Q128C freehub replacement

[barod]

Hi all,
I've had my ebike serviced today (5000 miles and going strong ), and the mechanic reckons I might need to source a replacement freehub before too much longer. Does anyone know what would be compatible with the Q128C please?

 

[Nealh]

Any 9 speed mtb or road one will do the job which has the standard splines/key way fitting.

Sram PG50.
Shimano HG50 , HG200 - 400.
Shimano MTB like M770 etc, Deore/XT.
Sunrace cassettes.

All will fit just depends on how much you want to spend and gearing needed.

https://www.ebay.co.uk/itm/Shimano-Alivio-Sora-HG400-9-Speed-MTB-Cassette-11-36/311921196930?epid=21005862097&hash=item489ff3bf82:g:xisAAOSwOgdYwnD8:rk:6:pf:0

https://www.ebay.co.uk/itm/New-Sram-Powerglide-PG-950-9-Speed-Cassette-11-32T-For-MTB-Road-Bike/273247460391?epid=1905387655&hash=item3f9ed15c27:g:RDMAAOSw1-5bEBhE:rk:9:pf:0

https://www.ebay.co.uk/itm/New-Sram-Powerglide-PG-950-9-Speed-Cassette-11-32T-For-MTB-Road-Bike/273247460391?epid=1905387655&hash=item3f9ed15c27:g:RDMAAOSw1-5bEBhE:rk:9:pf:0

https://www.ebay.co.uk/itm/SRAM-PG-950-PowerGlide-Road-Bike-Cassette-9-Speed-11-32/223219083765?_trkparms=aid=555017&algo=PL.CASSINI&ao=1&asc=20170912102133&meid=d5fb8a528ccc4fc19c1e3c6234e2f7e1&pid=100754&rk=1&rkt=1&&itm=223219083765&_trksid=p2045573.c100754.m4842

 

[barod]

Any 9 speed mtb or road one will do the job which has the standard splines/key way fitting.

Sram PG50.
Shimano HG50 , HG200 - 400.
Shimano MTB like M770 etc, Deore/XT.
Sunrace cassettes.

All will fit just depends on how much you want to spend and gearing needed.

Ah that's great to hear, thank you.

 

[barod]

Ah that's great to hear, thank you.

Whoops, spoke too soon. Those links are all cassettes, I was asking about the freehub body. How easily can replacements for that be obtained?

 

[Nealh]

My bad didn't read proper.
I wasn't able to remove the freehub body from my Q128C but ex member d8veh said it was easy.
No matter what I couldn't budge it !!!
My guess it will be a fairly std part.

 

[wheeliepete]

AFAIK no spares are available for Q motors, but that dosn't mean it is unrepairable. It may mean a strip down of your motor, but I'm pretty sure parts could be found from Shimano or Sram to fix.

 

[barod]

Thanks Nealh, I've seen the thread where you and D8veh talked about that. I hope I have an easier time when it finally comes to it. And thanks too wheeliepete, let's hope you're right about compatibility

 

[barod]

Hi again, resurrecting this post.
After 10,000 miles of faithful service the freehub on my Q128C finally gave up the ghost a couple of weeks ago. Long story, but my LBS mechanic has managed to remove it - unlike other posters, who say it just slides off, this one was actually screwed to the motor body - hence no amount of pulling was ever going to get it off.
Mechanic says it's like nothing he's ever seen before - I've posted his photos of it. Does anyone recognise this, and if so can they suggest where we might source a replacement? Someone elsewhere has suggested it might be a Bafang freehub?

 

[Nealh]

Good job Barod, having tried twice I hadn't figured it was threaded.
Do yo know how easily the lbs managed to remove it ?
I haven't actually looked to deep in the freehub body but assume there must be an Allen key socket in there for a 10 or12 mm key ?

Some here on SJS though thread dia looks too small.

Shimano Freehub Bodies | Hub Spares | Wheels | SJS Cycles

Splined bodies onto which the cassette slides and is held in place by a lockring

www.sjscycles.co.uk

 

[Nealh]

My Bafang cassette freehub body simply slides off .

The Q's are clones or the real deal form Aikema so the threaded option may be an in house design and machined by AKM.

 

[vfr400]

Why do you want to replace it? What's actually wrong with it?

You can buy a complete motor from BMSbattery and swap the side-plate - $157.28 inc shipping.
.

 

[Nealh]

Last time I looked prices up a bit now $200/£151 inc delivery.

 

[barod]

Thanks for the quick replies. Leaving aside the cost consideration of a buying a new motor just because the freehub is shot, I generally prefer to repair rather than replace (e.g. inner tubes)
Nealh, the LBS told me they blowtorched the area (from the inside of the cover, once they'd got it off - which was after they'd fab'd a lever for the job, and it still took 2 of them to get it off) before it unscrewed, but it came off with the same 2-pronged tool that you use to take out the bearings and service/ replace them.
Good point about AKM in house design - i'll get in touch and see it they can ship any separately. Otherwise (failing the final option of a new motor) it's going to be a question of doing as much as possible with the pawls and bearings to keep the freehub going - it's developed a nasty tendency of skipping/ slipping, which isn't nice when it happens as you're pulling away at traffic lights or junctions

 

[vfr400]

Last time I looked prices up a bit now $200/£151 inc delivery.

It's changed then. The price I mentioned is the latest.

 

[vfr400]

Thanks for the quick replies. Leaving aside the cost consideration of a buying a new motor just because the freehub is shot, I generally prefer to repair rather than replace (e.g. inner tubes)
Nealh, the LBS told me they blowtorched the area (from the inside of the cover, once they'd got it off - which was after they'd fab'd a lever for the job, and it still took 2 of them to get it off) before it unscrewed, but it came off with the same 2-pronged tool that you use to take out the bearings and service/ replace them.
Good point about AKM in house design - i'll get in touch and see it they can ship any separately. Otherwise (failing the final option of a new motor) it's going to be a question of doing as much as possible with the pawls and bearings to keep the freehub going - it's developed a nasty tendency of skipping/ slipping, which isn't nice when it happens as you're pulling away at traffic lights or junctions

I haven't had any problems with my Q128C, but I know other cassette motors gave the problem you described. In them, it was caused by rust, which stopped the pawls moving properly. A squirt of 3-in-1 fixed them. Are your pawls damaged.

 

[barod]

I haven't had any problems with my Q128C, but I know other cassette motors gave the problem you described. In them, it was caused by rust, which stopped the pawls moving properly. A squirt of 3-in-1 fixed them. Are your pawls damaged.

The original problem was the freehub seizing briefly (so that it didn't coast properly), which I think is an issue that others have had. A bit of TLC and that was rectified for a while at least. However a couple of weeks ago it went the other way and lost all drive - the pedals were spinning madly, but the hub wasn't engaging. My LBS mechanic gave it a good servicing (see pictures of the state it was in when he did so), but it's wearing out and needs replacement - for example the bearing race isn't in a very good state. Pawls can be replaced, but i'm told they're not all the same (as with so much in the bike industry), so it can be trial and error to find some that would be OK.
I've sent a message to Aikema to see whether they can supply a freehub on its own, but I've also spotted this on greenbikekit, which looks remarkably similar:

bafang fatbike rm g06 motor/sondors cover with cassette base for replacement-Greenbikekit.com BBS, ebike batteries, Bafang M620, Bafang M600, Bafang M500, Bafang M510, KT controller with display-GreenBikeKit.com

Bafang fatbike rm g06 motor cover for replacement. The cassette base is included.

www.greenbikekit.com

I might give that a go - it would be cheaper than buying a whole new motor.

 

[wheeliepete]

TBK state they can order parts for the AKM motors.

AKM-128CST 48V500W Rear Driving Hub Motor Cassette motor For ebike [AKM 128CST 48V500W motor] - $118.75 : Zen Cart!, The Art of E-commerce

Zen Cart! AKM-128CST 48V500W Rear Driving Hub Motor Cassette motor For ebike [AKM 128CST 48V500W motor] - ★★★★★ AKM-128CST 48V500W Rear Driving Hub Motor Cassette motor For ebike Specification: 1. Voltage: 48V. 2. Brake type: V-brake, rim brake and disc brake are compatible 3. Connector...

www.topbikekit.com

 

[Nealh]

AKM 128 cst is cheaper at TOPBIKEKIT and they list 3 windings 201, 260 & 328.

 

[vfr400]

Did you see all their LCDs too. I can feel an order coming on!

 

[Nealh]

Yes I did, the lcd4 might appeal for a less cluttered cockpit though for me I like to have my voltage and watts viewable. Also that dinky 2.1kg cst hub with int sinewave controller, a bit pricey though at $299 + $$$ extra for lcd option. 210, 225 & 250rpm versions.

These guys have really upped their game of late and sure look better then BMSB now.