RoadBikeReview.com's Forum Archives - Components


Archive Home >> Components(1 2 3 4 5 6 7 8 9 10 )


Front shifting woes/ chainring recommendations.(13 posts)

Front shifting woes/ chainring recommendations.Mike the Snake
Feb 21, 2002 10:15 AM
I am running a 110 BCD crank (Sugino) on my cross bike, with a 50/36 chainring setup (8-spd). I can't get it to reliably upshift to the big ring without adjusting the derailleur so far that I get chain rub from the inside of the derailleur while on the small ring. It looks like there is plenty of throw on the upshift, but the big ring just does not want to catch. I noticed there are no ramps or shift pins on the big ring (Sugino). I am using an old 600 derailleur, and have also tried an XTR 8-spd. Does anyone have experience with either Engagement Rings or American-Made? They are the only other two that come in that size.
re: Front shifting woes/ chainring recommendations.bn
Feb 21, 2002 10:26 AM
Have you maxed out the front D? Some only allow a 12 tooth difference, more modern ones 14. Ramped/pinned big ring would prob help.
re: Front shifting woes/ chainring recommendations.Mike the Snake
Feb 21, 2002 10:31 AM
I'm guessing not, since the stock Shimano setup is a 39/53, and I am running a 36/50, which is the same range.
Have you tried adjusting the cage angle of the FD...Cima Coppi
Feb 21, 2002 12:13 PM
relative to the axis of the chainring? This is often an issue that causes poor shifting up and down the rings. The outside part of the FD cage should be parallel to the chainrings. Another issue could be the age of the chain, which you do not specify. An stretched chain can cause numerous shifting issues with both derailleurs. Start here before changing chainrings. If this does not work, I would recommend upgrading the FD to a better model. Ultegra and D/A FD's are not that expensive, and you will most likely see an immediate shifting improvement.

Park Tool has a good web page on adjusting the FD:

http://www.parktool.com/repair_help/howfix_frontderailleur.shtml

Good luck

CC
re: Front shifting recommendations.Chen2
Feb 21, 2002 12:43 PM
Do you have the derailleur low enough? Normally the outside plate should clear the big chain ring by only 1/8".
-Al
more like 2mmduh!
Feb 21, 2002 2:35 PM
more like 2mmChen2
Feb 21, 2002 3:43 PM
1/8" = 3.175mm. So you are saying 2mm are better than 3mm?
more like 2mmRusty Coggs
Feb 21, 2002 5:33 PM
Yep.
Old trick: use a dime as a spacer...(nm)Samcat
Feb 22, 2002 7:48 AM
Old trick: use a dime as a spacer.?..(nm)Chen2
Feb 22, 2002 9:14 AM
But that's only 1mm, seems a little close to me.
-Al
Nickels are so retro...(nm)Samcat
Feb 22, 2002 1:49 PM
Especially the wooden ones. (nm)grzy
Feb 22, 2002 3:44 PM
That silly millimeterKerry Irons
Feb 22, 2002 5:16 PM
Actually, there is no problem with getting the cage as close to the chain ring as possible. General recommendation in many Shimano manuals has been 1mm for going on 25 years. The only risk you run is forgetting to close to the chainring is if you don't pay attention during setup and there's traces of rubbing. 1 mm works fine.