Mountain Bike Won T Shift Into High Gear
When sitting and riding on mountain bike front gears will not shift.
Mountain bike won t shift into high gear. I am often asked how to fix a bike that won t shift gears or will only shift to some gears. Visually check that the upper derailleur cage is in line beneath the largest rear sprocket. The rear derailleur seems to work that is it shift from the small sprocket to the largest but it will not stay in anything beyond the the small one. Front derailleur won t shift into third largest gear.
The front shifter is a shimano integrated brake and shift assembly. If the chain won t run to the bottom of the cassette and shifts over the big cog into the spokes or vice versa it sounds like a bent rear hanger needs straightening or replacing. It s a 12 speed with the gear shift on the lower bar. When you shift into the lowest gear you are putting direct pressure on the derailleur via cable tension and the limit screw is what keeps it from going too far and falling off the cassette.
Shift into the lowest gear largest rear sprocket. The problem will be the shifters derailleurs or cables. Hardrock mountain bike. I can go between 5th 6th and 7th gears but trying to go any lower than 5 won t work as there s just too much resistance from the shifter.
I walk through the steps to isolate and locate. Hi i have an older road bike. The rear derailleur is the heart of most mountain bike drivetrains. The rear shifter starts at 7th top gear and releases downward towards gears with less resistance.
If it is not adjust the limit screw until the. The front derailleur groupo is shimano sis. The shift cable pulls against the derailleur s spring to shift into lower gears and releases cable tension to allow the same spring to pull the derailleur into higher gears. I can pull the cable to make the derailleur shift into third but the shifter doesn t have enough throw to do it via the shifter.
That holds down the shifting cable to allow the derailleur to reset to it s natural position before setting the high low screws. I show the steps how to diagnose and repair a rear derailleur that wont shift to the high gears small cogs.