anga

Hello,

Hubs: any 8-speed Shimano IGH, preferably SG-8R36, SG-S501

See attached figure.

Can you measure the diameter or circumference of the NDS & DS openings? Can live with an error of a couple of mm. Please indicate hub model, too.

Thanks.

Andrew R Stewart 

What ya planning? Maybe a stub type axle? Trike? Andy (who has a SA AG hub on his bench right now)

anga

I wish. Not even close.
Need to find max size of outside calipers that can fit either end of the hub.
Just discovered hub shells are not available as spare parts and want to be careful locating oil ports. Outside calipers are less expensive than vernier calipers.

Bill Kapaun

Vernier is a type of measurement which works wonderfully in the decimal system.
They can be inside or outside.

anga

The outside calipers I am considering doesn't have a scale. Hence the lower cost. Top two in figure.

Bill Kapaun

No idea why you would mention Vernier then.
https://en.wikipedia.org/wiki/Vernier_scale
https://www.harborfreight.com/6-in-u...per-63664.html

anga

In my reply to Andrew, I said
"Outside calipers are less expensive than vernier calipers."
Perhaps I was too cryptic.
I meant outside calipers, without scale, are less expensive than vernier calipers (the usual calipers that look like a ruler).

I just needed to find a suitable point inside the shell and the corresponding point outside the shell.

Bill Kapaun

I was trying to educate you.
Lost cause
Ignore list

anga

Known about and used vernier calipers for 40+ years. Not sure I need to be re-educated.
Thanks for trying, though

grumpus

You can measure it from your photo, given that the PCD of the spoke holes is 89.4 mm.

anga

That is a brilliant idea. So obvious and yet so hard to see.
Wish I had thought of it.
Thank you, so much.

For Alfine and Nexus 8-speed hubs, google shows around 92.6 to 93mm as PCD.
https://www.sheldonbrown.com/nexus8/pages/28.htm
https://www.kstoerz.com/freespoke/hub/168
https://www.kstoerz.com/freespoke/hub/169

Hub in photo (not mine) is Alfine SG-S500 or 501.

grumpus

Whoops, for some reason I quoted a Sturmey Archer dimension - I was probably trying to do two things at once.

anga

From the photo,

NDS opening is between 75 and 80mm
DS opening is between 16 and 18mm.

Accuracy is limited by the presence of grease and probably recessed DS opening.

Appreciate any physical measurements. No need to remove hub from wheel or wheel from cycle.
Use a pair of dividers for diameter or a string and scotch tape for circumference.

hevysrf

I'm also interested in oil port for my nexus hub, post some photos when you're finished, thanks , Marty

Dan Burkhart 

One thing to be aware of is to take care to drill into the shell in a location that doesn’t hit the roller clutch drive track that is roughly in the middle.
Also important to do it with the internal assembly removed because even minuscule chips from the drilling process will play havoc with the internals.

sweeks

Let me play the Devil's Advocate here.
The Nexus hubs are not sealed well enough to be filled with a substantial amount of oil, as (for example) the Alfine-11 is. There may not be a way for the oil added through a port to reach the non-drive-side bearing.
It's very easy to pop the gear cluster out of the hub once a year to dip in gear oil. This provides the opportunity to properly grease the bearings, as well as to inspect the mechanism for any developing problems.
(/DA Mode)

anga

Why not post the measurements first?

hevysrf

My father was a machinist with navy training, when he saw how I handled a micrometer, he told me I would be better off as a plumber. He wasn't far off.

anga

Hate to say this.

If you cannot use a divider + ruler or a digital calipers to measure diameter or measure circumference with string + tape, you shouldn't even think of an oil port.
Search this forum + internet for photos.