Join Date: Oct 2005
Location: SW Ohio
Bikes: Puch Marco Polo, Saint Tropez, Masi Gran Criterium
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Sora front triple index difficulties with 30-44-48 crank
So I'm setting up this really cool women's specific 1883 Cannondale touring triple with interesting, rare ERTO 590 wheels and tires. A worthy project we thought. Everything is great and the bike is just about out the door with Sora 3 x 7 triple seven speed sti brifters. 7 speed rear s.i.s thread on freewheel with Shimano Light Action s.i.s. rear derailleur - a snap - the stuff works beautiful with the new Taya turbo chain. Triple front crank has 94 bcd chainrings in a 30-44-48 sorta halfstep with granny, sorta commuterbike mild gearing. Old friction front derailleur was a SunTour cyclone endless band. I decided to try a Shimano Deore (interestingly it also has Shimano's version of endless band). I went to the bikeshop and got a little nylon spacer for the front derailleur band to bring a 35mm down to a 31.8 mm to match the Cannondale seat-tube. The Deore front derailleur is engraved on the back of the cage "half-step" - interesting - I'm thinking - if anything has a shot of indexing on the first (or second, or third, or fourth
) try, this could be my ticket to precision.
So I set the thing up...I must add that I'm a downtube shifter kind of mechanic, a little too old school I guess. Anyway, setting up the Sora Shifters was much easier than I thought.
The problem is the grinding in the middle chainring mainly,only a few rear cogs are immune. The Sora shifts into 3 positions with very positive CLUNKs (as opposed to the rear where its satiny smooth light action quietness). I'm bidding on some 105 triple 31.8 FD's on ebay right now but I keep losing the auctions.
Can anyway direct me on how to get this funky half step triple crank to index better with the Sora brifter ? Thanks.