Chain rubs inner front derailleur while in lowest gear.
I changed compact cranks to standard. SRAM Force crank with 11-26 SRAM cassette, all other components are Dura Ace. Chain rubs inner front derailleur, small on big 3 lowest gears. With current adjustments I can no longer shift for 1/4 out to adjust for high gear chain rubbing. Is my problem the mismatch of componets? My bike is a Trek Madone 5.5 size 50.
Re: Chain rubs inner front derailleur while in lowest...
On front derailleurs there should be two small cross head screws one has L(lower) next to it the other has H(higher), you will need a cross head srewdriver, you simply losten or tighten the 2 screws and it will adjust the position of the derailleur to your crankset and it that completely fails then you might need to try a different crankset
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Ditto for the rear. All 9-speed cassettes and chains will work, depending on what brand your cassette body is. Your gear ranges and selections are up to you and your legs. A little web searching answers a lot of questions.
For the wide range of gearing on a MTB, the rear derailleur has to be able to adjust a large amount. If you shift into the smallest front chainwheel and the smallest cog on the rear (position 1), you'll probably see the chain is very loose and the rear derailleur is pointed back horizontally. Conversely, if in the largest front chainwheel and the largest rear cog, the derailleur will be pointed forward (position 2)
Couple things to do:
1) Avoid the gearing combination of the smallest cogs. Instead, use the middle chain ring and a larger cog (you'll have the same net gear ratio).
2) You can remove a link from the chain. A chain tool is about $10.00. You push the pin out through all but the last plate on two links, bend the chain slightly to pop those 2 links out (2 links = a wide link + a narrow link), then put the chain back together. This is only advisable if in position 2 there is some additional travel for the derailleur and in position 1, the derailleur has no additional travel.
3) Make sure your chainrings aren't bent, straighten (use a open-end wrench and gently pull the chain ring back to flat). This isn't likely b/c you don't indicate the chain falls off while shifting.
4). If the chain falls of the inside, screw in about 1/4 turn the inner limit screw on the front deraillleur. If the chain falls off the outside, screw in about 1/4 to 1/2 turn the outer limit screw on the front derailleur.
Derailleur adjustment takes time to master. Try this out:
First, wash your drive train out really thoroughly and use a degreaser (Simple Green works really well) and a chain brush on the derailleur and chain. Rinse it off and let it dry, then relubricate the chain (and ONLY the chain - never lubricate your derailleur). Now flip your bike onto the bars and saddle so you can crank while you shift manually. Use the middle chainring up front to adjust the rear gears. Okay, shift into your highest gear in the back and then release the derailleur cable. Use this opportunity to make certain your "H" setting is good; the derailleur's jockey wheel should be perfectly aligned over the small cog. Now manually push the derailleur to the lowest gear (while pedaling) and set the "L" so the jockey wheel is immediately outside the last cog. crank back to the high gear. Turn the barrel adjuster for the cable tension to its half-way point (figured by unscrewing it all the way and then counting revolutions as you screw it back in). Pull the cable taut and reattach it. Shift into your middle gear (or if it is an even number of gears, pick one of the two middle gears). Use the barrel adjuster to get the jockey wheel exactly over the correct cog. Pedal and shift through the gears. In each gear, back-pedal to make sure the chain is not skipping. You should be able to free-wheel without problem in every gear on a properly adjusted drive train. If the gears are requiring much adjustment on the barrel adjuster, then you may have a bent derailleur hanger. This can be straightened manually without tools if you have a good eye and patience. If it goe that far, come back and repost "bent derailleur hanger".
Wash, degrease and scrub the chain and derailleurs with a good degreaser (like Simple Green). Dry the chain and relubricate it with an appropriate bike chain lubricant (not oil or WD-40). Shift the derailleurs to the smallest chain ring and cog on the cassette (low front gear, high rear gear) and then loosen the cable at the derailleurs, pull the cables taut and reattach them. If the derailleurs still need adjustment, here is a procedure for it:
Flip the bike over (so you can pedal the bike manually while you shift) and shift the front to the middle chain ring. Shift the rear to the highest gear (small cog). Release the cable from the pinch bolt on the derailleur. Adjust the screw marked "H" on the derailleur until the jockey wheel on the derailleur is aligned perfectly over the small cassette cog. Set the cable adjuster on the derailleur to the middle of its range (find this by screwing it all the way in and then count how many revolutions it makes until it screws out completely. Screw it back in one half of the total revolutions). Reattach the cable and shift to the lowest gear (the biggest cog). Over-shift and hold on the shifter, then adjust the "L" screw on the derailleur until the jockey wheel sits just past the last cog. You have to hold the shifter to do this. Now shift into the middle gear (or one of the two middle gears if the bike has an even number of gears) and adjust the derailleur using the barrel adjuster you previously set to the middle of its range. Adjust it so that the derailleur is sitting perfectly over the appropriate gear. Shift up and down the cassette while pedaling and in every gear, reverse pedal (freewheel) to make sure the chain does not hop. Adjust as necessary until all gears are smooth.
Now the front:
Set the rear derailleur to the lowest gear (big cog) and the front to the lowest gear (small chain ring). Disconnect the derailleur cable. Screw in the adjuster for the cable tension all the way (this adjuster is on the shifter of a mountain bike or the down tube of a road bike). Pedal to make sure the chain is not rubbing on the derailleur cage. If it is, adjust the "L" setting on the derailleur until the chain moves by without touching the cage. Now pull taut and reattch the cable and shift the front to the big ring while pedaling. If it does not shift up well or completely, hold the shifter past its normal shift and adjust the "H" screw so that the derailleur allows the shift. Shift into the highest cassette gear and keep pedaling. The chain should not be touching the front derailleur's cage when you pedal. Adjust with the barrel adjuster until the chain moves freely without touching the derailleur cage.
That should be it, unless there is another mechanical problem causing the missed shifts, like a bent derailleur hanger or damaged teeth on the cassette cogs or a bad derailleur. If it is still problematic, come back for further information.
You might have to consider changing your bottom bracket for one with a longer shaft. Examine your chain line and do some research here:http://www.parktool.com/ and also here:http://sheldonbrown.com/gearing/index.html
Oh, it is too bad you are in the Bronx. i'd have that fixed right quick. There are probably a pair of culprits at work here. One, your derailleurs no doubt need adjustment. Two, your rear derailleur hanger may be bent. These two can both cause the problem. Start with the rear hanger, because that will be easier to see.
Flip the bike onto the bars and saddle and take a look at your rear derailleur. Is it going straight up and down and is it aiming straight with your frame? If it isn't, you have found your problem. The hanger needs to be straightened. This can be done without any tools if you have a good eye. Hold the derailleur by the body and bend it to make the alignment good with the cassette. If this is NOT the problem (but i really think it is) then here is a walk-through on adjusting your derailleurs and hopefully this will solve it.
Here is how to adjust the rear (first): -Set your front gear to its middle position. -Shift the rear into the highest gear. -Disconnect the derailleur cable. -Screw the barrel adjuster on the shifter (or down tube if it is a road bike) to fully turned in clockwise. Screw the barrel adjuster on the rear derailleur to its halfway point. -On the back of the rear derailleur you will see two screws. One will be marked "H" and the other "L". These mean high and low. Adjust high to get your jockey wheel on your derailleur perfectly centered over the smallest cog on the cassette. Manually shift by pushing the derailleur (while cranking the pedals) to the largest cog (1st gear) and set this stop on the derailleur "L" where the jockey wheel is over the cog, but past it where it would be touching the outside of the cog if they were side-by-side. -Pull the derailleur cable taut and re-tighten it. Shift the rear to the middle gear and adjust the derailleur using the barrel adjuster to center the jockey wheel directly over the cog it should be. -Now shift up and down the cassette, cranking as you go and in every gear, back-pedal to make sure there is no problem with the gears hopping. If they do, adjust as necessary with the barrel adjuster. Here are some tips for the front: -Shift into low gear on the front and rear derailleurs. Make sure the chain is not rubbing on the front derailleur. If it is, adjust the screw marked "L" until the chain just clears the derailleur but does not touch it. -Pull the derailleur cable taut and re-tighten it. -Now shift the front into the middle gear and while it is still in the low gear in the back, crank to make sure the chain is not rubbing on the front derailleur. If it does, adjust the tension of the cable with its barrel adjuster. -Shift the front into high gear and shift the rear to the highest gear, cranking as you shift. If the chain is not rubbing, you are all set.
Make sure your rear derailleur is lined up with one of the rings of teeth on your rear gears( cassette ). Also make sure Your chain is riding correctly on one of the front gears on your crank. If you are still unable to back pedal make sure that one of the cogs (gears) in the rear derailleur arm isn't seized. They must both be able to rotate and the chain should pass through them in a backward S pattern. If you still can't back pedal remove the back wheel or move the chain off the cassette to see if the cassette will freewheel. It has to move freely in a counterclockwise direction in order for you to backpedal. Moving in a clockwise direction engages pawls inside the cassette which lock it into a drive situation which propels the bike. If the cassette will not freewheel in a counterclockwise direction you will need to take the rear wheel to a good bicycle shop to have the cassette replaced. It requires a special tool to remove it. Hope this helps.
If you replaced the chain yourself , you may have left it too long. With the chain on the biggest cog on the rear and the biggest cog on the front , pull the two ends of the chain together and see where they will link up. Leave another two links in the chain and it should be the correct length. You may also have the wrong chain for the bike. Also carefully check each tooth on each cog front and back for wear. Also check the idler wheels in your rear derailleur.