Question on 'dropped chain'?

You probably don't notice it but the chain is probably coming off the rear cassette first and then it jumps loose off the front ring. Since it happens in the blink of an eye and you're likely looking forward while cycling. The chain may even bounce back onto the rear cassette so it seems as though it came off the front ring initially and that falsely appears to be the root cause. Most narrow/wide front rings , Lekkie is a fav of mine, for ebikes rarely if ever pop off the front ring alone.


How do you shift gears uphill?
In my experience if I happen suddenly upon a very steep hill and I happen to be in the highest to high gear, I get off my bike ,lift up the rear wheel and shift to the lowest gear. Then get back on and climb the hill only in that gear. Then when I get to a flat portion I'll shift higher. You should never really be shifting uphill into higher gears on mid-drives up hill.
 
I'm here, wassup?
First of all, I wanted to say "Hello" to you, as I can see you mostly on Strava, zooming your Vado almost everyday!

Secondly, you are the OP there, and you initially had issues with chain dropping on your Vado. How can you see it in the perspective of several months of your Vado riding?

Thirdly, a gentleman here claims he cannot lock the derailleur cage on his SRAM Horizon NX derailleur. I was wondering what was that button for?
1680238288720.png


BTY, saw a 6.0 Tero X today, I'm drooling!
Oh you! :)
 
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The button highlighted is to lock the cage out of the way to take the wheel off. SRAM call it cage lock.


At first I assumed it was a button to turn the clutch on and off but it's simply to hold the cage out of the way. Therefore I understand why anyone else would assume that it operated like the on/off switch on Shimano's rear derailleurs with a clutch.

The SRAM NX Horizon clutch is always locked on. It can not be locked off. It has what SRAM call it's type 3 clutch. You can find out online why SRAM say they moved to the type 3 clutch and conjecture as to why they had to. If it works then great and who should care why. SRAM is a great company. I have had lots of their products from complete SRAM MTB drivetrains to dropper posts and suspension forks.

Like all products the SRAM NX Horizon rear derailleur has a mean time before failure and it needs fitting and servicing to their guidance. SRAM also has a compatibility matrix for its use, as this is what they have designed and tested it for.

If an individual builds up a bike from components or swaps in and out certain components then they take on additional risk and responsibility if they don't follow the component manufacturers usage and compatibility guides. But if you buy a complete bike then the company who sold you the bike takes on this responsibility and risk. If you buy from a shop then they have a contract that I'd assume passed on that risk and responsibility onto the company that sold it to them, which is often a distributor. Ultimately the bike manufacturer takes on the risk and responsibility. Although it's common these days to buy direct from the bike manufacturer, they sometimes have an arrangement with local bike shops (LBS) to provide a service to act on their behalf. How that works contractual is between them but your contract is with who you bought the bike from. Or put another way the LBS could simply be providing a service on behalf of the bike manufacturer. Well at least in the UK.

It's really common to mix and match components as broadly bikes have explicit or implicit standards and components are generally interchangable. It's nothing to be afraid of, but the bike designer takes on additional risk when doing so with a sub system of a bike. For example choosing components from different manufacturers to complete the drive train. Particularly the rear derailleur and front chainring. SRAM in particular say it's really important to match with their rear cassette and chain. Whereas in my view and experience using a different braking system to that included in the associated groupset carries much less risk. It is a separate sub system.

But in the end there are many reasons why chains come off the front chainring. Often due to worn out parts, poor maintenance or an inexperienced rider. Regardless chain drops occur to the best of us. When they do it should happen in a controlled way so that the chain doesn't get trapped and potentially cause the chain to break or other bike components to get damaged. Or worse, rider injury!

I'm surprised at the tone of some of the posts and replies. They don't reflect the humility or reality of my previous paragraph. But that's life folks!

Look after yourselves.
 
First of all, I wanted to say "Hello" to you, as I can see you mostly on Strava, zooming your Vado almost everyday!

Secondly, you are the OP there, and you initially had issues with chain dropping on your Vado. How can you see it in the perspective of several months of your Vado riding?

Thirdly, a gentleman here claims he cannot lock the derailleur cage on his SRAM Horizon NX derailleur. I was wondering what was that button for?
View attachment 150599


Oh you! :)
My most recent chain I replaced at 2200 mi. or so (I'd need to be sure that was the mileage I had when I changed i) I used a KMC chain. I use HotWax
( https://www.amazon.com/gp/product/B00KXQS6YI/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 ) and try clean it (the chain) every week or 2 and have had no drop offs in some time. I'm approaching 4,000 miles on the June 2022 acquired Vado 5.0 and maybe 2 or 3 chains, 1 new cassette (I've ultrasonic cleaned them too at times). However, I cannot say it is from a KMC chain or the Sram chains that I also used in the past (dropping). It might even be me with my consistent use of the shifter up and down as I accelerate and de-accelerate attempting to keep my cadence uniform. There may even be a few missed shifts that created the drops. We will see.
I normally remove the chain around 200-500 miles and do a new Hot Wax bath after using the Ultrasonic cleaner with Simple Green, but when to lazy a quick wipe down of the chain and I at times use the spray wax in the can....and it's pretty good. ( https://www.amazon.com/gp/product/B0012TZ1RU/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 )
As a side note, I see that the Tero X has some sort of chain drop "inhibitor" of sorts and no chain guard. Did Specialized make this piece to keep the chain on?
 

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As a side note, I see that the Tero X has some sort of chain drop "inhibitor" of sorts and no chain guard. Did Specialized make this piece to keep the chain on?
It is so called "chain guide" and is a norm on e-MTBs. The point is, you ride an MTB in really rough terrain and sometimes do low jumps. Better the chain does not drop on a technical singletrack ride!

Chain should never drop even if other types of e-bikes are ridden on light trails. The only case I had chain drops was the derailleur dramatically out of adjustment.
1680317948777.png

A type of trail I recently rode on Vado SL.
 
It is so called "chain guide" and is a norm on e-MTBs. The point is, you ride an MTB in really rough terrain and sometimes do low jumps. Better the chain does not drop on a technical singletrack ride!

Chain should never drop even if other types of e-bikes are ridden on light trails. The only case I had chain drops was the derailleur dramatically out of adjustment.
View attachment 150701
A type of trail I recently rode on Vado SL.
Lovely Photos. I'm impressed that your bike handles this terrain well. I'd use my cross country MTB but I'm super cautious.

Would Specialized view this terrain as being appropriate for the Vado SL? I am not sure of their opinion. It seems OK, their sales & marketing for the bike matches what I see in your photos but perhaps the gradients are too steep or there are too many exposed tree roots to dodge? Specialized have buried the intended use of the Vado SL in Appendix A of the owners manual. It says the Vado SL is designed for Condition 2. Bikes designed for condition 1, plus smooth gravel roads and improved trails with moderate grades where the tires do not lose ground contact. The intended use is paved roads, gravel, or dirt roads that are in good condition and bike paths.

My chain drop happened on the Trans Pennine Way in the North of England, which is designed and maintained to more than meet Specialised Condition 2 intended use. But chain drops happen, that's not my concern other than it should be minimised due to inconvenience. What is my concern is that the version of Vado SL I received traps the chain between the frame and the chainring. The chain can not be removed without unbolting the chain ring from its spider. This is more than a minor inconvenience, It's a major inconvenience and potentially very dangerous for the rider when it happens. Perhaps my original reply should have made this issue clearer.
 
I experienced another chain drop with a relatively new chain; ironically in the same place I dropped chain a few times before. Here's the scoop:
  • Chain, as mentioned, is quite new, has ~300mi on it. SRAM 9-speed chain.
  • I had recently done a deep clean and lube.
  • Derailleur is adjusted perfectly, snicks through gears effortlessly and no noise.
  • I was going downhill too fast and not pedaling. The trail has numerous minor erosion washouts (2-3" deep, 4-6" across).
IMHO the combo of the washouts + speed + not pedaling resulted in me having to reseat my chain at the bottom of the hill.

I suspect after I put another 2k miles on Vado, I'll learn. Maybe.
 
Spitballing here, but it might be worth comparing number of links in your chain to others, just to rule out the possibility of an extra couple links.
 
Spitballing here, but it might be worth comparing number of links in your chain to others, just to rule out the possibility of an extra couple links.
I remember a while ago, last year on the other Vado, I had counted links, taken pictures, was it 124, 126, 128, not remembering the exact #, but does anybody have the knowledge as to the exact number of links per chain, per bike, per drivetrain? Does the LBS, manufacturer, anyone know the specifications so that it can be be verified and validated, once and for all?
 
I remember a while ago, last year on the other Vado, I had counted links, taken pictures, was it 124, 126, 128, not remembering the exact #, but does anybody have the knowledge as to the exact number of links per chain, per bike, per drivetrain? Does the LBS, manufacturer, anyone know the specifications so that it can be be verified and validated, once and for all?
SRAM and Shimano chains typically come with no more than 126 links, so it's unlikely a Specialized requires more.
 
SRAM and Shimano chains typically come with no more than 126 links, so it's unlikely a Specialized requires more.
Shimano e-bike chain (CN-E8000) comes with as many as 138 links... :D KMC has one, too.
I remember a while ago, last year on the other Vado, I had counted links, taken pictures, was it 124, 126, 128, not remembering the exact #, but does anybody have the knowledge as to the exact number of links per chain, per bike, per drivetrain? Does the LBS, manufacturer, anyone know the specifications so that it can be be verified and validated, once and for all?
The proper chain length depends on:
  • The chain-stay length
  • The number of teeth on the chainring
  • The number of teeth on the largest sprocket
  • The short or long derailleur cage
  • Dedicated 1x drivetrain or another system
For example, my Vado 6.0 ST (customized) size M is:
  • Chain-stay length: 478 mm
  • A 42T chainring
  • 46 teeth on the granny gear sprocket of the cassette
  • Long cage derailleur
  • Dedicated 1x drivetrain: Yes
There are many "Bike Chain Length Calculators" on the Web. These, however, are either limited or do not take some parameters into the account, so I cannot recommend any. Any bike chain length calculator I found was suggesting a 120 link chain for my e-bike. The reality is, my Vado 6.0 requires precisely a 126 link chain.

One of the most detailed articles on the chain length has been published by Park Tool:

The practical indication: If your chain is sized correctly on your 1x drivetrain, the derailleur cage should be in the 5 o'clock position when the drivetrain is in the "granny gear". With such a setup, the derailleur cage points at 7-8 o'clock position in the top gear.

Now, the funny part: When I first got my original Vado 5.0 with the 48T chainring, the chain size was 132 links. Wrong. It should have been either 128 links for good tension of the chain or 130 links for a weaker but acceptable fit. 132 links made the derailleur cage be totally horizontal (9 o'clock position) which was unacceptable and could have led to chain dropping!

For your information: My Vado SL 4.0 EQ size M originally required 120 chain links for a 44T chainring and 42T largest cassette cog. After I have replaced the cassette to 11-36T, the proper chain length turned out to be 116 links which enables me to easily find inexpensive replacement chains.
 
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Shimano e-bike chain (CN-E8000) comes with as many as 138 links... :D KMC has one, too.

The proper chain length depends on:
  • The chain-stay length
  • The number of teeth on the chainring
  • The number of teeth on the largest sprocket
  • The short or long derailleur cage
  • Dedicated 1x drivetrain or another system
For example, my Vado 6.0 ST (customized) size M is:
  • Chain-stay length: 478 mm
  • A 42T chainring
  • 46 teeth on the granny gear sprocket of the cassette
  • Long cage derailleur
  • Dedicated 1x drivetrain: Yes
There are many "Bike Chain Length Calculators" on the Web. These, however, are either limited or do not take some parameters into the account, so I cannot recommend any. Any bike chain length calculator I found was suggesting a 120 link chain for my e-bike. The reality is, my Vado 6.0 requires precisely a 126 link chain.

One of the most detailed articles on the chain length has been published by Park Tool:

The practical indication: If your chain is sized correctly on your 1x drivetrain, the derailleur cage should be in the 5 o'clock position when the drivetrain is in the "granny gear". With such a setup, the derailleur cage points at 7-8 o'clock position in the top gear.

Now, the funny part: When I first got my original Vado 5.0 with the 48T chainring, the chain size was 132 links. Wrong. It should have been either 128 links for good tension of the chain or 130 links for a weaker but acceptable fit. 132 links made the derailleur cage be totally horizontal (9 o'clock position) which was unacceptable and could have led to chain dropping!

For your information: My Vado SL 4.0 EQ size M originally required 120 chain links for a 44T chainring and 42T largest cassette cog. After I have replaced the cassette to 11-36T, the proper chain length turned out to be 116 links which enables me to easily find inexpensive replacement chains.
I guess that I just have to make sure that I swap out the chain (when needed) BEFORE I have my Tequila :)
 
Normal? Dunno, not an expert, but I can take photos if needed. I have my old, original chain, I will ask my wife to help me count links tonight. ;)
I wrote about the proper cage positions earlier in this thread.
How do you know Specialized has not shortened the stock chain in the production bike?
 
Just a reminder that each link in a bicycle chain is ½" long, so if you remove the chain you can just measure to count links (modulo stretch). But, even on the bike you can mark a pin and measure along the top straight section, mark the end pin, rotate the cranks, measure, etc.
 
PLEASE, WHY is it that WE as the owners of a bike need to have specific knowledge of specifications that are not 100% verified? It makes my life miserable.
 
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