SRAM's new 2023 Drivetrain allows full power shifts

Dave_B

E*POWAH Elite World Champion
Subscriber
Aug 29, 2020
1,420
1,536
Newquay
yes it does, plenty of clearance with the existing chain guide (which I would like to remove because it serves no purpose as far as I can see other than trap mud and grass.
 

Alexbn921

Well-known member
Sep 27, 2021
545
506
East Bay CA
I got to ride the new Sram T last night and the shifting was excellent. Significantly better than the old AXS and I would rate it above Shimano too. Shifts are very smooth and since there is no feedback from a cable, you don't feel anything. Overall it's the best shifting Sram has ever made.

If I could change it out would I? No. It's within a couple percent of Shimano HG+ and for wear items, I not want to spend bank on the chain and cassette. if you where doing a new build it's better than AXS, but not worth the price over Shimano.

Also as a side note, last night a stick stuck in a buddies Sram 11 speed, pushed the derailleur into the spokes and ripped it off the hanger breaking his wheel. Frame is 100% fine and even the derailleur can be reused with a new hanger. Not sure of the damage that would have happened with Sram T.

If you hear a bad shift or something in your drivetrain, stop pedaling and lock up the rear wheel. Never try to power through.
 

Alexbn921

Well-known member
Sep 27, 2021
545
506
East Bay CA
1681444938942.png
 

Alexbn921

Well-known member
Sep 27, 2021
545
506
East Bay CA
Slipped off a 1 foot high log on a creak crossing at 5 mph.
Ordered spare parts with the kit. Should be back up and running today. We will see how it shifts.
 

pontoon

New Member
Apr 24, 2023
61
20
USA
I’m trying to figure out chain line. I ordered 00.7918.280.002 for my 23 levo (

SRAM XX Eagle T-Type Ebike AXS Groupset - 104BCD 36T, Derailleur, Shifter, 10-52t Cassette, Clip-On Guard, Arms not)​


If I get the Sram Brose direct mount chainring (CR-XX-BR-D1), will that give a 55mm chainline, or would it require milling?

Are there any other chainrings that will work? I can mill something if needed. CR-XX-BR-D1 is not in stock in the US afaict anyway
 

Rich-H

Member
Apr 3, 2023
148
108
Hampshire
I’m trying to figure out chain line. I ordered 00.7918.280.002 for my 23 levo (

SRAM XX Eagle T-Type Ebike AXS Groupset - 104BCD 36T, Derailleur, Shifter, 10-52t Cassette, Clip-On Guard, Arms not)​


If I get the Sram Brose direct mount chainring (CR-XX-BR-D1), will that give a 55mm chainline, or would it require milling?

Are there any other chainrings that will work? I can mill something if needed. CR-XX-BR-D1 is not in stock in the US afaict anyway
I'm really not sure why people are modifying the DM chainring. When I removed the original spider and chainring and compared it to the DM chainring, there was around a 3mm difference. This makes sense as the original spider gives a 52mm chain line and the DM should give you a 55mm chain line.

I've been running the DM chainring (unmodified) for a while now without any issues...
 

blob

New Member
Feb 22, 2023
23
7
Croatia
I’ve installed the Brose kit on my Turbo Levo (including the direct mount chainring with the incorrect offset) and can’t really get it to work perfectly. Gear 3 is the most problematic one, it keeps jumping to other gears under higher load and I can’t micro-tune it to work well. And gear 9 seems a bit noisier compared to others. The rest work fine.

Could these problems be caused by the chainring offset?
 

Rich-H

Member
Apr 3, 2023
148
108
Hampshire
I’ve installed the Brose kit on my Turbo Levo (including the direct mount chainring with the incorrect offset) and can’t really get it to work perfectly. Gear 3 is the most problematic one, it keeps jumping to other gears under higher load and I can’t micro-tune it to work well. And gear 9 seems a bit noisier compared to others. The rest work fine.

Could these problems be caused by the chainring offset?
As per my previous post, I've been running the DM chainring for around a month now without any issues. Have you measured the chain line? Even if the chain line was out by a couple of mm I wouldn't expect to have the issues you are describing.

SRAM tech support are pretty good, might be worth getting in contact with them...
 

pontoon

New Member
Apr 24, 2023
61
20
USA
I talked to SRAM tech support about the topic. They were super helpful.

I was asking if the 52mm chain line is alright, or if I need to find a way to get 55. They said:

“I reached out to one of our engineers in Germany about this, and he said that for bikes with a 148 rear axle spacing, the Transmission system will be compatible with 52-55mm chain lines. There should not be any noticeable difference in the wear and lifespan of the components as a result of the chain line.”

If I understood support correctly, from other messages, they indicated 00.7918.280.002 will give me a 52mm chainline on my gen3 levo with a 36t chainring. This will require me to remove the chain guide, which I believe is fine, since the gen3 levo manual says “With the chain guide removed, a 36t chainring can be used.”

Sram support also told me by using a larger front chainring, I’ll better drivetrain life:

“Part of the reason that the kit comes with a 36T chainring is that most e-bikes have a max chainring size of 36T, and the size of the chainring can drastically affect the lifespan of the drivetrain.

We recommend using the largest compatible chainring for your e-bike due to the additional wear from motor torque. Chainring and groupset lifespan is almost doubled every time you add two teeth to the chainring. By using a larger chainring, the rider tends to use more gears in the center of the cassette with more teeth instead of the smaller gears, which wear out faster. When wear is spread out over a larger number of teeth on the cassette or chainring, it makes a huge difference in the lifespan of the components.”

So I’ll just get the kit I indicated and rock the 52mm chainline with the 36t chainring.

If anyone has an easy way to get a 55mm chainline with a 36t chainring, I’d still be interested to learn, though as I mentioned above, it looks like 52mm is alright.
 

Rich-H

Member
Apr 3, 2023
148
108
Hampshire
I talked to SRAM tech support about the topic. They were super helpful.

I was asking if the 52mm chain line is alright, or if I need to find a way to get 55. They said:

“I reached out to one of our engineers in Germany about this, and he said that for bikes with a 148 rear axle spacing, the Transmission system will be compatible with 52-55mm chain lines. There should not be any noticeable difference in the wear and lifespan of the components as a result of the chain line.”

If I understood support correctly, from other messages, they indicated 00.7918.280.002 will give me a 52mm chainline on my gen3 levo with a 36t chainring. This will require me to remove the chain guide, which I believe is fine, since the gen3 levo manual says “With the chain guide removed, a 36t chainring can be used.”

Sram support also told me by using a larger front chainring, I’ll better drivetrain life:

“Part of the reason that the kit comes with a 36T chainring is that most e-bikes have a max chainring size of 36T, and the size of the chainring can drastically affect the lifespan of the drivetrain.

We recommend using the largest compatible chainring for your e-bike due to the additional wear from motor torque. Chainring and groupset lifespan is almost doubled every time you add two teeth to the chainring. By using a larger chainring, the rider tends to use more gears in the center of the cassette with more teeth instead of the smaller gears, which wear out faster. When wear is spread out over a larger number of teeth on the cassette or chainring, it makes a huge difference in the lifespan of the components.”

So I’ll just get the kit I indicated and rock the 52mm chainline with the 36t chainring.

If anyone has an easy way to get a 55mm chainline with a 36t chainring, I’d still be interested to learn, though as I mentioned above, it looks like 52mm is alright.
Thanks for sharing.

Did SRAM confirm that the BROSE direct mount chainring won't give you a 55mm chain line on the LEVO?
 

pontoon

New Member
Apr 24, 2023
61
20
USA
Thanks for sharing.

Did SRAM confirm that the BROSE direct mount chainring won't give you a 55mm chain line on the LEVO?
They said “I mentioned this earlier, but the chainline is determined by the motor and the motor spider or the direct mount chainring. If you were to use one of our direct mountchainrings, you would get a 55mm chainline. Unfortunately, because of the offset on the Turbo Levo models, our Brose chainring is not compatible with that bike. That said, based on what our engineers and product teams have said, having a 52mm chainline would still be compatible with the Transmission system.”

Sram did indicate the following chainring is compatible in 34t:
11.6218.057.000 CHAIN RING T-TYPE 34T 104 BCD STEEL BLACK

They also suggested if I wanted a 55mm chainline, perhaps FSA or Specialized can make a part:
“Just so you are aware, we do not make a spider, so you would have to reach out to either FSA or Specialized about a different spider for a 55mm chain line if you end up deciding to go in that direction. “

I’m not sure what all to make of it tbh
 

blob

New Member
Feb 22, 2023
23
7
Croatia
The original Levo chainring is supposed to have a 52 mm chainline? And the new SRAM Brose chainring is 55 mm?

Well, if I compare them on a flat surface the difference between them is 6 mm, not 3 mm... :poop:

So, the Brose chainring will probably give a 57-58 mm chainline on the Levo.

IMG_2208.jpg
 
Last edited:

pontoon

New Member
Apr 24, 2023
61
20
USA
The original Levo chainring is supposed to have a 52 mm chainline? And the new SRAM Brose chainring is 55 mm?

Well, if I compare them on a flat surface the difference between them is 6 mm, not 3 mm... :poop:

So, the Brose chainring will probably give a 57-58 mm chainline on the Levo.

View attachment 113483
so the brose direct mount chainring is not compatible with the gen3 levo, as the support said, then?

If someone were to remove material from the direct mount chainring would it have a 55mm chain line? Sorry, I don’t really know how direct mount chainrings work.
 

Rich-H

Member
Apr 3, 2023
148
108
Hampshire
so the brose direct mount chainring is not compatible with the gen3 levo, as the support said, then?

If someone were to remove material from the direct mount chainring would it have a 55mm chain line? Sorry, I don’t really know how direct mount chainrings work.
The direct mount chainring should give you a 55mm chain line with a Brose motor but because the motor is offset on the Levo, you end up with around a 57mm chain line. You can remove 2mm off the chainring to give you a 55mm chain line.

The 104BCD chainring doesn't define the chain line, it's set by the spider. So the 104BCD chainring will give you a 52mm chain line with the standard spider. Specialized would either need to make a new spider with a different offset to give a 55mm chain line or you might be able to use a 3mm spacer behind the existing spider get a 55mm chain line.

Having said all this, SRAM are saying that a 52mm chain line is fine and I'm running an unmodified DM chainring without any issues (I currently have micro adjust set to 6). I can't say for certain that a 57mm won't cause additional wear but shifting etc. is fine.
 

G-Sport

Active member
Oct 7, 2022
234
179
Yorkshire
Is Transmission ever likely to get released in GX spec?
Probably. Axs did, probably be at least a year though.

What I want to know (as the owner of a non UDH bike) is if you can use the more durable cassette and chain with old fashioned cable actuated eagle derailleurs.
 

Rich-H

Member
Apr 3, 2023
148
108
Hampshire
Probably. Axs did, probably be at least a year though.

What I want to know (as the owner of a non UDH bike) is if you can use the more durable cassette and chain with old fashioned cable actuated eagle derailleurs.
I don't believe so as the Eagle Transmission cassettes moved outboard by 2.5mm.
 

G-Sport

Active member
Oct 7, 2022
234
179
Yorkshire
I don't believe so as the Eagle Transmission cassettes moved outboard by 2.5mm.
Yes, this is the main concern.
I don't really understand where this extra 2.5mm is coming from. As far as I remember, the original UDH specs didn't stipulate extra clearance around the area.
And does this mean that the sprocket pitch is wider, so the whole cassette is wider, or is there just less of a dish to the back of it?
 

Rich-H

Member
Apr 3, 2023
148
108
Hampshire
Yes, this is the main concern.
I don't really understand where this extra 2.5mm is coming from. As far as I remember, the original UDH specs didn't stipulate extra clearance around the area.
And does this mean that the sprocket pitch is wider, so the whole cassette is wider, or is there just less of a dish to the back of it?
Since there’s no derailleur hanger anymore, the XD driver body’s end cap sits directly against the derailleur body, not a dropout. SRAM moved the cassette outboard 2.5 mm to make up for that.
 

G-Sport

Active member
Oct 7, 2022
234
179
Yorkshire
Since there’s no derailleur hanger anymore, the XD driver body’s end cap sits directly against the derailleur body, not a dropout.
What?
There is no "end cap" on an XD driver? And if there was it would rotate with the cassette so how could it be "against the derailleur body"?
Do you mean that the hub axle collar is against the part of the derailleur that acts as the dropout (and replaces the UDH)?
That makes sense but the effective OLD would still need to be the same, and there would (presumably) still be a 3mm deep channel in this part to act as the location for the axle end-cap when installing the wheel.
So either the chain has to overhang the locating channel or the channel depth is reduced significantly. Either of which would need to be in the original UDH frame mating specifications to make sure the chain won't rub the stays but isn't.
 

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