Mountain Biking - MTB Gear Changing Problem

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View Full Version : MTB Gear Changing Problem


ingsma
10-27-04, 01:32 PM
My MTB will not shift from the middle to the big ring on the front. It just happily grinds away but does nothing. Shifting between the middle and small rings is fine. Any ideas will be helpful.


Gomez308
10-27-04, 01:59 PM
First thing I would do is check the limit screws on the front der. Have you crashed and bent it lately or has it always done this?

a2psyklnut
10-27-04, 02:00 PM
You probably have too much slack in the shifter cable. That or your front derailleur isn't straight.

Can you take a pic of it (from above, looking down)


Do this. Shift into the granny gear. Turn your barrel adjuster all the way "IN", Clockwise, then "out" one full turn. Loosen the cable crimp bolt. Pull all the slack out the cable. Tighten the crimp bolt again.

Shift into the middle ring and big cog. Turn the barrel adjuster so the inside plate barely scrapes the chain then turn it back in until the scraping stops.

Keep it in the middle ring, but shift to the small cog. Turn the barrel adjuster out until it stops scraping.

This will center the front derailleur over the middle chainring and should provide proper shifting into the granny gear and the big ring.

If that doesn't work, chances are your outside limit screw has been screwed inward and is preventing the derailleur from moving far enough outbound.


Mtnbike247365
10-28-04, 11:55 AM
If it is reallly bad, you will have to adjust the shifting cable and tighten it, what I do is I get it on gear 1 and then see if there is any slack in the cable, if there is either use the barral adjuster or tighten the cable. if there is no barral adjuster then loosen the bolt, or the screw. If there is a screw you will use and allen key. if it is a bolt, you will use a small wrench. Then make sure it is on the largest gear on the casette then tighten the cable, shifting through gears back and fourth, also make sure the low end screw isn't too tight or the high end isn't too tight. If you can't get gears like 7 or 8 then loosen the barral adjuster providing more slack to the shifter so it can go to the smallest cog.