Haibike already because I thought it might be worn out after 1,000mi. but now I think it might go 3,000mi. I searched and can't find any specs on my e-bike to tell me if it has narrow-wide chain ring. Is there a way to tell by looking at the chain ring? EDIT: Found an article w/ pics on narrow/wide chain rings. Inspected mine and it's a standard chainring. Since I have a double chain ring up front it has to be