Pilgrim said:Hello, as you've all probably figured out by now, I'm gearing my bike-
boom road bike up for touring. After a trip up Devil's Slide this
weekend I discovered I need a lower gear range. Currently I have a
dual ring set-up (I don't know the tooth count off hand) and it looks
like there used to be a third ring bolted on, but it's gone.
If your Sugino crank has provisions for a third chainring, it is
almost certainly a 74mm bolt circle diameter. That means you can put a
chain ring as small as 24T on the crank.
Quoted message said:I have
SunTour AR front and rear dérailleurs.
My questions;
Can the front dérailleur be adjusted to use three rings?
The Suntour AR FDs I recall had a fairly deep inner cage plate, so
yes, a triple should work. As the inner ring gets smaller (i.e., 28 v.
26 v. 24) the shifting will get less wonderful to and from the little
ring.
Quoted message said:
Will the short cage of my rear deraileur suffice to take up the slack
when I'm in the low gear?
Yes, if you only use the third chainring on the larger rear cogs.
That's all you really need to use to get a low gear, anyway, the other
ratios are duplicated on your middle chainring.
BTW, your RD will easily take a 28T rear cog, and probably a 30t, so
calculate your low gear needs from there.
Also, as Andrew Muzi mentioned yesterday, you might want to consider
moving to a 7SP freewheel and new front and rear derailleurs in the
future.
Quoted message said:
Pictures here:http://flickr.com/photos/simpolman
Pilgrim