Suntour Superbe Pro shifting up to 28t or 30t
 

Hi All

I want to see if I can get my great little Suntour Superbe Pro work with a bigger rear freewheel than the 26t max it seems it supports (see: SunTour Superbe derailleur (5300))

Any ideas if there is a way to get this to work with either a max size 28 or 30t rear cog on a freewheel?

Best

Arb

...
...if you want lower gearing, you're way better off with a short cage rear derailleur adhering to the manufacturer's specs for it and just buying and installing at least one smaller chain ring. Assuming that's possible with whatever crank you have now.

Otherwise, it mostly involves fiddling around with rear wheel position in the dropouts, and being satisfied with rear shifting that is less than optimal in the back. Also you usually need a longer chain.

23T is the largest cog it shows supporting.
26T TOTAL CAPACITY.
Look up Chain Wrap to educate yourself.

IF you really need bigger cogs, get a Shimano Tourney. Something "retro" enough to handle relatively wider chains & cogs with minimal rub.

A suntour cyclone GT RD is a fine derailleur that can handle a max cog of 32. They shift nice.

Some folks in C&V have used wolf tooth road link so that the RD can work with a larger cog in the rear; it won't change the capacity of the RD though.

Honestly just buy a quality long cage suntour RD if you want to stay vintage; otherwise get any of the older shimano MTB RDs.

Trying to get the Superbe Pro to work with larger tooth counts is unlikely to give satisfactory shifting performance, lack sufficient chain wrap capacity, and may damage the derailleur. A proper long cage derailleur like the Cyclone GT or V-GT Luxe is a better approach.