5sp to 6sp on 122mm ok?

shawnb

Senior Retro Guru
I have a 5 speed no name freewheel on my gios that has a 28t top cog which is unuseable due the nuovo record rear der not being able to accomodate it. Can I go up to a 6sp freewheel ok on 122mm rear spacing? there's lots more choice if I can !

Thanks!
 
http://sheldonbrown.com/cribsheet-spacing.html

http://sheldonbrown.com/speeds.html

Looks like you might have to spring your dropouts apart slightly since standard 6 speed is 126mm, but it might be doable. Presumably you'll also need a longer axle and more spacers outside the cones. My reading of this suggests that if you can get hold of an ultra-6 freewheel and use a modern chain with sticky-out rivets, it will require less of a change (ETA - assuming you're not using indexed shifters)

I've not done this (although I'm considering something similar), so I could be completely wrong.
 
Thanks, completely forgot about the Sheldon Brown info. With a little refining of my searching on ebay I have found a 5sp silver nos '77 regina freewheel that will keep the originality :D
 
Elev12k":239pxr16 said:
The NR mech handles the 28t largest on my bike btw.

Well this got me thinking, the previous owners nos sachs chain looked a little too loose so I removed a couple of links and hey presto the top jockey wheel doesn't rub the underside of the 28t cog. The tighter chain pulls the top jockey wheel furthur down away from the freewheel. Problem (simply) sorted, a nice hill climbing set up :D

Cheers all.
 
28 cog was always a bit hit and miss with Campag NR, I always wondered if some droputs had longer mech hangers?

There is always the suntour winner 6 speed system if you really need a 6 speed :)

Shaun
 
shawnb":1ksdd7l2 said:
Elev12k":1ksdd7l2 said:
The NR mech handles the 28t largest on my bike btw.

Well this got me thinking, the previous owners nos sachs chain looked a little too loose so I removed a couple of links and hey presto the top jockey wheel doesn't rub the underside of the 28t cog. The tighter chain pulls the top jockey wheel furthur down away from the freewheel. Problem (simply) sorted, a nice hill climbing set up :D

Cheers all.

Isn't the b-tension screw (or whatever the equivalent on non-shimano things) meant to take care of this. Wind it in to move the top jockey wheel away from the sprockets.
 
I'll take a look when I get home but it didn't stand out when I was tinkering, would it have one being a pat 78 era? Whatever the issue has been sorted by shortening the nos chain that the seller had just slapped on. Reckon I could do the south downs way with this gearing!! It's like a MTb set up!!
 
flimflam_machine":135yz7vn said:
shawnb":135yz7vn said:
Elev12k":135yz7vn said:
The NR mech handles the 28t largest on my bike btw.

Well this got me thinking, the previous owners nos sachs chain looked a little too loose so I removed a couple of links and hey presto the top jockey wheel doesn't rub the underside of the 28t cog. The tighter chain pulls the top jockey wheel furthur down away from the freewheel. Problem (simply) sorted, a nice hill climbing set up :D

Cheers all.

Isn't the b-tension screw (or whatever the equivalent on non-shimano things) meant to take care of this. Wind it in to move the top jockey wheel away from the sprockets.

Those old Campag mechs didn't have such a thing.

The mech hanger does play a part in getting the mech to handle 28T. I found that I had to shorten the chain so far on my bike that the rear mech (an SR not NR - makes no difference really) was way too tight on the big ring. In the end I just gave up and made do with a 24T bottom sprocket.

Mark.
 
My Super Record of that vintage dealt with a 30 by shortening the chain.
However I have also bunged a 6 speed block into a 120mm alloy cyclocross frame. It will go. Just
 
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