Another day of wheel building (and so on).
A customer entrusted me with a 7800 rear hub.
They purchased it used and requested an overhaul,
but since they bought it from a private individual rather than a shop,
it simply means they're not the first owner.
There are no spoke lacing marks on the flanges, and no traces of sprocket installation on the freebody.
It's essentially new, but aside from what the customer requested,
I had no choice but to grease it up (more on this later).
Grease and oil sometimes drip out like runny nose from the gaps in the hub body and clog the flange holes (see image above),
but this happens regularly even with the Evo Lite hubs I usually use,
so I actually give them a quick wash before building wheels.
The rim is a Tni AL27 or AL300,
32H hub with 48-spoke lacing and radial spoking on one side,
and for spokes they want Strong/Competition or Champion/CX-RAY
with maximum left-right diameter variation—basically "my idea of the ultimate wheel" spec.
The flange holes on 7800/7900/9000-series Dura-Ace hubs won't accept Strong #13 spokes.
I believe this is to reduce the risk of spoke breakage at the neck for #15-base spokes.
When you order a hub from my mentor figure, if you're using #15-base spokes,
they'll drill flange holes that won't accept #14 spokes.
Their hubs are mostly used on small-wheel bikes, and since #15 plain spokes are common on small-wheelers,
those considerations become more important than they would be for 700C wheels.
This is specific to Dura-Ace; hubs of the same generation in Ultegra and lower grades
pass #13 spokes fairly easily.
With Chris King hubs, Strong is quite difficult to thread through, though it is possible.
So the flange hole diameter is somewhere between Ultegra-and-below and Dura-Ace-and-above.
↑Outside flange is #13, inside is #14
So I decided on Champion for the freewheel side and CX-RAY for the non-freewheel side.
What you might call a semi-Champion build.
↑Campagnolo knockoff
The bearing adjustment had no play, but there was a slight scratching sensation in the rotation.
Ah, so this is an early-type A model.
7800 hubs come in two types: A-type with loose ball bearings and B-type with retainer bearings.
With loose balls, the steel spheres clatter against each other during rotation,
but unless the grease is completely depleted, it won't produce a noticeable sensation.
When I removed the left cone, the steel balls tumbled down into the hub body.
You could prevent this by creating a lip on the inside of the cone or on the hub axle,
making the gap smaller than the ball diameter,
(or by using retainer bearings),
but this hub doesn't have that.
You can assemble it by using grease to hold the balls in the cone
and fitting the cone straight on,
but assembly in a completely degreased state is extremely difficult.
There's no reason to go through that trouble anyway.
This is why I had to grease it up regardless of what the customer wanted.
By the way, I packed it with significantly more grease than what's shown in the image,
so unless you keep riding with play in the hub,
it should be virtually maintenance-free for all practical purposes.
Like Shimano's complete wheels, with Dura-Ace-grade hubs,
the rim's lifespan comes first.
It's built.
Feh heh heh. Third win today.
FH-7800 32H semi-Champion 48-spoke lacing with radial spoking on one side.
It's extremely stiff, but are you really sure about this?
The non-freewheel-side flange diameter isn't extremely small, so
with 32H 8-spoke lacing, the overlap of the radial spoke head over the non-radial one is modest.
By the way, spoke replacement is possible.At least for me, anyway.
The nipples are aluminum, not brass.
If you're confident you won't strip the nipple's grip surface before finishing the wheel build,
or if you have the setup to prevent it,
there's no reason to use brass nipples.
The exception is carbon rims, where friction with the nipple is extremely high.
Recently, those carbon rims from Niseki with slightly different rear-rim specs from the front,
I built those with brass nipples.
A customer entrusted me with a 7800 rear hub.
They purchased it used and requested an overhaul,
but since they bought it from a private individual rather than a shop,
it simply means they're not the first owner.
There are no spoke lacing marks on the flanges, and no traces of sprocket installation on the freebody.
It's essentially new, but aside from what the customer requested,
I had no choice but to grease it up (more on this later).
Grease and oil sometimes drip out like runny nose from the gaps in the hub body and clog the flange holes (see image above),
but this happens regularly even with the Evo Lite hubs I usually use,
so I actually give them a quick wash before building wheels.
The rim is a Tni AL27 or AL300,
32H hub with 48-spoke lacing and radial spoking on one side,
and for spokes they want Strong/Competition or Champion/CX-RAY
with maximum left-right diameter variation—basically "my idea of the ultimate wheel" spec.
The flange holes on 7800/7900/9000-series Dura-Ace hubs won't accept Strong #13 spokes.
I believe this is to reduce the risk of spoke breakage at the neck for #15-base spokes.
When you order a hub from my mentor figure, if you're using #15-base spokes,
they'll drill flange holes that won't accept #14 spokes.
Their hubs are mostly used on small-wheel bikes, and since #15 plain spokes are common on small-wheelers,
those considerations become more important than they would be for 700C wheels.
This is specific to Dura-Ace; hubs of the same generation in Ultegra and lower grades
pass #13 spokes fairly easily.
With Chris King hubs, Strong is quite difficult to thread through, though it is possible.
So the flange hole diameter is somewhere between Ultegra-and-below and Dura-Ace-and-above.
↑Outside flange is #13, inside is #14
So I decided on Champion for the freewheel side and CX-RAY for the non-freewheel side.
What you might call a semi-Champion build.
The bearing adjustment had no play, but there was a slight scratching sensation in the rotation.
Ah, so this is an early-type A model.
7800 hubs come in two types: A-type with loose ball bearings and B-type with retainer bearings.
With loose balls, the steel spheres clatter against each other during rotation,
but unless the grease is completely depleted, it won't produce a noticeable sensation.
When I removed the left cone, the steel balls tumbled down into the hub body.
You could prevent this by creating a lip on the inside of the cone or on the hub axle,
making the gap smaller than the ball diameter,
(or by using retainer bearings),
but this hub doesn't have that.
You can assemble it by using grease to hold the balls in the cone
and fitting the cone straight on,
but assembly in a completely degreased state is extremely difficult.
There's no reason to go through that trouble anyway.
This is why I had to grease it up regardless of what the customer wanted.
By the way, I packed it with significantly more grease than what's shown in the image,
so unless you keep riding with play in the hub,
it should be virtually maintenance-free for all practical purposes.
Like Shimano's complete wheels, with Dura-Ace-grade hubs,
the rim's lifespan comes first.
It's built.
Feh heh heh. Third win today.
FH-7800 32H semi-Champion 48-spoke lacing with radial spoking on one side.
It's extremely stiff, but are you really sure about this?
The non-freewheel-side flange diameter isn't extremely small, so
with 32H 8-spoke lacing, the overlap of the radial spoke head over the non-radial one is modest.
By the way, spoke replacement is possible.
The nipples are aluminum, not brass.
If you're confident you won't strip the nipple's grip surface before finishing the wheel build,
or if you have the setup to prevent it,
there's no reason to use brass nipples.
The exception is carbon rims, where friction with the nipple is extremely high.
Recently, those carbon rims from Niseki with slightly different rear-rim specs from the front,
I built those with brass nipples.