> At 02:04 PM 19/02/2007 -0500, marcus.e.helman@gm.com wrote:
>
> >I have heard that some people are able to get a Nuovo Record
> to shift onto
> >a 28 tooth freewheel cog. I have also heard that 26 is as
> high as the
> >derailleur can reliably go. Clearly there are a number of
> variables at
> >play here. My question is how should I go about setting it
> up? Set the
> >wheel forward in the dropouts to shorten the chain? My
> theory is that
> >this would reduce the slack in the chain. Is it easier to
> do with a 5
> >speed or a 6 speed? Have you tried it? What has worked?
>
> I'm using a Shimano 14-28 7-speed with no problems with a
> SRAM PC-58 chain
> (52-42 chainwheels). My original freewheel was a Suntour
> 6-speed 13-21.
>
> According to Sutherland's, the NR can take up to a 28t
> freewheel and has a
> 24 tooth maximum total capacity (difference between smallest
> & largest
> freewheel, plus difference between smallest and largest
> chainwheels, in my
> case, 14+10=24.)
>
> The only changes I had to make with my 126mm dropout spacing
> to accomodate
> 7 speeds was add about 1mm between the locknut and spacer on
> the RH side
> for chain clearance. Aside from adjusting the RD stops, I
> also found I had
> to set the rear wheel back a bit in my case. (The first time
> around I went
> with a Shimano 14-28 6-speed block and it was completely
> plug-and-play with
> absolutely no adjustments and even the same old chain.) Those
> Shimano
> freewheels with their funny teeth are amazing. Shifting is
> smoother and quieter than it ever was.
The "funny teeth" might make things smoother, but people have successfully used NR derailleurs with 14-28, 5 sprocket freewheels since the 1960s, and with 13-28, 6 sprocket freewheels since the '70s. This was stock equipment on a fair number of bikes.
As John suggests, you need to move the axle back a bit in the dropouts. Also, my recollection is that, unlike modern derailleurs, the old Campagnolo mechanisms actually "preferred" that the chain be a bit slack. Good luck, Fred Rednor - Arlington, Virginia (USA)
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