I shifted a 9 sp chain over a 44/30 TA with an old Deore fd using Power Ratchets and had no problems except for the somewhat slow upshift. (In fact, I earlier ran a 26/46 with no problem except a very slow upshift.) I don't recall throwing the chain, but then for the sake of best Q with adequate chainstay clearance, I ran the rings in the middle and granny position and so had more room to adjust the fd optimally -- no need to worry about interference with the crank arm.
Not a solution, necessarily, but at least points to the possibility that there *is* a solution. On Fri, Jun 18, 2010 at 10:12 PM, XO-1.org Rough Riders < adventureco...@gmail.com> wrote: > Hi: > > I've never gotten suitable shifting with a TA Pro 5 Vis crankset with > 32/46 rings. This is mated with Shimano 9-speed on the rear (11x34) > and bar-end shifters (Shimano 9 also). First I had it set up with a > Suntour Superbe Pro front derailleur and it wanted to overshift once > every 25 to 50 shifts, no matter how I adjusted the derailleur. > > The local bike guru, who knows stuff old and new, suggested a modern > front derailleur, as they are designed to shifter narrower 9/10-speed > chains, whereas the old Suntour derailleur was meant for 6/7-speed > chains. The thought being: Maybe the "old" derailleur's cage is wider > because the chains for which it was intended were wider; now that > wider cage made it throw a narrow chain too far. That make some > sense. > > Well, I've installed a brand new Ultegra 10-spd front derailleur and > it seems to keep the chain on either one ring or the other, and it > downshifts fine, but it takes a major tug on the shifter to get it to > move the chain to the big ring. In fact, when I upshift, what it's > trying to do is shove the chain between the rings, into the hole > between the five arms of the right crank, in the sizable vertical gap, > or hole, created by the 14 tooth difference in ring size. Of course, > modern rings, with their ramps and pins, would probably toss that > chain right up onto the big ring instantaneously. But I like the low Q- > factor of these TA arms (this is actually my GF's bike I am talking > about; she's 5'4" and prefer the narrower tread even more than I do), > plus the ring sizes available are preferable to a "compact" design. > > Yes, the derailleur is mounted as low as possible abov the top rights. > In fact, the front derailleur cage is so long, it almost hits the > right chainstay down at the bottom. I find that odd since a 46 tooth > big ring is not small, at all. I don't see how this could work on a > crank with a smaller big ring. > > Any thoughts or suggestions? > > BTW, sorry I don't seem to have a good shot of the bike, or especially > its drivetrain online, though you can see her with the bike (gold 1974 > Williams converted to 650B wheels) in front of the Nate Harrison Grade > sign near the bottom of this post: > > http://www.xo-1.org/2008/12/rough-riding-northern-san-diego-county.html > > We're headed out to Ramona / Black Canyon tomorrow and I'll get some > shots of the parts in question then, in case that might help any of > you help me assay the situation. Here's the blog report of a semi- > similar version of the riding we're doing tomorrow: > > http://www.xo-1.org/2009/01/rough-riding-north-eastern-san-diego.html > > Thanks. > > - Chris Kostman > La Jolla, CA > http://www.adventurecorps.com > http://www.XO-1.org > http://www.the508.com > > -- > You received this message because you are subscribed to the Google Groups > "RBW Owners Bunch" group. > To post to this group, send email to rbw-owners-bu...@googlegroups.com. > To unsubscribe from this group, send email to > rbw-owners-bunch+unsubscr...@googlegroups.com<rbw-owners-bunch%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/rbw-owners-bunch?hl=en. > > -- Patrick Moore Albuquerque, NM For professional resumes, contact Patrick Moore, ACRW at resumespecialt...@gmail.com -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bu...@googlegroups.com. To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.
