Chain Life

steve_sordy

Wedding Crasher
Nov 5, 2018
9,033
9,481
Lincolnshire, UK
Just catching up on this. People bang on about torque and power, but it is the tension in the chain that does the damage. Torque = force x radius, where in this case, force = chain tension. The radius on the rear changes with each gear, but the tension in the chain is constant as it is applied by the rider on a fixed radius front ring. Well.... not constant really because it pulses as the rider pedals.

To minimise the tension in the chain, the rider should use larger gears at the back. Therefore a higher cadence. The next thing to do is to reduce the peak tension in the chain by levelling out the pulses from the rider. I expect that elliptical chain rings properly installed will extend chain and gear life.

Edit: When I wrote the bit about elliptical chain rings I was still thinking in clockwork bike mode. I accept that they won't work on an eBike. :giggle:
 
Last edited:

Mcharza

E*POWAH BOSS
Aug 10, 2018
2,617
5,393
Helsinki, Finland
You were thinking too scientifically. Isn't it quite clear eMTB vs normal bike.
Too small a cadence, which causes great pulling power to the chain. The engine brings more power than what your own thighs could produce.
 

DONUT

New Member
Feb 18, 2019
16
8
Hampshire
SRAM XX1 chain - new on bike Dec 18 (19 levo). Replaced yesterday at a little over .75 - 392 miles. Sounds terrible compared to an acoustic bike but I used to ride around 12 miles on an average ride on my old turner, now my rides are more like 35 miles every time. 3 times the miles means the chain is going to wear out 3 times quicker and thats before you get into all the other factors that the engineers and scientists above are suggesting ebikes introduce. So is it that bad?
 

jxj

Member
Jun 28, 2018
83
68
Sierra California
Steve sordy, eccentric chainrings are not compatible with the Specialized/Brose motored bikes that I have ridden. The chainring free wheels relative to the crankset so eccentric indexing is variable and therefore will not provide the expected result.
 

nicklej

Active member
Patreon
Oct 11, 2018
156
122
Camberley
I wondering about the same.
Can I use, without problems..., a 114 link PC1110 on my Levo 2019, size Large, with 32t chainring and 11-42?
Original is 116 links...
I wondering about the same.
Can I use, without problems..., a 114 link PC1110 on my Levo 2019, size Large, with 32t chainring and 11-42?
Original is 116 links...
Hi mate, I run a 34t chainring with the 42t largest rear sprocket. 114 links works for me on my 2018 levo.
 

steve_sordy

Wedding Crasher
Nov 5, 2018
9,033
9,481
Lincolnshire, UK
Steve sordy, eccentric chainrings are not compatible with the Specialized/Brose motored bikes that I have ridden. The chainring free wheels relative to the crankset so eccentric indexing is variable and therefore will not provide the expected result.
OK, very fair comment. My experience of that bike is limited to a test ride. Every day is a learning day. I'm obviously still thinking in clockwork bike mode.

Is the chainring freewheeling relative to the crankset a Speccy/Bros thing or is that true in general of all bikes? ...............Actually, hold that thought, my bike is too! (Focus Jam2/ Shimano). So it looks like that may be a general emtb thing?
 

jxj

Member
Jun 28, 2018
83
68
Sierra California
OK, very fair comment. My experience of that bike is limited to a test ride. Every day is a learning day. I'm obviously still thinking in clockwork bike mode.

Is the chainring freewheeling relative to the crankset a Speccy/Bros thing or is that true in general of all bikes? ...............Actually, hold that thought, my bike is too! (Focus Jam2/ Shimano). So it looks like that may be a general emtb thing?
I'm not sure if it is every bike but many that I have ridden are. All of the Brose bikes Bulls and Specialized are that way. I'm learning too.
 

Maastricht

E*POWAH Master
Oct 3, 2018
646
655
M
Hi guys,

I owe you an update on the issue I described earlier on in this thread...

So the issue was extreme wear on my 2019 Levo Comp KMC X11ET chain. After only 300km the chain was stretched beyond 0,75% and due to this the SRAM PG-1130 cassette was so worn out that a new chain slipped over the cassette teeth.

In the meantime I have been in contact with KMC and my LBS. The result is that KMC told me that I actually seem to have a e11. I thought it was the X11ET as this was mentioned on the Specialized website. The X11E chain (the "T" was just an internal KMC indicator and therefore no one is able to find it on a datasheet) was replaced by the improved e11. The e11 should have a better tensile strength and improved riveting connection compared to the X11E.

KMC also told me that strechting the improved e11 chain in only 300km. (even when mostly driving in eco) is way too fast. Therefore they wanted me to return the chain for further examination. I told them that I am happy to send the chain (and they would send me a new chain in return free of charge) but then I wouldn't be able to drive my bike anymore as the new chain slips over the cassette. The end result is that my LBS jumped in. They replaced both the chain and cassette under warranty. I assume they will solve the issue with KMC as they will send my old chain to KMC.

During the exchange they also discovered that the bearing was completely corroded of one of the SRAM GX derailleur jockey wheels. They also changed this wheel. All that happened in only 300km which makes me doubt the quality of the SRAM bearing seals as well.

Anyway, all is good now so I am happy again and just wanted to thank you all once more for your contributions!
 

Thomas

Well-known member
Aug 29, 2018
248
255
Europe
Kodos to Specialized and also KMC.
Some corporation should learn how it is done right by a customer.
Got ride of Sram from a get go, fitted Shimano and never look back.
 

Thomas

Well-known member
Aug 29, 2018
248
255
Europe
Why? It looks like the LBS were the good guys here, not the almighty Spesh.
Do you think that LBS pay out of there own pocket for new chain and cassette? :ROFLMAO:
Everything is approved from specialized. I got some components that are not Specialized related replace under warranty over the years and guess what, everything was approved by Specialized.(y)
 

Maastricht

E*POWAH Master
Oct 3, 2018
646
655
M
Why? It looks like the LBS were the good guys here, not the almighty Spesh.

Also Specialized contributed here via PM. However I contacted KMC already too. So in the end the issues are solved and will rotate 2nd chain now much more quickly.
 

jxj

Member
Jun 28, 2018
83
68
Sierra California
Update on my Sram PC-1110 test. It is noisy and hard shifting. Especially slow coming down cassette to smaller cogs it holds forever. Also so marginal on the 114 link with my 36T front. I'm going to try a KMC 93 next. Abandoning the PC-1110. Only going to run 116 links. Hope to convert to all shimano drive in the future.
 

hokkane4

Member
Jan 3, 2019
52
27
Finland
Also so marginal on the 114 link
Did you adjust derailleur tension when you tried different length chain? At least with SRAM cassette just 2 links difference in chain length with unadjusted derailleur made shifting very bad.
 

jxj

Member
Jun 28, 2018
83
68
Sierra California
Yes adjusted angle and b tension. Angle of rear mech is far forward in low gear even after adjusting. Looking at the link design close it doesn't appear as sophisticated as the kmc chains. Perhaps 114 is just too short for the 36T front
 

khorn

E*POWAH Elite World Champion
Patreon
Jul 19, 2018
980
1,055
Denmark
Yes adjusted angle and b tension. Angle of rear mech is far forward in low gear even after adjusting. Looking at the link design close it doesn't appear as sophisticated as the kmc chains. Perhaps 114 is just too short for the 36T front[/QUOTE

If you have a 2018 Levo the stock link numbers are 116 so if you have only 114 links together with 4 more teeth's in the front, then I would say that your chain is critically short and that could have influence on shifting as well as life span.

Karsten
 

Jimi

New Member
Jul 18, 2018
19
16
Land of ice and cold...
2018 Turbo Levo with about 1200km and chain ~0.75 (from Specialzed www saying chain is KMC X11ET). I have been very lazy, poorly lubricated and cleaned. Seems to be ok km considering above facts.

What would be recommended for the replacement? e11? Another brand?
 

Akiwi

🐸 Kermit Elite 🐸
Feb 6, 2019
986
1,292
Olching, Germany
I got about 2000 in on my first once chain, and I have done 1500 km on the second chain no problems there. I weigh about 85kg. Most rides are trails, and a lot of vertical metres. Normally uphills are paved or fire roads. However I ride on flat often with the motor off, and tend to venture into modes above eco only when the going gets tough. Really steep rough etc. It helps keep me fit, and enables a lot longer rides. My biggest ride was 2200m vertical and 70km. Battery wasn't empty. So my advice is to use your legs more.
 

jxj

Member
Jun 28, 2018
83
68
Sierra California
Jimi,
I too have the 2018 Levo. I got close to 900 miles on my first chain when it was just hitting 0.5% on some of the links. I tried the Sram PC-1110 due to low cost at $15 in the US and while others had good success it did not downshift well for me at all and no adjusting could fix it for me. I'm just mounted a KMC X11.93 and will be trying it. Some swear by the KMC OEM 11e chain models and others have had issues with broken links. I'm hoping that we can all share our experiences here to give hints on what works and doesn't

There are many threads on this site and others that discuss chains and life. My largest takeaway is that results seem to vary greatly depending on maintenance, rider style, weight, weather and soil conditions.

Testing of various chains for breaking strength was performed here 12 years ago:
http://www.cantitoeroad.com/assets/...permann/Connex_Breaking_Load_Test_Results.pdf
This is an old test and doesn't cover any KMC chains, however, my one takeaway is that the variation on breaking strength is not a huge span so you likely can experiment with various brands.

The breaking strength on the test linked here runs around 10,000N. My calculations show that at 1000W power if you keep your cadence at 80 you are likely putting about 2,000N on the chain. Roughly 20%-25% of the breaking strength of a typical chain. Of course the ability to break things goes wild when shifting under load.
 

madcow

New Member
Jan 28, 2019
18
15
DE
Nice thread. I'm riding a Levo FSR 2018 and it looks like my KMC OEM chain is also at 0,75% now. Time to give SRAM PC X1 a shot.
After reading the entire thread, a few questions popped up for me:

1) All are reporting for the levo 116 links, mine has 118?! Is it due to I have size XL?
2) Nooby question: When measuring the tension, do I have to put the chain under tension with the pedal? If I do, then my chain has reached 0,75%, otherwise tool says it is fine.
3) When I'm replacing the chain, does it make sense to keep the old chain for later use when the cassette has worn a little bit more of?
 

madcow

New Member
Jan 28, 2019
18
15
DE
Little update here.
1) solved. Misscount from my site. Mine has also 116 links.
2) Still not sure. I tend to say no extra tension.
3) I will keep the old chain. Will see for what it is good for...

Change to PcX1 was easy, but I think it is a bit more noisy than the old one...
 

Apples

Well-known member
Oct 27, 2018
134
127
Wiltshire
So popped into the LBS today and had a chat , owned bike for 6 months , chain stretch measured at just about 1 , 500 miles total , say 450 of which is quite hard off road , muddy riding , cleaned and lubed each time , 50 miles on road between work and stuff , I’m 18 stone riding a 2019 Carbon levo

Bike shop recommended leave it , if it starts slipping then change , but aim is to get to 12 months then change cassette and chain !

Sounds like a good plan about 100 quid for a years riding ... thoughts ??
 

Paul Mac

E*POWAH Elite World Champion
Patreon
Subscriber
Jul 9, 2018
997
1,046
Uk
So popped into the LBS today and had a chat , owned bike for 6 months , chain stretch measured at just about 1 , 500 miles total , say 450 of which is quite hard off road , muddy riding , cleaned and lubed each time , 50 miles on road between work and stuff , I’m 18 stone riding a 2019 Carbon levo

Bike shop recommended leave it , if it starts slipping then change , but aim is to get to 12 months then change cassette and chain !

Sounds like a good plan about 100 quid for a years riding ... thoughts ??
That's exactly what I am doing.
Chain was shown over 0.75 stretch over 500 miles ago and still going strong on same cassette.
 

Swissrider

Well-known member
Nov 1, 2018
368
384
Switzerland
I have two ebikes, a KTM hybrid and a Kenevo. Both chains show the same amount of wear - just into the red on my 1st generation Park tool which corresponds to 0.75% (checked by ruler method) wear. I’ve done over 900k on the Kenevo but 2600k on the KTM! I don’t ride the KTM off-road and seldom even in the rain. I just lube the chain (with fork oil as it happens) from time to time. The Kenevo is also ridden in ideal conditions, never muddy and seldom dusty. Also more than half of the distance will not be pedalling as it will be downhill and I use occasional uplift. A properly lubed chain in good conditions will last a very long time - consider a cam chain in an engine, which can last the lifetime of an engine. If chains on a motorbike were covered and ran in an oil bath, they would probably last the life of the bike but aesthetically everyone wants to see the chain! My point is that the conditions that one rides in has a huge impact on chain life.
 

jxj

Member
Jun 28, 2018
83
68
Sierra California
Update to add to our community experience. I ran the OEM chain for about 1000 miles and it is just over 0.5% wear. I cleaned and lubed it and put it in a plastic bag and now carry it as a spare as I am frequently far from civilization. I put the KMC X11.93 at 118 links on and have about 150 miles on this chain. It shifts and acts the same as the OEM chain and in the USA can be had for about $25 from places like Amazon. I've had it out on climbs with a combined legs and motor power up to 1100W on climbs and no issues. Smooth shifting.
 

mccltd

New Member
Apr 5, 2019
39
11
kent
So after reading this interesting thread is there a recommendation for a chain for a 2019 levo Comp?
I want to get a spare to carry around.
Maybe a Poll required.
 

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

556K
Messages
28,097
Members
Join Our Community

Latest articles


Top