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-   -   road bike 2 x 9 front derailleur problem...getting stuck in middle (https://www.bikeforums.net/bicycle-mechanics/770110-road-bike-2-x-9-front-derailleur-problem-getting-stuck-middle.html)

illdthedj 09-22-11 02:53 PM

road bike 2 x 9 front derailleur problem...getting stuck in middle
 
hello!

i have a bianchi campione road bike frame that ive built up.
9 speed ultegra cassette, 9 speed ultegra rear derailleur, 9 speed chain...
that is all working wonderfully.

up front is some older sugino double crankset with 50/39 chainrings. and a shimano 600 front derailleur. using a ultegra barcon shifter on the downtube for the front.

my problem is this:
when shifting from high to low chainring, the chain gets a little stuck in the middle.
I have already done some research on this, and i have eliviated the problem some when i realized i had the small ring on backwards. However, fixing that, it goes from falling into the middle of the two chainrings to sort of skating on top of the small ring, but not exactly falling into place like it should.

is my problem that the crankset/chainrings are meant for an 8 speed chain and im using a 9 speed chain? should i get an 8 speed chain to fix this? or would using an 8 speed chain on 9 speed cassette/derailleur be problematic?

thanks for your help!

HillRider 09-22-11 03:33 PM

First, you can't use an 8-speed chain on a 9-speed cassette so you are stuck with your current chain width.

You are correct that 8-speed era cranks had the chainrings spaced slightly farther apart than 9 and 10-speed cranks so the narrow chain can "skate" if you don't make your shifts cleanly. Proper shifting should avoid this and, since you are using friction shifting in front you have quite a bit of latitude. I'd set the front derailleur's low limit screw to allow the front derailleur to move the chain all the way over almost too far then trim it back slightly to avoid rubbing. A "chain watcher" can be used to be sure you don't spill the chain to the inside.

dsbrantjr 09-22-11 06:11 PM

illdthedj: +1 on the chain watcher. It will allow you to aggressively adjust your low limit screw to allow crisp downshifts to your small ring. May favorite is the N-Gear Jump Stop - http://www.gvtc.com/~ngear/
Make sure your derailleur pivots are lubricated and the shift cable moves freely to keep from slowing down the shift, since the derailleur spring supplies all of the force that is moving the chain over. You want it to "snap" into position rather than settling in.


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