My first crisis.....!

[Kwozzymodo]

So, I spent the morning lacing my q100c cst hub into a rim. No problems. However, when I put the wheel into the bike frame, it has seized up and won’t move forward or backward. At first I thought that the disc brake caliper needed adjustment... No, all good there, with plenty of clearance. I took the wheel out of the frame and put it back in my truing stand to take a look...., the wheel was very difficult to turn around the axle (the axle was absolutely free when I was lacing/truing the wheel). I plugged the motor into another bike and the wheel turns okay under power. I have put the wheel back in the bike frame and it is locked up completely. The cassette turns backwards fine, so no problem with the freehub body.

So, what has happened? Do I need to take the thing apart and hit something with a hammer, is is the hub just kaput? Or am I doing something really stupid.......

 

[DynatechFan]

Curious - and very frustrating no doubt. If it was a "normal" hub then the cones might be a culprit but these hubs are sealed bearing?

 

[flecc]

Spindle nut on the left side of th motor overtightened against the sealed bearing possibly, seizing it. Hold the spindle still, undo that nut a little, then do it back up to take up all the slack but not tightening it hard against the bearing.
.

 

[Kwozzymodo]

They are....

I can turn the motor on the axle one way and it goes around three-quarters of a turn before locking up. I can then turn the axle backwards for three-quarters of a turn before locks up and it feels like I am turning against a ratchet or gear whilst I turn it backwards. I have loosened the nut and locknut holding the freehub body.

I am thinking something has gone pop with the internal gearing, but I don't understand why.....

 

[Nealh]

It sounds like the clutch mechanism inside, there are 3 small pins and springs. You have to unscrew the hub and check they are aligned/installed correctly. The hard part is making a tool to open the casing, being new it shouldn't be to difficult.

 

[D C]

Are the bolts holding the disc slightly long and catching?
Dave.

 

[Nealh]

Are the bolts holding the disc slightly long and catching?
Dave.

Good call, worth a check before opening hub up.

 

[Kwozzymodo]

Update: I think you might be right regarding the disc bolts. Everything was turning freely until I installed the disc. So, with the disc bolts removed, I can turn the axle both ways. However, turning it one way has more resistance and it feels like cogs are engaging. When I take the three screws off the motor casing, the axle turns freely both ways.

So, it feels like I have knocked something out of alignment by tightening the disc bolts. Neal mentioned the clutch plate and this may well be the issue?

Is there an online guide to dismantling the q100. I feel like a novice doing brain surgery here......

 

[Deleted member 4366]

Firstly, normal bicycle disc screws are too long. You must use the crappy ones that came with the motor.

The clutch and gears are on the opposite side of the motor, so you can't damage them with the disc screws. On the other side, there's a steel axle flange and thick aluminium, so I'd be surprised if you've done any serious damage. Most likely the longest screw was catching on the trough for the wires or the screws for the hall sensor board..

It's normal for there to be resistance in one direction because the clutch engages when you turn the motor backwards and the high reduction ratio means that the motor's rotor is turned quite fast.

 

[Planemo]

You do need to be careful with disc bolts on all motors. Every disc bolt I have come across is far longer than the ones which were supplied with my oxydrive kit which is why I have kept using them despite getting shiny new ones with the couple of new discs I have bought. My concern is that you could have screwed them into some windings or something. I am not sure what is directly behind the bolt threads but it is probably quite important. You might be lucky, just take the disc off, fit the wheel and tentatively try connecting power. Keep all fingers and toes crossed and see if it spins up ok.

 

[Planemo]

Crossed posts with d8veh...he's the man...looks like you should be ok given that its just a flange behind the bolts and not some wiring/gears etc.

 

[Kwozzymodo]

Thanks for the responses. When I was truing the wheel, I noticed very little resistance spinning it either way. Now, it spins freely around the axle when turned forwards, and is super stiff going backwards, to the point I need a 10mm spanner to hold the axle whilst turning the wheel. Something is definitely binding somewhere. Any ideas?

 

[Deleted member 4366]

That's normal, but "super stiff" is not quantified. Clamp the axle in the drop-outs, the wheel should rotate a couple of times if you spin it by hand backwards. Forwards, it should be pretty free.

 

[Kwozzymodo]

Good point! It’s fine forwards. Doesn’t spin at all backwards.

 

[Kwozzymodo]

All sorted. I popped the motor open and took the clutch apart. Reinstalled everything and the wheel spins fine, both ways. All hooked up and working. Thanks for the replies.