At 3/22/2008 11:15 AM -0700, Jerry Moos wrote:
> I do have a couple of SunTour metric FW's but they are mostly too
> narrow a range. I'm considering rebuilding them with more appropriate cogs.
If you need any, I have them all the way up to 38t.
> Can someone advise me on how difficult it is to rebuild SunTour FW's?
The freewheel innards aren't difficult but I don't have time to type
it all out. But it sounds like you just want to remove the cogs.
>How does one disassemble SunTour clusters?
Just hold the largest cog with a chain whip or freewheel vise, then
unscrew as many outer cogs as necessary with a chain whip. Once you
get the all the threaded ones off, the splined ones slide off.
>> To what extent can cogs be interchanged between various SunTour models?
Pro-Compe and Perfect The outer 2 cogs are threaded, whether 5 or 6 speed, the other 3 or 4 are splined. New Winner splined cogs fit, as do the larger of the threaded New Winners.
Winners Had 3 threaded levels on the body. The largest 2 cogs had 8 splines but New Winner 4 spline cogs fit. Pro-Compe and Perfect splined cogs fit if you file the bottom of the splines flat, similar to New Winner.
The small and large threads are unique (at least among SunTour). But the middle had the same threads as Pro-Compe, Perfect and the larger of the two New winner threads.
New Winners (V-1) Had two threaded levels and 2 splined positions. In the splined position, Pro-Compe and Perfect splined cogs fit if you file the bottom of the splines flat. The larger of the threaded position will accept Pro-Compe and Perfect threaded cogs.
The problem with these was that the largest readily available threaded cog was a 21t. So if you tried to build up a touring freewheel you could end up with 21-26-34 as the last 3 cogs on a 7 speed. The original MegaRange. To get around this, I drew up a ring with threads on the inside and splines on the outside. Steve Flagg of QBP found a machinist to produce them as QBP's first "in house" product. With this screwed onto the large threads, you now had 4 large splined positions. I built up several 12-38 seven speeds using these adapters.
New Winners (V-2) At a trade show, Steve showed the adapter to the head of Suntour and tried to explain the need for more splined positions for touring freewheels. Apparently something was lost in translation. The next year a new version of the new winner was introduced with 15 splines cut right through the large threads. You could use either a new type of splined cog or older threaded cogs. Unfortunately the 15 splined cogs were not available in large sizes either. A bonus that I'll wager never got used was then the V-2 bodies had 8 splines on the larger diameter so you could use old, and rare, Winner splined cogs. However the large cogs still had only 4 splines so they could be used on Pro-Compe etc.
Mark Stonich;
BikeSmith Design & Fabrication
5349 Elliot Ave S. Minneapolis, Minnesota 55417 USA
Ph. (612) 824-2372 http://bikesmithdesign.com
http://mnhpva.org