"Silent Ring" Removal?

[Beave]

Hi Dave,

I work at a large construction company here in the states. I'm in the tool and die shop and we make all our own fixturing and jigs for mass production of weldments, cnc machined parts and assembly processes. My particular duties vary greatly from day to day, but usually include machining, CAD drafting and designing, welding, troubleshooting, and pneumatic/hydraulic plumbing/troubleshooting.

My friends car situation fizzled out. He ended up fixing it himself and had no interest in coming over to watch me take apart a bicycle hub. (By the way, it was a bad bearing in his power steering pump).

So this left me with plenty of time to mess with my hub. Here are the highlights:
-My hub changed overnight. Now it appears all coasting is handled outside of ring gear 1 and 2. Planet carrier 2 walks the planets around a stationary sun gear 3, and also a rotating ring gear 3. Whatever.  Bottom line is that when coasting, the hub does what it feels like doing at any given time.
-When they say "Don't worry about accidentally draining all your oil" they are right. Even after draining overnight the hub was very slippery and was more or less falling apart as I removed gear sets from the axle shaft. Plenty of places for oil to hide until your next scheduled refill.

[Beave]

-With the bike in a stand, and the stripped hub mounted, I used a strap wrench attached to the planet carrier to make some "momemtum" and really see what happens when coasting. Like I said earlier, the hub seemed to change overnight. This test was satisfactory, but I wanted to get some real momemtum going so I.......
-Machined a simple pulley and drilled a hole through the center so I could attach my drill for a powerplant. I ran a narrow automotive belt around the hub and around the drill pulley and was able to drive the planet carrier up to a very healthy speed w/o interfering with other gearsets. This was fun.
-Prior to beginning the REAL disassembly of the hub, I noticed that I could slightly move (tilting, pushing and pulling) the ring gears and such around the axle. This play seemed to be worse after removing the silent ring and reassembling the hub.
-I had a heck of a time getting the very last sun gear to mate with the other gears when reassembling. I screwed up somewhere, somehow, but was able to remove the pin that holds the planet gear, align it to mate, then reinstall the pin.
-I put the hub back on the bike and didn't notice much change of noise in any particular gear.
I'll do some more tests tomorrow, but at this point it seems like the silent ring should probably be put back in.

[Beave]

I'd like to post pics, but a slideshow will have to do.
http://www.flickr.com/photos/climbercraig66/sets/72157625035769545/show/

[expr]

Beave,

That looks great, good job pal. The set up for the hub is fantastic good idea with the drill.

Your job sounds like mine " doing something different every day!!!! I am currently making a trace fluid injection system for buried cable identification, this injects a trace fluid in an oil Carrier which then surrounds and makes up the insulation in large underground cables, this type of cable can be seen from the road using sensing equipment that locates the exact position of cables etc instead of the old digging up method.
Tommorrow I will probably be cleaning the toilets !!!


The sun gear in the last planetary takes some mastering as you say, but once you learn how to set the planets in the correct alignment it's a lot easier. Practice makes perfect.

I found it much easier dropping the sun gear down in to the planets after setting the index marks up. I will try and show a pic giving a little more information.

If you look at the pic this shows the right planet you will see 5 teeth exposed on the aperture where the sun wheel would be, the pencil is pointing to the correct position for this planet, the first and 5th teeth are half exposed so correct position for this planet is 1.5 teeth up from the bottom, the mirror image has to be perforemed on the left planet 1.5 teeth up from bottom and the top tooth should be in the center. If you set the planets up like this it should fit first time. It helps to marker pen the indexed tooth for better verification.

[Beave]

Thanks Dave. Yeah I forgot the step of marking the teeth, and then came to find out that none of them had been marked during manufacture. I've seen a few different tear downs, with timing marks ranging from permanent marker to what looks like a center punch indentation. Not sure if those are all homemade or done by Rohloff. Anyway, yes marking them prior to removal certainly must be better than the route I took.

And to clarify, although there are many different "routes" for freewheeling to find a neutral output, the picture below I believe indicates the most common scenario and was more or less proven by my drill/belt drive test. And, there was absolutely no variation in the observation, from gear 1 to gear 14. One thing I did notice, is that as speed increases, more and more gears start to "come along for the ride" and get pulled into the rotation, albeit markedly slowler.

Freewheel Explo by climbercraig66, on Flickr

[Beave]

You Tube Videos (All taken prior to silent ring removal)

Setup and powering the hub
http://www.youtube.com/watch?v=FGnGbsA9OJI

Viewing Perpendicular to the axle
http://www.youtube.com/watch?v=ZK7eZcSEouY

Just listening to high range / low range gear noises (shifting 7 to 8, 8 to 7) Low range being the noisiest.
http://www.youtube.com/watch?v=7kdppHAOmUQ

[expr]

Beave, the videos are great good job. I see what you mean about the gears coming along for the ride looks like frictional drag is taking place there.

Not to sure about the index marks, look very carfully for them they should be a very small indent like a center punch mark, its only small but should be there. I would then use a marker just to highlight the indexed tooth.

very curious also going back to the original question of silent ring removal as to the lack of change in noise, I defiantly think its dimension critical , as you suggested the inherent amount of free movement without it installed. I know a couple of people at rohloff so I'm going to try and ask for there opinion as to the main purpose of it.

[Beave]

Hey Dave,

Yeah, I found the index marks today. I installed a better light over my workbench. You are right, they are very hard to see.

That would be great if you could talk to your friends at Rohloff. I guess you could have mentioned that prior to me getting into this  Just kidding. I of course enjoyed every minute of it.

And just to wrap this up, I put the silent ring back in and the hub definitely does have less side to side slop. But yeah, from what I could tell, "silent ring", like you said earlier, seems to have more to do with the qualities of the ring than the actual purpose, despite the misleading factory tour video I was referring to.

Speaking of videos, I did a dismantle and reassemble video and am posting it to Youtube right now. I didn't have time to get into the axle itself (15 minute upload limit on Youtube), but figure most will enjoy the videos anyway.

I'll post them to a new thread after they are uploaded.
Thanks for hanging with me on the topic!