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Newbie question - chain jumping off


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HI All,



i am new to cycling, trying to get ready for the 94.7


i have experienced this problem on 2 or 3 road rides

i will be riding and get onto a nice flat road where i can climb to the bigger gear in front and the smallest at the back....

problem comes in when i hit an incline and want to shift off the top gear in front to the smaller gear......


problem is the chain jumps off and i land up kissing the tar as i cant un-cleat in time..... cleats and falling is a whole other issue :) :)


do i need to do some adjustments on my gears?


i have a cannondale SAAD with Shimano 105


please could someone help with advise as this problem is now slowing me down as i am scared to use the bigger gear in front




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Your front derailure has two small adjustment screws which sets the bottom and top stop position. Normally when your chain falls of when shifting from the big to the small chain ring the bottom stop screw needs to be adjusted so that the FD stops at the correct place. Yours goes too close to the frame hence it throws the chain too far and the chain falls of. If you have not adjusted gears before rather take it to your LBS to adjust properly. If you just adjust the stop you might mess around the trim settings of the 105 or not be in the right gears when you adjust the settings.

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Generally, the problem can be fixed by properly setting the limit screws on the front derailleur, as described by FeO. You can also avoid it by backing off the power a bit when you do the front shift.


Sometimes, though, the specific groupset and frame combination makes it difficult to get a setting that stops the chain jumping while also stopping it from rubbing in extreme high and low gear ratios. In this case, you can get a chain catcher that will stop the chain from overshifting:


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If the front derailer is slightly too high on the downtube it can also contribute to the problem. Although not complicated, I find the FD more difficult to set properly than the rear. I will gladly assist if you need. Based near Fourways. 072 222 7185

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There is also a little gadget called a "Dog Fang" that clamps onto the seat tube.(was about R60-00 from Bruce Reyneke in Lynnwood Rd) I run a compact and had the same problem with sudden shifts. The Dog Fang prevents the chain from overshooting the small chainring...

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