FREEWHEEL PROBLEM

Joined
Oct 6, 2012
Messages
2,078
Location
SF Bay Area
I recently bought a hub motor MAC 6 T , then bought a Sunrace MFEX9 9 speed freewheel,

I did not have a freewheel remover tool, so I put the freewheel on hand tight, but noticed it needed a little more torque,
so I got my chain whip tool ( sprocket Remover Tool ) and tightened (clockwise ) the freewheel on a little more
after that I tried to turn the freewheel ... counterclockwise, to see it working but it does not turn counterclockwise, ?

I looked to check the spacing between the freewheel and the hub, and there is plenty, 4-5 mm no issues there.
Hub not laced up to a rim yet so no issue there either .

What is going on ?

So then I went to a couple of bike shops to find a freewheel remover tool, and bought one, ( Park Tool FR-1.2 for Sunrace/Shimano/Sacs )
got it home only to find out that the hole in the middle of the remover tool is too small for the axle of a electric hub motor .
they are made for axles that are up to 10 mm O.D. and the MAC electric hub motor axle is 14mm O.D.
I will try to drill the hole bigger , although I called Park Tool and they say the tool is hardened steel, so have not done that yet.
I put in a request to the tec worker at Park Tool and he said that the company does know about this problem, they just don't make a freewheel remover tool for the larger axle's , yet. Who Does ?
 
Wish I saw that a couple of weeks ago, ( http://www.ebikes.ca/fwtool.html )
However, since I already have bought the Park Tool FR-1.2 from a local bike shop
and It would take over a week to get one from ebikes.ca I just got back from a local
Machine Shop, who boored out the hole for me to 5/8" . ( 15.88 mm ) to be on the safe side. :)

Now that I have taken off the freewheel, and put it back on a few times, I have found the same problem when I tighten it up, ( will not freewheel ) even when I tighten loosely, even tighten only as much as a
persons torque on the cranks, would tighten it, ... it now it still does , Not , freewheel !

Looks like I will need a spacer behind the freewheel, ( between the back of the freewheel and the hub ) which will create another Problem ...

Since the Mfg's of hub motors, like the MAC, make the hub too wide, they want you to use a 7 speed freewheel, the 9 speed freewheel is wider, and I will now need an even wider spacer on the Axle , to , bend out the drive side Seatstay/Chainstay/Dropout

When are the Hub Motor Mfg's going to make the hubs a little thinner, Most every bike now is at least 9 speed, Many are 10 speed, and the new 2015 bikes in the bike shops are 11 speed !
The Hub Motor Mfg's really need to get this done like, NOW , before we all go to mid - drives !
 
It's often not the width of the hubmotor, but where they put it on the axle. Since it's usually centered on the axle (which a normal rear hub may not be, because it leaves space for that gear cluster), ther'es "wasted" space to it's left that could've been "moved" to the right side for the gear cluster, by putting the axle shoulders offset.

Then the hubmotor would just need to be dished like a normal hub would be, for the rear, and it would work the same way as a normal hub for the cluster too.


But with many hubmotors they're so large in diameter that it's not possible to dish them enough to get the rim centered, or else it leaves the wheel weaker (too weak, sometimes).

To fix *that* problem, they'd need to widen the flanges, which would increase materials costs and make the motor heavier, whcih may be reasons they don't do it.

So...we end up with what we have now. There *are* some hubs that don't have these issues, but most of the ones I've seen do.
 
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