Thorn Cycles Forum

Community => Rohloff Internal Hub Gears => Topic started by: onebikeoneworld on July 31, 2017, 03:37:15 pm

Title: Drain screw query
Post by: onebikeoneworld on July 31, 2017, 03:37:15 pm
I was doing my oil change and noticed that the drain screw that Rohloff installed when they fixed my hub was different than the one for sale. It definitely seemed like it was in tighter than my regular screws do. It's the one on the left, and the new one is on the right. Anyone else have this experience?

Title: Re: Drain screw query
Post by: Danneaux on July 31, 2017, 04:14:05 pm
My drain screws (as supplied with Rohloff's oil change kits) have generally resembled the example on the right in your photo, though there have been some small variations between them.

In each case, the threads went all the way to the top and there was some "cupping" of the top surface (meaning it was concave to a degree). The variations in mine all appeared to be normal production variations.

Best,

Dan.
Title: Re: Drain screw query
Post by: geocycle on July 31, 2017, 06:38:27 pm
There's a post somewhere on here where Dave explains that the new version of drain screws have a lip on them to prevent over insertion. I just had some work done and it came back with one of the new ones.
Title: Re: Drain screw query
Post by: onebikeoneworld on July 31, 2017, 06:54:20 pm
There's a post somewhere on here where Dave explains that the new version of drain screws have a lip on them to prevent over insertion. I just had some work done and it came back with one of the new ones.

Makes perfect sense. Thank you!
Title: Re: Drain screw query
Post by: rualexander on July 31, 2017, 07:36:10 pm
Just ordered a new one from SJSC last week for my oil change, and I seem to have got the new style.
Title: Re: Drain screw query
Post by: mickeg on July 31, 2017, 09:45:29 pm
Recently Dave posted a photo of what happens if you over-tighten the screw. 
http://thorncyclesforum.co.uk/index.php?topic=1441.60

Maybe this was custom designed to try to prevent that from happening.

Title: Re: Drain screw query
Post by: Dave Whittle Thorn Workshop on August 07, 2017, 09:54:29 am
Yes Rohloff designed these so you can't over tighten them into the hub, the thread comes to a stop.

Under the old saying "make things idiot proof you just breed a better class of idiot" I've already had one back where someone managed to tighten it so much it broke the stop off the screw!