Shimano Postiron FH derailleur

[krisinpdx]

Hello all!

I have an old Schwinn World Tourist Bike that I'm reconditioning. It's
a five speed with the freewheel in the crank. It uses a Shimano
Positron FH rear derailleur (which is damaged).

So, the $1,000,000 question is: Keeping everything else the same, can
I replace the derailleur and shifter with something more modern? Is it
as simple as finding a short cage 5 or 6 speed derailleur, or is the
positron derailleur unique in some way?

Thanks for any words of wisdom.

Kris

[bicycle_disciple]

u might have compatibility issues. for that same cost of the
components, u can buy a cheap and good enough steel road bike to handle
those extra distances u'll give it. whats ur budget?

[JeffWills]

krisinpdx wrote:
> Hello all!
>
> I have an old Schwinn World Tourist Bike that I'm reconditioning. It's
> a five speed with the freewheel in the crank. It uses a Shimano
> Positron FH rear derailleur (which is damaged).
>
> So, the $1,000,000 question is: Keeping everything else the same, can
> I replace the derailleur and shifter with something more modern? Is it
> as simple as finding a short cage 5 or 6 speed derailleur, or is the
> positron derailleur unique in some way?
>
> Thanks for any words of wisdom.
>
> Kris

Shimano Positron derailleurs and shifters are somewhat unique and only
work with each other. You can read about here:
http://www.sheldonbrown.com/shimano1982/pages/36.html

If you replace the derailleur, you need to replace the shifter and the
cable as well. Given that, it's a straightforward job. A "standard"
derailleur and shifter will work fine.

Jeff