Mahle SL 1.1 to SL 1.2 - What's Possible and What's Different ?

p3eps

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For the 1.2 motor I’d go with these.

I wish there was a weight published somewhere for these? They look sweet, and I'd quite like to drop from 170 to 165... but I'd like to know the weight v's the SRAM carbon ones that came as stock.
 

crawfishoo

New Member
Feb 1, 2024
11
9
Indiana
Thanks for the options. Most of these are outside the budget I'm willing to spend on my son's bike. I would love 5dev cranks but can't justify $400 cranks on my 7 year olds bike. And I would be sick putting said cranks into the mill to modify them down to 140mm.

It's a little frustrating that Specialized went through the effort change from the M30 mahle specific interface, yet replaced it with an equally unique Sram Dub interface. I asked Sram about e-bike Dub cranks, they responded that the only option is to purchase through specialized. Why couldn't they use a standard ISIS option like every other ebike out there??!!? Grumble ha

So the search continues. Some basic aluminum cranks I can cut down to 130-140mm to fit my son's bike. If I do swap motors it appears I can use the OE 1.1 praxis cranks and cut down to ~140mm
 
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G-Sport

Active member
Oct 7, 2022
291
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Yorkshire
It's not just them to be fair. Fazua use the Etor interface and Shimano use theirs. ISIS is a pretty crap outdated standard at this point so I can see why they wouldn't want to use that. Mahle have actually signed up to the Etor standard so the next Mahle motor might use that..
The Shimano standard is very very good but again not easy to get shorter cranks.
 

crawfishoo

New Member
Feb 1, 2024
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Its interesting that Sram is not even using the Dub interface on the new powertrain motors. Looks like the SL1.2 is going to be truly unique to Specialized.
 

Streddaz

Active member
Jul 7, 2022
276
389
Tasmania
Its interesting that Sram is not even using the Dub interface on the new powertrain motors. Looks like the SL1.2 is going to be truly unique to Specialized.
The Sram motor is just a Brose motor which was developed for Specialized in the first place. Unfortunately, they all seem to have their own different choices when it comes to cranks.
 

davem85

Member
Feb 1, 2021
47
16
Germany
Anyone here actually swapped the 1.2 motor from the kids HT LSL?
You can currently get it for only 2k€ in Germany.

I was wondering
- how to remove the limitation
- if the stock 155mm cranks are usable for adults
- compatibility of the chainring with non-Transmission AXS
- if there might some kind of preselection going on for the motors going in kids bikes

Any ideas?
Thanks guys.
 

MatCret

New Member
Jan 21, 2024
39
22
France, FarWest France
Anyone here actually swapped the 1.2 motor from the kids HT LSL?
You can currently get it for only 2k€ in Germany.

I was wondering
- how to remove the limitation
- if the stock 155mm cranks are usable for adults
- compatibility of the chainring with non-Transmission AXS
- if there might some kind of preselection going on for the motors going in kids bikes

Any ideas?
Thanks guys.
Hi!
I'm an adult and I use the kids HT LSL' cranks on a KENEVO SL2, mullet. I weight more than a fat kid... 70kg...
 

crawfishoo

New Member
Feb 1, 2024
11
9
Indiana
Anyone here actually swapped the 1.2 motor from the kids HT LSL?
You can currently get it for only 2k€ in Germany.

I was wondering
- how to remove the limitation
- if the stock 155mm cranks are usable for adults
- compatibility of the chainring with non-Transmission AXS
- if there might some kind of preselection going on for the motors going in kids bikes

Any ideas?
Thanks guys.

I completed this swap last month. I had the same questions as you and didn't find any clear answers so hopefully this helps. I did the swap on my 2021 Gen 1 Alloy Levo SL. Keep the hardware with the bike, not the motors, at least for the alloy frame there was unique hardware that stays with the bike. The skid plate fitment was the biggest issue, both plates had to be modified and took a lot of grind and fit checks to make them work. My son is barely 48" so I modified the stock SL 1.1 cranks to 130mm, fits him great now. 155mm cranks are still WAY to long for a 24" kids bike IMO.

- how to remove the limitation
* A Specialized dealer can reprogram the ECU to the standard Levo SL software, however my dealer would not do this and discouraged me from doing such for warranty purposes. If the software doesn't match the bike/motor some dealers might not be as friendly for warranty replacement if needed. I purchased a SPEEDi device. It has worked great and gives me 22 MPH speed capability. The display does not show the correct speed but I use my Garmin for tracking rides. SPEEDi - E-Bike Speed Limit Increaser by NLS Components

- if the stock 155mm cranks are usable for adults
* As far as strength; they are the same forging as the adult cranks, pedal hole is just drilled and tapped at 155mm. They will be just as strong as "Adult" Levo SL crank arms. Depending on your height and riding terrain, crank arm length is really subjective to personal preference. I am 6"1' and ride mostly flowing XC terrain, I wanted longer crank arms. I traded my 155mm cranks for a set of 165mm arms with a member on a Levo SL Facebook group.

- compatibility of the chainring with non-Transmission AXS
* I have been using X-Sync 2 chainring(s) on multiple bikes with full Shimano XT 11 speed drivetrains. Has worked great. Obviously you cant mix & match with 12 speed Shimano, but the 11 speed parts work fine together. If you are asking about standard AXS, the chainring will work great with any SRAM 12 speed group set.

- if there might some kind of preselection going on for the motors going in kids bikes
* I don't think there is. I noticed the extra torque and reduced noise from the SL 1.2 motor from my sons bike. According to the Specialized app I get the full 320 watts of output on the kids 1.2 SL motor. I like the new motor, its an improvement but its not completely life changing.

Now that I have done the swap and figured out some of challenges I am happy with it. However, if I were to go back in time with my current knowledge, I would likely forgo the swap and leave both bikes as-is.

If you have any specific questions, let me know I will try to help you out.
 

sdcoffeeroaster

Active member
Jul 22, 2018
563
209
San Diego, CA
I completed this swap last month. I had the same questions as you and didn't find any clear answers so hopefully this helps. I did the swap on my 2021 Gen 1 Alloy Levo SL. Keep the hardware with the bike, not the motors, at least for the alloy frame there was unique hardware that stays with the bike. The skid plate fitment was the biggest issue, both plates had to be modified and took a lot of grind and fit checks to make them work. My son is barely 48" so I modified the stock SL 1.1 cranks to 130mm, fits him great now. 155mm cranks are still WAY to long for a 24" kids bike IMO.

- how to remove the limitation
* A Specialized dealer can reprogram the ECU to the standard Levo SL software, however my dealer would not do this and discouraged me from doing such for warranty purposes. If the software doesn't match the bike/motor some dealers might not be as friendly for warranty replacement if needed. I purchased a SPEEDi device. It has worked great and gives me 22 MPH speed capability. The display does not show the correct speed but I use my Garmin for tracking rides. SPEEDi - E-Bike Speed Limit Increaser by NLS Components

- if the stock 155mm cranks are usable for adults
* As far as strength; they are the same forging as the adult cranks, pedal hole is just drilled and tapped at 155mm. They will be just as strong as "Adult" Levo SL crank arms. Depending on your height and riding terrain, crank arm length is really subjective to personal preference. I am 6"1' and ride mostly flowing XC terrain, I wanted longer crank arms. I traded my 155mm cranks for a set of 165mm arms with a member on a Levo SL Facebook group.

- compatibility of the chainring with non-Transmission AXS
* I have been using X-Sync 2 chainring(s) on multiple bikes with full Shimano XT 11 speed drivetrains. Has worked great. Obviously you cant mix & match with 12 speed Shimano, but the 11 speed parts work fine together. If you are asking about standard AXS, the chainring will work great with any SRAM 12 speed group set.

- if there might some kind of preselection going on for the motors going in kids bikes
* I don't think there is. I noticed the extra torque and reduced noise from the SL 1.2 motor from my sons bike. According to the Specialized app I get the full 320 watts of output on the kids 1.2 SL motor. I like the new motor, its an improvement but its not completely life changing.

Now that I have done the swap and figured out some of challenges I am happy with it. However, if I were to go back in time with my current knowledge, I would likely forgo the swap and leave both bikes as-is.

If you have any specific questions, let me know I will try to help you out.
Great review and still considering this. The price is now $3249. for the kids bike. I only found one reference to anything about speed in reviews and they called it class 1 which is 20 mph. They also said this is settable in the app. Would the std 1.1 TCU and/or battery work? I'm not clear on this issue. Like you said this might not be worth the extreme effort and then you have to sell the kids bike with the less powerful motor. Oh how did you modify the Sl crank arms? Thanks
 

crawfishoo

New Member
Feb 1, 2024
11
9
Indiana
I had planned to get my son the kids SL anyways so swapping motors was just an added perk. I personally would not do it unless I was keeping the kids bike.

The kids Levo SL has a lower speed cutoff than the adult TCU. The kids TCU can be setup by a Specialized dealer for either 10 or 15 MPH. You can not change the speed or tire diameter in the app. If your specialized dealer is willing they can flash the TCU with the standard SL. 1.2 software. My dealer was not willing to do that and said it would void my warranty.

And for clarity. You cannot just swap the motors. You have to swap the battery and TCU with the motor to get the extra power.
 

sdcoffeeroaster

Active member
Jul 22, 2018
563
209
San Diego, CA
I had planned to get my son the kids SL anyways so swapping motors was just an added perk. I personally would not do it unless I was keeping the kids bike.

The kids Levo SL has a lower speed cutoff than the adult TCU. The kids TCU can be setup by a Specialized dealer for either 10 or 15 MPH. You can not change the speed or tire diameter in the app. If your specialized dealer is willing they can flash the TCU with the standard SL. 1.2 software. My dealer was not willing to do that and said it would void my warranty.

And for clarity. You cannot just swap the motors. You have to swap the battery and TCU with the motor to get the extra power.
Thanks. I was trying to get the S2 Turbo LEVO when they had the big sale on the carbon model and ended up with the S3 (paid $3500. and traded the 700 wh battery for a set of Roval CF rims) which is a lot longer and more reach then my medium Sl which is just right. Love the Levo's power though and I've tweaked things so it's rideable for me just not ideal. And I love my 38 lb SL but could use a bit more power, lol. Just looking for options and maybe if they ever just sell the 1.2 motor with some sort of TCU upgrade.
 

G-Sport

Active member
Oct 7, 2022
291
227
Yorkshire
Thanks for the very helpful answers everyone.
I was contemplating this swap too. I only have a few months left on my 2022 Gen1 Levo SL warranty anyway, but I have no use for the actual 24" bike so would either need to try to sell it with the 1.1 motor battery and TCU, or sell what parts I can and keep my old motor as a backup (which is quite attractive) but I doubt I would get much for the wheels, forks etc. Either way it is likely to be quite expensive.
If I keep the frame then presumably I can always put everything back in it to warranty if I need to? Might be a bit weird taking it to the shop in that form but would at least be an option rather than having zero options.

On the plus side. UK speed limit is about 15mph anyway (though my SL seems happy to help up to about 16.5) and 15mph on a 24" wheel would be about 17 on a 27.5" and 18 on a 29". I also suspect that my dealer might be willing to do the necessary re-flash if I ask nicely.

My battery is now at 90% which is annoying, my garmin is getting very long in the tooth and is slightly broken and I'd like to save the weight and tidy things up by just using the Mastermind TCU so there are more benefits than just the quietness and extra power.

If the bike comes down in price anymore or is still available when my warranty runs out then I will almost certainly do it. Or I may just talk myself into it before then.
 

iamanej

Member
Apr 3, 2023
55
23
Slovenija
I believe that the difference in power between 1.1 an 1.2 is subtle and it would drain you battery quicker.
I would change it if let's say battery would be upgraded to around 450wh (new technology should be able to provide that with the same weight).
I have a custom range extender weighting 2.0kg and having 480wh.
 

p3eps

E*POWAH Elite World Champion
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Dec 14, 2019
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I believe that the difference in power between 1.1 an 1.2 is subtle and it would drain you battery quicker.
I would change it if let's say battery would be upgraded to around 450wh (new technology should be able to provide that with the same weight).
I have a custom range extender weighting 2.0kg and having 480wh.
This is true if you are riding the bike at the same setting at the 1.1. If you run 60/60 on the 1.1 and run 60/60 on the 1.2, you'd notice both a difference in the power the motor supplies, and also the amount of battery it uses.
Due to the extra 15Nm, the equivalent setting on the 1.2 might be more like 40/40 to give your legs the same support as the 1.1. on 60/60 If you manage to find the equivalent setting, the 1.2 is actually more efficient.

I ran my 1.1 in 30/80 the majority of the time. I find that the equivalent setting on my 1.2 is around 15/35 (according to my legs / laptimes!) and when using this setting I have marginally more battery left on the same ride.

Obviously if I was to rip round in 100/100 on both bikes, the 1.2 would use more battery on the same ride... but could potentially do it a bit quicker.

For me, the 1.2 Levo SL is a huge upgrade - but that's primarily the frame / geometry rather than the motor. Having the extra 15Nm, quieter motor and Mastermind TCU are a bonus.
 

sdcoffeeroaster

Active member
Jul 22, 2018
563
209
San Diego, CA
This is true if you are riding the bike at the same setting at the 1.1. If you run 60/60 on the 1.1 and run 60/60 on the 1.2, you'd notice both a difference in the power the motor supplies, and also the amount of battery it uses.
Due to the extra 15Nm, the equivalent setting on the 1.2 might be more like 40/40 to give your legs the same support as the 1.1. on 60/60 If you manage to find the equivalent setting, the 1.2 is actually more efficient.

I ran my 1.1 in 30/80 the majority of the time. I find that the equivalent setting on my 1.2 is around 15/35 (according to my legs / laptimes!) and when using this setting I have marginally more battery left on the same ride.

Obviously if I was to rip round in 100/100 on both bikes, the 1.2 would use more battery on the same ride... but could potentially do it a bit quicker.

For me, the 1.2 Levo SL is a huge upgrade - but that's primarily the frame / geometry rather than the motor. Having the extra 15Nm, quieter motor and Mastermind TCU are a bonus.
Yes I find the newer Turbo Levo (and SL geometry an upgrade except for the much longer reach of 452mm and resulting RAD for my size. The longer wheelbase is not noticeable over my medium SL except that the smaller medium SL feels more maneuverable/flickable/lively and some of that is weight 38 vs 47lbs, etc. The fork angle of the newer bikes really helps on downhill confidence which is why the S2 Levo would have been the perfect combination for me. My dealer, a specialized owned dealership, scoured the country for an S2 at the time and we though we had found several a couple of times but always came up empty so I went for the great price and bought the S3. It does feel big for my 5'7" height and 30" inseam and some adjustments helped: lowered dropper, raised bars (50mm with 10mm stem spacer) and I'm going to try some 140mm crank arms soon (low risk and found PROWHEEL ISIS crank arms, available as short as 130mm!!).

But looking at things like reach, wheelbase and top tube length the S2 is very much like my 2022 sl medium. Since I replaced the forks on my 2023 Turbo with some Lyrik Ultimates I have I ended up with a trail reducing 51mm offset which makes the bigger bike a bit more maneuverable in the tight stuff. I plan to shorten my bars some more too. I'm at 750mm bar width, short for most, but I think 720mm or so might help for the type of trail riding I do, not a downhiller or jumper at my 75 yr age, lol.

Oh I might add that a local dealer here in San Diego will sell the kids SL for $3000. including shipping.
 

p3eps

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Wow, that is amazing, $2186. USD I guess I would jump at the chance to get one in that case. That kids bike must not be selling very well.
Clearly not... every retailer is selling them for half price (£1750). All colours available too.
 

G-Sport

Active member
Oct 7, 2022
291
227
Yorkshire
Just noticed that the Specialized Store lists the TCU as "Specialized TCU, 10-LED State of charge, 3-LED Ride Mode display" which would make it the old one, pictures still show the mastermind though. Worth double checking before buying if anyone is jumping on this.
 

sdcoffeeroaster

Active member
Jul 22, 2018
563
209
San Diego, CA
Clearly not... every retailer is selling them for half price (£1750). All colours available too.
OK my dealer just told me he can now get me the 1.2 motor and battery for $1650. He doesn't say anything about the TCU.

I understood the old TCU will not work with the new motor or will not allow it to perform any different from the old motor. Does anyone know, based on experience if this absolutely true????

Ok just talked to Specialized and they are NOT offering or endorsing any 1.1 to 1.2 Sl upgrades at this time. Just to be clear, lol.
 
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p3eps

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OK my dealer just told me he can now get me the 1.2 motor and battery for $1650. He doesn't say anything about the TCU.

I understood the old TCU will not work with the new motor or will not allow it to perform any different from the old motor. Does anyone know, based on experience if this absolutely true????

Ok just talked to Specialized and they are NOT offering or endorsing any 1.1 to 1.2 Sl upgrades at this time. Just to be clear, lol.
I’m not sure anybody knows the 100% answer to this.
The belief is that the TCU contains a version of firmware that works with the SL1.2 motor… which will not be on your TCU if you have a 1.1 motor.

Everyone who has swapped a motor onto their 1.1 bike has swapped the TCU AND battery to make sure it works properly.

I would imagine if you had a friendly dealer, they could possibly re flash your old TCU to work with the 1.2 motor… but I don’t think anyone has done that yet.
 

sdcoffeeroaster

Active member
Jul 22, 2018
563
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San Diego, CA
I’m not sure anybody knows the 100% answer to this.
The belief is that the TCU contains a version of firmware that works with the SL1.2 motor… which will not be on your TCU if you have a 1.1 motor.

Everyone who has swapped a motor onto their 1.1 bike has swapped the TCU AND battery to make sure it works properly.

I would imagine if you had a friendly dealer, they could possibly re flash your old TCU to work with the 1.2 motor… but I don’t think anyone has done that yet.
And of course Spec is taking the hands off approach to all of this for now saying they don't recommend any of it and they even said they've NOT being able to do this, implying they tried but failed, lol, which I don't believe. I think they must know the answer if the old TCU can be re-flashed but saying anything is endorsing it, which they won't do.
 

Dax

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Specialized Switzerland has 24" kids sl on sale for Chf2000, so swap the lot and sell the 24 for 1000. Feasible?

If anyone buys the kids bike. And it would be lower speed limit due to wheel size change. Still tempting even if I only get £500 for the kids bike, still cheaper than buying a KSL2 and selling my KSL.
 

Zimmerframe

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If anyone buys the kids bike. And it would be lower speed limit due to wheel size change. Still tempting even if I only get £500 for the kids bike, still cheaper than buying a KSL2 and selling my KSL.
Wouldn't you end up with a higher speed cut-off ? A larger wheel will have a bigger circumference, so it will go further for each revolution, therefore, you'll be going faster if the wheels are turning at the same RPM.

Can't you keep it as a funky little dirt jump/bmx esq play bike ?
 

p3eps

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Wouldn't you end up with a higher speed cut-off ? A larger wheel will have a bigger circumference, so it will go further for each revolution, therefore, you'll be going faster if the wheels are turning at the same RPM.

Can't you keep it as a funky little dirt jump/bmx esq play bike ?
That makes sense... I have a 29" rear on my Levo SL, and the Mastermind always displays a lower speed than my Garmin as it thinks it's a 27.5". It means I get about an extra mph before my speed cutoff!
With a 24" wheel, you'd probably get a few extra mph.
 

Dax

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Wouldn't you end up with a higher speed cut-off ? A larger wheel will have a bigger circumference, so it will go further for each revolution, therefore, you'll be going faster if the wheels are turning at the same RPM.

Can't you keep it as a funky little dirt jump/bmx esq play bike ?

I meant the kids bike I would try to sell would have a lower limit. My bike would have a higher limit.
 

sdcoffeeroaster

Active member
Jul 22, 2018
563
209
San Diego, CA
So to clarify, the std 1.1 Sl with the 1.2 motor and TCU/battery swap would still think it had the smaller circumference wheel (without a firmware change...if that is even possible/compatible) and at the the max kids bike setting of 15 mph you would really be going much faster, maybe 18 mph if you just looked at the rim ratio of 29/24 (pie X D = circumference), but not too far off from 20 mph. The actual diameter ratio might be slightly different with tires. Close enough to 20 mph so why did Crawfishoo, who already did this swap, install the Speedi mechanism to get 22 mph? That part of his swap really doesn't seem to worth the added complexity. Have to ask him if he tried the speed limit prior to installing the Speedi.

Now the kids bike with the 1.1 motor/battery and TCU will not be going 20 mph when the TCU thinks it's hit that limit because of the 24" rims and will instead top out at about 17.7 mph.....still above the kids bike two limits of 10 mph and 15 mph. Oh just realized the new Sl is 27.5" on the back, mullet....so only 17 mph.

Has anyone else reading this thread done the kids bike swap and can report their results to us?
 
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