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Discussion Starter · #1 ·
I have been having trouble throwing the chain off the big ring lately. I have been able to bring it back on by shifting to the small ring then shifting back to the big ring, but this is getting more frequent and annoying.

Still a newbie when it comes to the mechanics so not altogether confident making adjustments or wrenching on my own yet when it pertains to sensitive equipment that I could really mess up.

Any suggestions before I take it to the shop for a once over and tuneup?
 

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Two skinny J's
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Hazy I was taught small chain ring big cog on the cassette = Adjust low limit
Big ring small cog = adjust high limit.

Before you do any adjustments leave it on the small ring and make sure the cable for the front derailuer has enough tension but not to much. To tight and it will never go to the big ring to loose and just the opposite.

You may want to make sure the angle of the rear of the derailuer is correct too.

I'm still pretty novice at it as well but that always works well for me. Maybe a different or better way. Guess we'll see when the pros answer.
 

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Total noob (& forum admin)
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This is odd. As your cable stretches, it would make it harder to overshift. Is the chain actually going past the big ring, and dropping? Before I continue, give us a bit more detail.
 

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Discussion Starter · #4 ·
Honestly I'm thinking I may have some wear on the big ring teeth because the chain sometimes gets thrown without shifting but pedaling fast.

Anyway, I tried some barrel adjustment that seemed to help, but when I tried to shift to small ring, it had a great deal of lag or would not shift at all. I have not tried messing with the screws yet as I have absolutely zero experience with those as of yet.

Oh yea, I could not shift into the highest gear or smallest cogs on my cassette either.

That the info you were looking for or is there something else you need to know?
 

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Total noob (& forum admin)
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How many miles on that drivetrain?

If you use the barrel adjuster, you're removing slack, which prevents you from getting all the way back to the small ring.Undo that, and use the limit screw on the derailleur to prevent over-travel.

With no cable tension, your derailleurs should naturally sit on the small chainring and smallest cog. The tension you place on the from the shifter moves either one in precise increments to the next gear or cog. Proper cable tension, and proper limiter screw adjustments make up all the voodoo and black magic of shifting. True story.
 

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Discussion Starter · #6 ·
Pushin 5000 miles so far. I have been fairly diligent in cleaning and lubing but ha to replace the chain about 700 miles ago.

I'm gonna have to do some book work on the mechanics if I intend to save any money and time on the upkeep of this thing. Zinn and the art of bike repair has been a book recommended . Thoughts on that book??
 

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Total noob (& forum admin)
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So 5,000 on the chainrings and cogs, but 700 on the chain? That could be a problem.

The publisher was nice enough to send me one of the Zinn books, and I found it useful for the newer stuff. Between that and Park Tool, plus Sheldon Brown, anyone should be able to maintain their ride.
 

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Did you replace your chain with the right chain. 9sd and 10sp chains cause more problems up front than back when mixed. Different brands can cause issues with your FD position.

Shifting from large to small on the FD is dependent on tension in the shifting cable. To much tension and the deraileur spring will not pull the chain over.

Always make small adjustments when you are learning. If they dont work adjust back to the original position and try the other way. When using the barrel adjusters count clicks or use clock position as a reference point.

If you cant find the sweet spot I would disconect the cable and begin with adjusting your top and bottom stop.

CHECK VIDEOS ON YOU TUBE!!!!!!!!
 

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I have chain rings with 5 times the amount of miles on yours and they are no where near worn.
 

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Here is a post I put up on another website explaining front derailleur adjustments, hope it helps :)
The front derailleur can only truly be adjusted once the rear gears are spot on. Once the rear is working fine, shift the rear derailleur to the easiest gear or the gear nearest the spokes. Check the front derailleur is parallel with the chainset (crankset)and between 2-3mm above the biggest chainwheel. In this position the front derailleur inside plate should miss the chain by the smallest of margins. If the inside derailleur plate is too far away you need to turn the L or low set screw clockwise 1/4 turn to move the inner plate closer to the chain. So when pedaling uphill in the easiest gear there is no rubbing on the front derailleur. Or 1/4 turn anti-clockwise if the inner plate is touching the chain. Once this is set right, then you need to set the front shifter cable tension. There should be next to no lag in how the shifter moves the cable, meaning when you push on the front shift lever the cable moves the derailleur almost instantly. Adjust as needed. Next it is on to the outer settings, shift into the bikes hardest gears, big ring to smallest rear cog. When you pedal or turn the cranks in this gear is the chain missing the front derailleur? If it is and the chain isn't being thrown over the big ring then your front derailleur is set right. If the chain is rubbing when in the hardest gear then the cable tension of the front derailleur needs to be increased or tightened to move the derailleur out slightly. If you go too far then the derailleur will struggle to drop the chain to the small front ring. If the chain goes over the chainring then the H or high screw needs to be adjusted 1/4 turn(at a time) clockwise to stop this happening. If the chain struggles to shift up to the big ring then back off 1/4 turn anti-clockwise and or check the cable tension is enough to shift the chain up. Phew, I hope this helps.
 
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