Chain ring advice please

kla456

Member
Mar 8, 2020
84
19
Scotland
I have just under 2000 miles on my bike and I’m not sure if my chain ring is in need of changing, I have looked at pictures of brand new ones and I can’t see any difference really, I clean my transmission every time I come back from a ride and I clean and lube the chain meticulously too, I don’t know how I’ve done it but my cassette is still the original from new but I’m going to change it as it’s showing slight signs of wear, anyway I have taken a picture of my chain ring to see what you all think, oh another thing, I’m having trouble locating a Sram chain ring for my Whyte e-150rs, anyone know something I don’t please

View attachment 52646
Just wondering if the bike was bought last year during the period of Covid?
I had a chainring problem last year. I took the number stamped on the chainring and wrote to the part manufacturer. Turns out they don't make a chainring for SH12! I wrote to the bike seller and they wrote to the manufacturer. Bike manufacturer replied with an apology explaining about supply issues during the lockdown. They mailed me the correct part and paid for LBS to do the work.
I don't blame the bike manufacturer who has to keep working and they owned up when presented with firm evidence. No names, no pack drill.
 

EMTBSEAN

E*POWAH Elite
Subscriber
Feb 20, 2020
1,038
733
Sheffield
Just wondering if the bike was bought last year during the period of Covid?
I had a chainring problem last year. I took the number stamped on the chainring and wrote to the part manufacturer. Turns out they don't make a chainring for SH12! I wrote to the bike seller and they wrote to the manufacturer. Bike manufacturer replied with an apology explaining about supply issues during the lockdown. They mailed me the correct part and paid for LBS to do the work.
I don't blame the bike manufacturer who has to keep working and they owned up when presented with firm evidence. No names, no pack drill.


Yeah I bought my bike in the first week of March 2020, the thing is my chain ring still works without any issues that I see of anyway, I have been in touch with Uber bike about a spider and a chain ring for my bike so I think I’m gonna go down that route but thanks for letting me know about the route you went down mate
 

onionfx

Member
Mar 12, 2021
2
0
Kilkeel
This thread could turn into "rate my ring".
I haven't seen a pic of this type anywhere yet.
After exactly 492km this chainring (with up to 85Nm of torque) wrapped the chain around the crank axle 1.25 times (the chain does go past the chainstay when the suspension is compressed).

The new chain it does seem be "hanging on" to the chain a bit.
With it being alloy is this the sort of lifespan you'd expect?
The chain is less than 0.5% on the chain checker (it's the best looked after chain I've ever had :cool:)
(It's "Whyte" branded and it has that special "E" as well)

I think I'm going to try to get a steel one...

2021-03-12 17.15.22.jpg


2021-03-12 17.15.32.jpg
 
Last edited:

Rik08

Member
Jan 9, 2021
68
22
Leamington
2021 E150RS - any ideas what this chain set is ? Different to the SRAM ones shown above - can’t find one like this online - Whyte spec sheet says Sync2, direct mount, 34T for Bosch Gen 4 ! Has Whyte emblem on it ?

17433E52-05EE-420E-9A0E-23C933EF67B8.jpeg
 

Rik08

Member
Jan 9, 2021
68
22
Leamington
This thread could turn into "rate my ring".
I haven't seen a pic of this type anywhere yet.
After exactly 492km this chainring (with up to 85Nm of torque) wrapped the chain around the crank axle 1.25 times (the chain does go past the chainstay when the suspension is compressed).

The new chain it does seem be "hanging on" to the chain a bit.
With it being alloy is this the sort of lifespan you'd expect?
The chain is less than 0.5% on the chain checker (it's the best looked after chain I've ever had :cool:)
(It's "Whyte" branded and it has that special "E" as well)

I think I'm going to try to get a steel one...

View attachment 55506

View attachment 55507
Just noticed this pic after I’d posted mine !! Any joy with a replacement? Mines same as yours !! Can’t seem to find a replacement like for like
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,570
5,063
Weymouth
With " Whyte" etched on it the chainring is probably a batch specifically made for Whyte but I would have thought any 3mm offset chainring designed for Bosch Gen 4 would do........preferably steel for better wear.
( not sure on this point but I believe the Bosch Gen4 axle is ISIS standard size so as long as the chainring is ISIS I do not see anything else that makes a chainring specific to Bosh Gen 4 fitting?............happy to be corrected if that is wrong!)

If the chainring was supplied by SRAM the serial number should be etched on the back.
SRAM serial number for Bosch Specific SRAM XSYNC 2 is.............. CR-XSYNC-BOS-B1
 

onionfx

Member
Mar 12, 2021
2
0
Kilkeel
I scoured Europe and eventually found a 'standard' steel 34 tooth and put that on.
Didn't fancy replacing it every 4 months - my riding buddy has a Cube with standard ring and has over 1000kms with no problems - as far as I can tell (failing the magnet test) the Whyte marked one is alloy.
The chain line was pretty much the same - maybe 0.5 - 1mm different (but my measurements weren't super accurate either).

I've done about 250km on it since and no problems.

This was the one i got from Italy

Ended up buying a spare from France (xxcycles)

Also JINX on the photos!!!
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,570
5,063
Weymouth
Typical Whyte - no email response, I’m not desperate so will contact them when it needs replacement!
The one is the post above is the right one and is a SRAM component (steel). Just makes sure the one you order is boost ( 3mm offset).
 

Gasser

Member
Feb 6, 2019
39
18
Sidmouth Devon
thanks for pointing that out to me mate, I didn’t give that a second thought, if my chain was old and stretched out I might have bought a 36t chain ring and a new chain at the same time but my chain is only around 300 miles so I’m gonna keep it stock with the original 34t chain ring, thanks ?
Just curious, if you have got 2000mile out of the cassette what is your chain maintenance regime (especially in muddy grimy conditions) and when do you change them, mileage or wear tool? Cheers
 

EMTBSEAN

E*POWAH Elite
Subscriber
Feb 20, 2020
1,038
733
Sheffield
I change my chain long before it’s ready and I clean my transmission every time I get back from a ride, in fact I’ve just fitted a Sram XO1 chain and fitted a new inner shifter cable too, my bike changes gear with no issues and the chain ring seems fine
 

Tribey

Active member
Jan 1, 2019
313
225
South Devon, UK
@Beezerk What @raymal has done with his front ring (36t instead of a 34t) is less than a 6% difference. An average gap between cassette gears is 15%. So as he says, a minimal change.

Many riders have been fitting shorter crank arms which also changes the overall gearing, all without any bad effects from the motor. Going from 170mm to 160mm for example has exactly the same effect on overall gear ratio as fitting a 36t instead of a 34t. They both make achieving the same speed 5.88% harder, although I believe that it may feel quite different.

Just reading through the thread to get hints on new chainring purchase, but I cannot understand your point on how changing the crank arm length will affect the gearing in any way.
 

Jackware

Fat-tyred Freakazoid
Subscriber
Oct 30, 2018
2,087
2,301
Lancashire
Just reading through the thread to get hints on new chainring purchase, but I cannot understand your point on how changing the crank arm length will affect the gearing in any way.
I think Steve meant the change in your cadence for a given speed by reducing the chainring or crank length.
 

Tribey

Active member
Jan 1, 2019
313
225
South Devon, UK
I think Steve meant the change in your cadence for a given speed by reducing the chainring or crank length.

No, cadence and speed are directly linked to the gearing, not the crank length, the chain ring size will definitely make a difference though.
I see the 2021 models kept the same 34 tooth chain ring, so will I.
 

steve_sordy

Wedding Crasher
Nov 5, 2018
9,021
9,462
Lincolnshire, UK
Just reading through the thread to get hints on new chainring purchase, but I cannot understand your point on how changing the crank arm length will affect the gearing in any way.
It does not affect the actual gears on the bike, but the cranks are part of the overall gearing of the bike. You apply a force to a long crank and you get a big torque. The same force applied to a short crank reduces the torque. So to get the same power input you have to pedal faster. Doesn't that sound like gearing to you? When cranks are shortened they tend to move in 5mm steps 175, 170, 165... These are tiny steps (175 to 170 is less than 3%) whereas an average gear shift is 15%, so crank changes tend to get missed. But it is real, as is the wheel size issue. Moving from a 27.5" wheel diameter to a 29" diameter makes it harder by just over 5%. But the easier rolling capacity of the bigger wheel helps to obscure the extra torque required to turn the wheel.

If you are still doubtful, think it through by making changes to the bike (on paper) and see what happens from one turn of the cranks. Then start changing crank length, wheel size, shift a few gears.

Cranks, gears, wheels...it's all gearing. :)
 

Penttithefinn

Member
Feb 3, 2021
79
87
Suffolk
It does not affect the actual gears on the bike, but the cranks are part of the overall gearing of the bike. You apply a force to a long crank and you get a big torque. The same force applied to a short crank reduces the torque. So to get the same power input you have to pedal faster. Doesn't that sound like gearing to you? When cranks are shortened they tend to move in 5mm steps 175, 170, 165... These are tiny steps (175 to 170 is less than 3%) whereas an average gear shift is 15%, so crank changes tend to get missed. But it is real, as is the wheel size issue. Moving from a 27.5" wheel diameter to a 29" diameter makes it harder by just over 5%. But the easier rolling capacity of the bigger wheel helps to obscure the extra torque required to turn the wheel.

If you are still doubtful, think it through by making changes to the bike (on paper) and see what happens from one turn of the cranks. Then start changing crank length, wheel size, shift a few gears.

Cranks, gears, wheels...it's all gearing. :)
I have put this up before but it works
!Sheldon Brown's Bicycle Gear Calculator
 

Penttithefinn

Member
Feb 3, 2021
79
87
Suffolk
Well, I tried the Browns calculator, I changed the crank length details, but the resulting gearing figures remained the same!
As steve_sordy said crank length effects torque required, so yes from a static point of view it doesn't make sense. Just use the bits that suit your requirements, or make your own Excel spreadsheet.
 

Giff

Active member
Subscriber
Oct 14, 2019
459
127
Cheshire UK
On the subject of wear. My cassette, chain and chain ring have done about 2500km. The chain has been worn past 1.0 for the last 1000km or so. All gears seem ok with an occasional ghost change. Am I risking chain breakage or other failure if I keep using it ?
I have a new cassette, chain and chainring ready but would the advice be to change them now or wait?
 

Rik08

Member
Jan 9, 2021
68
22
Leamington
Good effort ! They recommend changing the chain at 0.5% on an ebike ! They say 1.0% is the maximum! But if it’s still working stick with it as all parts will be wearing out and then replace when shifting / slipping gets too much, I’d carry a spare link with me just in case chain snaps so you can get home !
 

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