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Discussion Starter #1
Has anyone ever had luck removing the cush drive/rear sprocket stud rubbers on an old rear hub (Honda 160 in this case)?
They probably never wear out in normal use but a couple on my race bike are extremly worn and 1 now points off center. I've been trying to remove some from an old hub as a practice exercise and can't get anything to move.
Tips???
 

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Use an Exacto knife or other such implement of destruction to cut around the rubber area. Once the center sleeve section has been extracted, use a Dremel tool or die grinder to "slice" through the side of the outer steel sleeve of the bushing.

Cheers, Bret @ Glass from the Past
 

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No. One of the worst experiences of my life...

I had the best of intentions removing those bastards. I carefully removed the rubber center, dremeled through the outer ring, soaked them with all kinds of nasty stuff and they wouldn't budge. Ended up spending about 40 hours with a hammer and chisel to get tiny little shards of cush drive out.



I patched up and smoothed the gouges in the aluminum hub with JB weld later.
 

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that all sounds bad. if i understand what i'm seeing, it looks "easy" to blow out the rubber inside the two steel sleeves at which point the outer sleeve is still stuck in the hub. If that's the case, then by applying heat to the hub thus yielding a larger (alum) hole diameter than the (steel) insert diameter. the sleeve/insert should then fall out...just like replacing bearings in a hub. if i don't understand....sorry for making you read this.
-parks
 

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Discussion Starter #5
Parks- that should work and that's what I've been doing to the "practice" hub but the years of corrosion are working against me. I definately don't want to do this but the sprocket is kind of wobbly at this point so I have to address it.
Thanks Brett,tsflstb kind of the worst case scenario but it looks like what I've got too.
 

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Yeah I think I've actually just fired up the torch and burned them out before. That gets rid of the rubber...and usually abuses the rest of it enough that the shell will come out.

If I had something like that here in the shop I'd try to either mill out the outer sleeve...or weld something to the sleeve and pull on that.

I've noticed that some rear cushes on the 175's seem to hold up forever, other seem to fall apart with very little race use. Noticed the same difference in the cam chain rollers...the soft ones tend to last a long time the hard ones desinagrate.
JohnnyB
 

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whats a cam chain roller?

<img src=icon_smile_wink.gif border=0 align=middle>


jc

i dont know shit
 

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jb, that's a trick question . . .. use the search function and you, grasshopper, may find the answer!! ) IT has something to do with . . .

I'm slow and not so evel
 

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Found it -

Slick!

I'd looked at KZ rollers but they're hella expensive.

I don't know if any of you have tried this on the cush rubbers, but once you get the rubber out if you can get it cleaned up enough to weld - and assuming you can reach in there (not for sure that small) - if you run a couple of beads around it with a wire feeder it'll shrink enough on cooling to almost fall out. Works great on steering head bearings where the lower race has no lip for removal (lots of dirt bikes for instance). Run a bead around it with the wire feed, wait for it to cool. Most of the time it'll fall out on it's own.

Michael

Michael
 

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Michael....yeah I went this route when I saw the price of those sprockets. Was worried at first at the speed this little sprocket would be turning, but doesn't appear to be a problem so far. If you try this mod you'll get a feel for what's necessary as you put it together. I try to leave a little room for oil to get to the needle bearing. Use "low head" hardware (6mm) to replace the little pressed in OEM shaft.
Still no definative word on cam chain wear....but it's not so bad that it's destroying anything quickly...been running this for two seasons so far. The machine work can be a bit tedious at first until you do a couple of them.

JohnnyB

PS. Good idea on the cush drive shells...gotta try that sometime.
 

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Two seasons is great - I'd say you've got some excellent reliability data there already.

Thanks for the tips - I'm sure it'll be relatively self-evident. For a lot of stuff like that I make my own low profile hardware - I'd assumed I'd have to do it again.

Are the sprockets hardened at the internal splining? (my machine tools are pretty small)

You'll love the welder trick if you ever need it. I use it for stuck/broken off bolts too - put a nut over the broken off stud - weld it on, turn it out. Doesn't always work for <really> old rust welded stuff (often on turbochargers) but does work for most stuff. Way better, easier and faster than breaking off easy outs in the bolt.

I had a great time with that at the shop I was just laid off from. "The Boss" had just broken off a tap in a Ducati flywheel chasing red locktite from the threads. I told him I'd get it out but he couldn't watch. Took it in the next room where my Tig welder was, welded a nut on the broken off tap, turned it out easy as pie with a wrench and took it back in the other room all of 5 minutes later. Handed it to the boss - "it's pretty hot still..."

Drove him nuts - I wouldn't tell him what I'd done. "Trade secret..."

Michael
 

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Hey, trade secrets can keep you in work sometimes :)

If I remember correctly the splines were not hardened...at least not enough that it caused a problem. Nothing like the case harding on drive sprockets.
The process is a combo of boring the sprocket and turning down the metal sleeve under the rubber OEM sprocket a bit to smooth it out. You'll notice the OEM shaft is hollow and there is an hole that goes from the hollow center to the needle bearing. I lose this passage using the 6mm hardware as a shaft, so I leave a bit of room between the new setup and the sheet metal mount for oil to get to the bearing.
Careful removal of the OEM shaft might allow for welding the OEM shaft back in instead of using the hardware...might be better for oiling. I've hesistated for fear of over heating the needles. So far plenty of oil seems to sling on the area from various rotating parts nearby.
JohnnyB

BFD, sorry for the thread jack.
 

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Discussion Starter #16
JohnnyB
Yah, I was just thinking that:)

Michael- that method works great for removing swingarm bearing races from an old BMW as well.
Maybe that's the way to go. Was hoping to harvest some from hubs I had but that's probably out of the question now.
 

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Probably the same bushings they still use in various new bikes.

I see that part number available for numerous bikes up to 1982. Still available at $9.72 each (ouch).

# 41241-222-000

JohnnyB

PS. If someone has the clout to do a group buy...I'd pay $5 each for 4 of them.


Edited by - jbranson on Feb 13 2008 12:39:57 PM
 

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Discussion Starter #20
The 175 and 160 show different part #'s. I'm almost positive it's a 160 rear hub but I gotta pull the cover off to verify.
 
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