Compact Double
 

Hi. hope all are well... I would like to know what you guys think is the Best Suntour rear derailleur for a compact double is ... say a 34/48 ? a SuperBe Pro ? I've used a model V and a V GT seems like a short cage doesn't really work well with freewheel i have.. Regina America 12/21 ... so what do you think ?

any and all info thanks a Ton...


rc50

I am no expert but I have put 3 compacts on bikes. I don't think the freewheel is too wide a range for any of those derailleurs. The total chain uptake with the compact wouldn't be difficult for most modern derailleurs.

I am sure the mechanics on the list have a better way but to measure uptake. I open up the chain and put it on a middle cog and the largest ring at the minimum tension I would want on the chain. I then pull the chain until the derailleur is out straight and count the difference in links and this is what I have used for the maximum uptake. Take the difference between the rings and the difference between the largest and smallest cog add that together and you know the takeup you need.

As an alternative to the compact have you looked at a wider range freewheel? You can probably get to a 28 with those derailleurs. Someone here will know that for sure. Ron

The rear derailleur doesn't care which crank you have, only the total teeth. The compact you are proposing only has a 14T difference which is the same as the common 53/39 road double.