A customer dropped off a WH-7701 with me.
They wanted a hub overhaul and truing work.
Currently cleaning...
Cup and cone hubs often show different wear patterns on the left and right ball bearings,
so I need to keep track of which cone, balls, and adjusting cone belong to which side
before and after the work. In this hub's case, both sides use loose balls,
so I'm being especially careful to keep them from mixing together.
In the previous image, the balls that remained in the hub are on the left side of this image,
and the ones I dropped into the tray are on the right side.
The left side has a slightly duller color, but it's hard to tell from the photo.
They weren't in bad enough condition to replace, so I reused them.
This hub has 11 balls on both sides, but you only see 10 on the left in this image
because one was still in the cleaning container at the time the photo was taken.
There was slight center offset, but I fixed it before taking the photo.
The WH-7700 and WH-7701 have hub internals equivalent to 7700-series Dura-Ace hubs,
with stepless bearing adjustment using a hub wrench to tighten the W-nut.
With the 7900-series and later digital ratchet systems,
you can't get to that sweet spot where adjustments are infinitely fine without play,
but if you know the technique, anyone who works on it gets the same result—
superior in terms of maintainability.
The 7800-series hubs also use W-nut stepless adjustment, but for some reason
they can't achieve that almost supernatural smooth, light rotation like the 7700 hubs do.
They're smooth, but only deliver a sluggish, dull feel to the rotation.
With the 7800 rear hub, the ratchet mechanism isn't the traditional Shimano type
but a pole spring design like Campagnolo's freewheel body, and this might be
the reason for the difference.
The front hub has a larger diameter hub shaft than the 7700, but the ball bearing size
is the same 3/16 inch as the 7700
(early models used loose balls with 14 per side, later models used bearing retainers).
This is just my theory, but I suspect the contact between the balls and the cones and adjusting cones
has shifted from point contact to slightly surface contact.
As a result, I have several 7700 hubs lying around in my workshop,
and not a single 7800 hub—that's why.
Especially the front hub; I still use it on a bike.
At the final spoke cross, there's a spoke spacer wedged in
to prevent spoke creaking, but
The front and rear wheels of the 7700 and the front wheel of the 7701
use JIS lacing for the final cross. The reason is:
if you use Italian lacing instead, the final cross on the opposite side
would need a spacer with the slit oriented the opposite way.
If the final cross angle were around 90°,
Italian lacing with shared spacers on both sides might work, but...
Now for the rear wheel.
The WH-7701 rear wheel, unlike the WH-7700,
uses radial lacing on the freewheel side, and
the hub flange is also wider.
As long as they don't whimsically make the flange width wider or narrower from this point on,
I won't call them out for "wide flange fraud" (→here).
This uses a kinked spoke design with the kink on the rim side,
hooked to the rim via a spoke washer.
The dimensions of the kinked section are quite different from standard spokes,
so you can't do things like patch a spoke section with something like CX-RAY.
Besides, these spokes were discontinued long ago.
The point I'm making is: once one spoke breaks,
the wheel is done.
My attempts to patch it with standard spokes have repeatedly failed
(it looks like it should work, but it doesn't).
I loosened the double nut on the non-freewheel side and pushed the hub shaft toward the freewheel side.
Despite appearances, the seals are doing their job properly,
and sand-sized debris hasn't entered the hub interior.
Cleaning in progress...
I might not have needed to remove the freewheel body.
The hollow bolt that fixes the freewheel body to the hub shell—
on 7700-series hubs it's steel.
On 7800-series, it's Campagnolo-style, so it's not this type.
On 7900-series it becomes an aluminum hollow bolt, but
the usage count is one: when you reinstall the freewheel body,
you must always replace it with a new one—that's the manufacturer's directive.
I checked the spare parts just now and it's been discontinued!
I have actuallyreused it many times,
and I've never had a problem from it.
No center offset; same result even after slight lateral truing.
This wheel is something I'll need for a story I'm planning to write later,
but I don't need to take photos for that right now.
Because I already have one in my personal collection.
They wanted a hub overhaul and truing work.
Currently cleaning...
Cup and cone hubs often show different wear patterns on the left and right ball bearings,
so I need to keep track of which cone, balls, and adjusting cone belong to which side
before and after the work. In this hub's case, both sides use loose balls,
so I'm being especially careful to keep them from mixing together.
In the previous image, the balls that remained in the hub are on the left side of this image,
and the ones I dropped into the tray are on the right side.
The left side has a slightly duller color, but it's hard to tell from the photo.
They weren't in bad enough condition to replace, so I reused them.
This hub has 11 balls on both sides, but you only see 10 on the left in this image
because one was still in the cleaning container at the time the photo was taken.
There was slight center offset, but I fixed it before taking the photo.
The WH-7700 and WH-7701 have hub internals equivalent to 7700-series Dura-Ace hubs,
with stepless bearing adjustment using a hub wrench to tighten the W-nut.
With the 7900-series and later digital ratchet systems,
you can't get to that sweet spot where adjustments are infinitely fine without play,
but if you know the technique, anyone who works on it gets the same result—
superior in terms of maintainability.
The 7800-series hubs also use W-nut stepless adjustment, but for some reason
they can't achieve that almost supernatural smooth, light rotation like the 7700 hubs do.
They're smooth, but only deliver a sluggish, dull feel to the rotation.
With the 7800 rear hub, the ratchet mechanism isn't the traditional Shimano type
but a pole spring design like Campagnolo's freewheel body, and this might be
the reason for the difference.
The front hub has a larger diameter hub shaft than the 7700, but the ball bearing size
is the same 3/16 inch as the 7700
(early models used loose balls with 14 per side, later models used bearing retainers).
This is just my theory, but I suspect the contact between the balls and the cones and adjusting cones
has shifted from point contact to slightly surface contact.
As a result, I have several 7700 hubs lying around in my workshop,
and not a single 7800 hub—that's why.
Especially the front hub; I still use it on a bike.
At the final spoke cross, there's a spoke spacer wedged in
to prevent spoke creaking, but
The front and rear wheels of the 7700 and the front wheel of the 7701
use JIS lacing for the final cross. The reason is:
if you use Italian lacing instead, the final cross on the opposite side
would need a spacer with the slit oriented the opposite way.
If the final cross angle were around 90°,
Italian lacing with shared spacers on both sides might work, but...
Now for the rear wheel.
The WH-7701 rear wheel, unlike the WH-7700,
uses radial lacing on the freewheel side, and
the hub flange is also wider.
As long as they don't whimsically make the flange width wider or narrower from this point on,
I won't call them out for "wide flange fraud" (→here).
This uses a kinked spoke design with the kink on the rim side,
hooked to the rim via a spoke washer.
The dimensions of the kinked section are quite different from standard spokes,
so you can't do things like patch a spoke section with something like CX-RAY.
Besides, these spokes were discontinued long ago.
The point I'm making is: once one spoke breaks,
the wheel is done.
My attempts to patch it with standard spokes have repeatedly failed
(it looks like it should work, but it doesn't).
I loosened the double nut on the non-freewheel side and pushed the hub shaft toward the freewheel side.
Despite appearances, the seals are doing their job properly,
and sand-sized debris hasn't entered the hub interior.
Cleaning in progress...
I might not have needed to remove the freewheel body.
The hollow bolt that fixes the freewheel body to the hub shell—
on 7700-series hubs it's steel.
On 7800-series, it's Campagnolo-style, so it's not this type.
On 7900-series it becomes an aluminum hollow bolt, but
the usage count is one: when you reinstall the freewheel body,
you must always replace it with a new one—that's the manufacturer's directive.
I checked the spare parts just now and it's been discontinued!
I have actually
and I've never had a problem from it.
No center offset; same result even after slight lateral truing.
This wheel is something I'll need for a story I'm planning to write later,
but I don't need to take photos for that right now.
Because I already have one in my personal collection.