Difficulty in dismantling ebike front hub motor

[Peter Brigg]

This motor (Pictured) is giving me a heap of trouble trying to get it apart. The supplier BMS Battery has not answered my email and I have not been able to locate parts diagram.
Has someone successfuly taken one of these apart ModelQ100 350w Thanks Peter

 

[chuyskywalker]

Looks like a general geared hub motor. Unscrew the nuts to drop it from the fork, then there are usually just some bolts on the side (likely behind the disc) that, when removed, will allow you to take the core out.

You can probably youtube up some examples with the keywords above.

 

[AGS]

I believe the side cover is threaded and you will need to fabricate a tool to use the three screw holes to unscrew it. There are some YouTube videos floating around of how to do this.

 

[docw009]

I also have a Q100H that I want to take apart, Have not done that yet, but I did collect some pics/advice from this forum.

Google for "Q100 Motor disassembly," This thread comes up. Thare are lots more.

Hub motor maintanance (q100, q85)

The cover screws on, left hand thread, You'll need to make a tool to turn it.

 

[chuyskywalker]

The cover screws on, left hand thread, You'll need to make a tool to turn it.

boy howdy I was wrong in my reply. Bit of a pain, that one

 

[Peter Brigg]

Thanks for that information-problem solved. I would never have thought that it came apart as a threaded component-in many ways a very cleverly put together piece of equipment. My reason for wanting to pull it apart was that occasionally when riding the bike the motor seemed to grab-making what sounded like something was badly wrong. I managed to get some silicone spray into the assembly and that stopped the noise(for a while) so perhaps the noise is a result of poor lubrication

 

[Papa]

My reason for wanting to pull it apart was that occasionally when riding the bike the motor seemed to grab-making what sounded like something was badly wrong. I managed to get some silicone spray into the assembly and that stopped the noise(for a while) so perhaps the noise is a result of poor lubrication

One weak point in the Q100 is the one-way sprag clutch. The roller (3 ea. IIRC) return spring gets snagged under the roller causing the clutch to slip or fail to lock completely. See similar arrangement below:



Also: Don't use a liquid lubricant - lightweight grease only for the gears. There is no axle seals and liquid lube will leak onto the brake rotor, resulting in brake failure.

 

[Peter Brigg]

Thanks for that comment Papa-appreciated. I bought 2 of these motors and unfortunately when dismantling I used screws that were too long and they went through the component and damaged the clutch ( on one of the motors) For other readers please use screws that go no deeper than the original screws supplied on the motor. Live and learn. Fortunately I can use the undamaged clutch on the spare motor now but as you say the clutch is probably the most dodgy bit in the assembly. Is there any chance of buying the clutch as a spare part? Just to clarify things for me-when the motor is travelling in the direction indicated by the arrow the rollers jam and the motor pushes the bike?? When the bike is freewheelingthe rollers move a little counter the arrow and spin freely? To limit wear on the clutch perhaps pedal where possible?

 

[Papa]

It's been several years since I dissected a Q100H, although I still have two of them among my stash. One is new and unused, but laced to a rim. The other is disassembled, but I'd have to look for it (i've moved since so not sure where I put it). Anyway...

Just to clarify things for me-when the motor is travelling in the direction indicated by the arrow the rollers jam and the motor pushes the bike??

The image I posted above is NOT related to the Q100H hub,... however, the image above does show "Guide pins", which the Q100H, sadly, does NOT have. But basically, you are correct Re functionality.

The roller springs are hidden in a cavity behind the rollers, so you'll only see a few coils protruding. Look closely,... are any exposed coils 'unwrapped' and trapped beneath the rollers? If so, you'll need to replace the damaged spring(s). I went a step further - I inserted a single ball bearing between the springs and the rollers (to prevent the springs from being snagged and pinched by the rollers). The ball bearings I used were tiny headset bearings (don't remember the diameter), but a single ball fits perfectly in the cavity, between the spring and roller. The spring's overall length was trimmed to accommodate the ball bearing's diameter. Make sense?

 

[Peter Brigg]

Yes-makes sense-I have bought these from BMS battery and they are not that expensive. Fright can be expensive

 

[Papa]

More tidbits...
Mine are 328 RPM - others are 201 & 260 RPM. The gears are NOT interchangeable between them because the RPM difference is gear ratio, not windings. Also, on mine, I had to align (time) the 3 planet gears to successfully reassemble. There should be (paint?) marks on the planet's teeth to guide you. Your 201 may be different, dunno... I've not disassembled either the 201 or 260.

 

[Peter Brigg]

Now I have disassembled the motor and found 2 of the springs with a near 90 degree bend where they have been "munched"
I have thought of cutting off the smaller section of spring and stretching the remaining piece until it is the same length as the good spring then re assembling. Feasable? I may also take up your suggestion of shorter springs and ball bearings.
Previously I temporarily solved the lack of lubrication by using a silicone spray which worked for a short time however as stated the disc brake has become ineffectual. Can the silicone lubricant be cleaned off the brake pads? Cleaning the rotor is straightforward.

 

[Peter Brigg]

Just to check an observation I have made. "When the motor is used the sprag clutch locks up ie the driving force of the motor locks the rollers in their channels and the entire system is locked. When coasting the sprag clutch releases and the motor/gear system in effect disconnects" Correct?

 

[Papa]

I have thought of cutting off the smaller section of spring and stretching the remaining piece until it is the same length as the good spring then re assembling. Feasable?

I would discourage stretching the springs. Either replace w/new spring, or trim the spring and insert a ball bearing - bearing needs to be slightly larger in diameter than the spring, but closely fits the ID of the cavity. I used early 1" headset (loose, not caged) ball bearings) - your local bike shop will have them.

Can the silicone lubricant be cleaned off the brake pads?

Yes - Auto parts stores have disc brake cleaner. Acetone will also remove it.

Just to check an observation I have made. "When the motor is used the sprag clutch locks up ie the driving force of the motor locks the rollers in their channels and the entire system is locked. When coasting the sprag clutch releases and the motor/gear system in effect disconnects" Correct?

Yes.

 

[Papa]

Also - was there any paint marks on any of the plastic planet gears? If so, be careful to avoid washing it off.

 

[Peter Brigg]

Have acetone as I do a bit of fibreglass work at times. I did not fully dismantle the motor so the nylon gears remain as they were (in relation to one another)-I realised the noise was coming from lack of lubrication and was able to put some silicone grease on the gears then rotate them to spread the grease around. Did not see marks on the gears but will look carefully if ever I have to replace gears and do a full dismantle