Non-Shimano HG Freehub on a Hub Motor?

[NaCly]

Hi ES, it's my first post here and I'm already stumped by my own overzealous, careless planning.

I'm trying to convert a Marlin 7 Gen 3 with an RH212 hub motor, and discovered that the bike has an SRAM Eagle SX groupset. The RH212 hub motor has a standard Shimano HG cassette freehub like most others, and I was wondering if I could do one of the following:

1. Use an HG-compatible cassette on the hub motor; the tricky thing is that the groupset I have is 12-speed, and I don't know if there are any 12-speed, SRAM Eagle compatible cassettes that also mount on an HG body. Does anyone know if there is one?

2. Swap the freehub; on Grin Tech's RH212 disassembly video (5:20), the freehub assembly seems to be one-piece, but there is a bearing on the inside. This makes me wonder if I could swap the freehub to the SRAM Eagle one, but I don't know if it's possible to disassemble the freehub from the 6-bolt part that mounts the splined part onto the hub motor. I really do not want to do this and might even consider swapping the entire groupset before I break the seal on my already Statorade-injected hub motor. If the freehub assembly cannot be further disassembled, then I might even seek for somebody to CAD model and manufacture one for me. It all comes down to cost.

Thank you for reading,

NaCly

 

[amberwolf]

Chalo probably has the answer right off the top of his head, but baased on a few minutes poking around all i can see is that they aren't directly swappable.

for the very few i've had apart, the freehub bodies on normal bike hubs and those on motor hub side covers are different in how they mount on, so i don't know that you could get the sx fh to mount to the hubcover, without as you say having someone modeling and making the part for you to let them mate up...and that's assuming that the sx fh has a large enough id to fit over the axle shoulder / bearing of the hub cover; it might not.

for instance, here's what the grin gmac loosk like inside; on it the fh body screws into the side cover, which is actualy why this carnage occured because somehow the fh began to unscrew and wihtout a chain/sprocket on there to keep it from proceeding it ended u p undoing enough to aloow the hub case to slide over enough to drag on the pcb inside, and ....well, oops.

The SB Cruiser : Amberwolf's 2WD Heavy Cargo Trike & Dog Carrier

clamping / pinching dropouts both ends, tight and flat to axle both ends both sides, no nuts needed on either side (have one on outside anyway just because there's axle length for it) is hubmotor with solid axles, can't see anything like qr axles or hollow ones? shear was at shoulder of axle...

endless-sphere.com

anywah these are the fh on the cover and the cover with the fh unscrewed

https://endless-sphere.com/sphere/attachments/20231002_130026-jpg.340423/

https://endless-sphere.com/sphere/attachments/20231002_120003-jpg.340410/

 

[Chalo]

Shimano standard 8-9-10 speed cassettes are prevalent on hub motors. 11 speed and 12 speed are their own respective standards, different in width than the interchangeable 8-9-10.

My advice is that you drop 12 speed like a hot rock and get with the 8 speed Microshift Acolyte family. You'll thank me later.

 

[marvin78]

My advice is that you drop 12 speed like a hot rock and get with the 8 speed Microshift Acolyte family. You'll thank me later.

What are the advantages of Microshift over say another budget option like L-twoo?

 

[NaCly]

Chalo probably has the answer right off the top of his head, but baased on a few minutes poking around all i can see is that they aren't directly swappable.

for the very few i've had apart, the freehub bodies on normal bike hubs and those on motor hub side covers are different in how they mount on, so i don't know that you could get the sx fh to mount to the hubcover, without as you say having someone modeling and making the part for you to let them mate up...and that's assuming that the sx fh has a large enough id to fit over the axle shoulder / bearing of the hub cover; it might not.

for instance, here's what the grin gmac loosk like inside; on it the fh body screws into the side cover, which is actualy why this carnage occured because somehow the fh began to unscrew and wihtout a chain/sprocket on there to keep it from proceeding it ended u p undoing enough to aloow the hub case to slide over enough to drag on the pcb inside, and ....well, oops.

The SB Cruiser : Amberwolf's 2WD Heavy Cargo Trike & Dog Carrier

clamping / pinching dropouts both ends, tight and flat to axle both ends both sides, no nuts needed on either side (have one on outside anyway just because there's axle length for it) is hubmotor with solid axles, can't see anything like qr axles or hollow ones? shear was at shoulder of axle...

endless-sphere.com

anywah these are the fh on the cover and the cover with the fh unscrewed

https://endless-sphere.com/sphere/attachments/20231002_130026-jpg.340423/

https://endless-sphere.com/sphere/attachments/20231002_120003-jpg.340410/

View attachment 365210 View attachment 365211 View attachment 365212

I figured that replacing the freehub would prohibitively costly. I found a company that makes cross-compatible cassettes, and they claim that this one works with both HG hubs and SRAM 12 speed MTB derailleurs. I asked them about my specific case and will update once they reply.

 

[lnanek]

Not entirely sure what this thing is, but I suspect it might be an adapter from SRAM SX to e*thirteen microspline:

E.Thirteen Microspline Freehub Kit | Jenson USA

EThirteen Microspline Freehub Kit OE Replacement Parts Replace your worn old freehub body with the EThirteen Microspline Freehub Kit. It fits all EThirteen hubs and is also compatible with TRSLG1 series hubs as well as EThirteens newest line of ESPEC and XCX hubs. The EThirteen Microspline...

www.jensonusa.com

Then e*thirteen has various cassettes for Shimano HG and their own microspline that they say are compatible with both Shimano and SRAM derailleurs:

E*Thirteen Helix Plus2 Speed Cassette | Jenson USA

EThirteen Helix Plus 12 Speed Cassette Big gearing for big rides EThirteenrsquos Helix Plus cassette is a unique cassette in that unlike other 12speed MTB cassettes it offers a 9tooth cog for a top end gear. Just like your typical 12speed MTB cassette it utilizes a 50tooth cog for the lowest...

www.jensonusa.com

 

[NaCly]

I figured that replacing the freehub would prohibitively costly. I found a company that makes cross-compatible cassettes, and they claim that this one works with both HG hubs and SRAM 12 speed MTB derailleurs. I asked them about my specific case and will update once they reply.

Ended up calling just now and they said it's not a perfect product -- they're having issues with both Shimano and SRAM 12 speed derailleurs, and a new version is coming out in April.

 

[Chalo]

I figured that replacing the freehub would prohibitively costly. I found a company that makes cross-compatible cassettes, and they claim that this one works with both HG hubs and SRAM 12 speed MTB derailleurs. I asked them about my specific case and will update once they reply.

Since the difference between 11 or 12 speed Shimano Hyperglide freehubs and other gear counts is only the total spline width, you can subtract one sprocket (I think minus just one will do) and install the rest of them onto an 8/9/10 speed body. Then set the derailleur limits to the remaining stack by using the limit screws. The last click in the shifter won't do anything, but otherwise it will function as normal.

 

[Chalo]

What are the advantages of Microshift over say another budget option like L-twoo?

Probably no real difference in terms of performance, but Acolyte 8/Advent 9/Advent X are cheap, durable, reliable, and widely available. The shifters and derailleurs are specific to those product lines and not compatible with other brands, but the cassette spacings and mounting splines are standard Shimano Hyperglide spec for their respective gear counts.

 

[PaPaSteve]

Compatibility chart :

O-bike | teknisk_info

obike.dk

Sunrace cassette might work ?

CSMZ90 WA5

MZ 12-speed wide-ratio cassette for Sram® 12-speed

sunrace.com

 

[marvin78]

L-Twoo is also compatible with the old Shimano stuff, it's the only reason I could mix my old Deore rapidfire shifter with the L-twoo AX7 derrailleur while also giving me a 11-46t cassette option.

I'm not 100% happy though, I've had some kind off backward reaction sometimes when I stop peddaling, chain is no longer in motion but when I upshift there is tension enough on the chain to cause the derrailleur to jump ( not gears, it jumps in place on the cassette but nearly folds back on itself ). I never had that with my old XT derrailleur, but that one didn't allow a higher range cassette, but I'm like 99% sure it's the derrailleur and not something else I changed like firmware settings, mainly because the chain is no longer in motion when it happens so it can't be motor related I figure.

I almost don't need the higher range with the assistance, but then again I've not had to pull my cargo carts fully loaded.

Otherwise I probably would have went with something with the max chain width I could use with acceptable gear range, but that's not an issue when using a hub motor I guess.

 

[NaCly]

Not entirely sure what this thing is, but I suspect it might be an adapter from SRAM SX to e*thirteen microspline:

E.Thirteen Microspline Freehub Kit | Jenson USA

EThirteen Microspline Freehub Kit OE Replacement Parts Replace your worn old freehub body with the EThirteen Microspline Freehub Kit. It fits all EThirteen hubs and is also compatible with TRSLG1 series hubs as well as EThirteens newest line of ESPEC and XCX hubs. The EThirteen Microspline...

www.jensonusa.com

Then e*thirteen has various cassettes for Shimano HG and their own microspline that they say are compatible with both Shimano and SRAM derailleurs:

E*Thirteen Helix Plus2 Speed Cassette | Jenson USA

EThirteen Helix Plus 12 Speed Cassette Big gearing for big rides EThirteenrsquos Helix Plus cassette is a unique cassette in that unlike other 12speed MTB cassettes it offers a 9tooth cog for a top end gear. Just like your typical 12speed MTB cassette it utilizes a 50tooth cog for the lowest...

www.jensonusa.com

Hi ES, it's my first post here and I'm already stumped by my own overzealous, careless planning.

I'm trying to convert a Marlin 7 Gen 3 with an RH212 hub motor, and discovered that the bike has an SRAM Eagle SX groupset. The RH212 hub motor has a standard Shimano HG cassette freehub like most others, and I was wondering if I could do one of the following:

1. Use an HG-compatible cassette on the hub motor; the tricky thing is that the groupset I have is 12-speed, and I don't know if there are any 12-speed, SRAM Eagle compatible cassettes that also mount on an HG body. Does anyone know if there is one?

2. Swap the freehub; on Grin Tech's RH212 disassembly video (5:20), the freehub assembly seems to be one-piece, but there is a bearing on the inside. This makes me wonder if I could swap the freehub to the SRAM Eagle one, but I don't know if it's possible to disassemble the freehub from the 6-bolt part that mounts the splined part onto the hub motor. I really do not want to do this and might even consider swapping the entire groupset before I break the seal on my already Statorade-injected hub motor. If the freehub assembly cannot be further disassembled, then I might even seek for somebody to CAD model and manufacture one for me. It all comes down to cost.

Thank you for reading,

NaCly

Found out that the SRAM SX cassette does use the HG freehub because it's the cheapest, and I suspect a lot of OEMs including Trek want these so they don't have to add a new wheel SKU with the XD freehub. Trek added a dropper post to the latest marlin 7, but cut some cost by downgrading the drivetrain from Deore to SX.

Grin's website claims that the HG freehub on the FH212 supports up to 11 speeds, so I'll just have to experiment. If it doesn't work, I'm probably going to do an 11 speed cassette with the derailleur limit that Chalo suggested.

Thank you everyone for your suggestions.

 

[Chalo]

Grin's website claims that the HG freehub on the FH212 supports up to 11 speeds, so I'll just have to experiment. If it doesn't work, I'm probably going to do an 11 speed cassette with the derailleur limit that Chalo suggested.

Note that 11 and 12 speed don't have the same spacing or shifter pull ratio, so you can't use an 11 speed cassette with a 12 speed shifter. 5, 6, 7, 8, and 9 speed had a lot of derailleur to shifter intercompatibility, but starting with 10 speed, manufacturers decided it was better business to make you replace every component when you add a gear.

That's the main reason I let them keep whatever 10+ speed components they wanted me to buy. 8 speed is the sweet spot for economy, durability, function, fault tolerance, and range of available options.