joejack951

Bike: 2003 Specialized Sequoia Sport, Sora triple FD. Currently has 1250 miles on it and worked flawlessly for the first 1200 miles. Just last week I started having problems getting onto my big chain ring. At first, I'd just have to hold the lever over for a bit and eventually it would shift. Then I'd have to really push and it would go and lastly it just wouldn't shift at all (it would click into position but the chain wouldn't move and I'd have to click it back down). This progression took place over that last 50 miles. I ride mostly on the middle chain ring so this problem only occurred about 3 times during my 20 mile morning rides. Shifting to the small ring was never a problem.

My background is that I'm very experienced working on cars (mechanical engineer as a profession) but I have no experience tuning bikes. When looking at the front cage during the shift, it looked as though it was not moving far enough towards the big ring to complete the shift. This was also evidenced by the rubbing I would get while using the middle ring and the smaller rings on the rear hub. I read through Barnett's sections on front derailleurs and tried adding some tension which helped the rubbing in the middle ring but still did not help me get into the big ring. I then tried to make a larger adjustment by loosening the cable pinch screw and pulling more cable through. This is where things went really wrong. Suddenly, I could not shift at all. It was like my levers lost their detents. Being overly inquisitive, I decided to try and disassemble them a bit and see if I could find anything obviously wrong. What I did find was that if I released all tension from the levers, functioned them a few times, they would eventually start to click into their detents again. I then remounted them, clicked them a few times, and just like they reappeared, the detents were gone again and I could not shift.

So my question is, are my shifters/derailleur bad or am I just completely lost as to how to tune these things? I'm going to feel pretty dumb if I'm just adjusting them wrong (I think they must be broken) but I'll feel even more dumb if I buy new stuff only to have the same problem. Oh and by the way, I like doing everything myself so dropping it off at the LBS is only a last resort option. Then again, I really want to ride this week so I'd like to get this sorted out quickly. Thanks for any help.

Beachbum1546

your cable has just stretched. it happens with all new cables. unscrew your adjusting barrel a few rotations. that should take care of it. your adjusting barrel is probably on your downtube or at the shifter.

joejack951

I tried to adjust the tension with the adjusting barrel and didn't get satisfactory results. The derailleur would not move far enough to complete the shift to the large chain ring. That was when I tried making a larger adjustment and then ran into all these other issues making me think something else is wrong. I'll try a few more times I guess.

Beachbum1546

maybe your limit screws are messed up. figure out which screw causes the FD to move towards the large chainring. screw it in and it should move the FD to your liking.

prestonjb

Basic coments... Probably is cable stretch as stated but could be a limiting screw moved.... So now that you mucked it up how to get it right again? Here are the steps...

0) Disconnect cable...
1) Put chain on smallest chain-ring and largest cog... Lowest gear
2) Adust the LOW STOP on the front D until the inside plate touches the chain... Then back off until it just clears.
3) Make sure front left shifter is in lowest postion (STI press little lever multiple times to make sure
4) Pull out all of the slack from the cable that you can, place it into the binder of the front D and tighten the cable binder bolt (be sure you place the cable through the binder the correct way!

Now the cable should be tight and the bottom adjustment should be right. Now to check the top adjustment...

1) Shift rear to smallest cog.
2) Try to shift into front biggest chain ring.
3) adjust HIGH adjustment until it touches chain on the outside of the front D shift plate. Then back off unitl it does not touch.

If you try and cannot get the thing to shift into the big ring then look to see when you press the shift lever does the front D hit the HIGH adjustment stop... if so LOOSEN the HIGH stop until you can... then go back to #3.

Note... Now if your bike and cranks are stiff enough you won't need to tweek anymore... You may find that to prevent some rubbing under heavy craking you will need to change the stops (move them out a 1/4 turn at most).

Rev.Chuck

Several of the Shimano front der have screw-in pivots (I am pretty sure the Sora does as well) Looking at it from the back you should see two socket screws(3mm) with large heads. Make sure they are tight. If they are even a little loose it will let the cage sit at a poor angle. Once you tighten them they should stay that way. I have seen this enough times that I tighten them when I build a new bike.

srvblues00

I worked in a shop last year that was selling Specialized. We ran into that problem all the time. It basically comes down to the Specialized crank, or at least that's the conclusion we came to. We tried a new/better chain, which helped, but did not fix it. We then put a Shimano crank on the bike, setup the FD, and what do ya know, it worked fine. The spacing between the rings on the Specialized crank might be off just a hair, I'm not quite sure.

We eventually got it to shift sort-of-ok with the Specialized crank. I would suggest lowering the derailleur so that the cage is just barely clearing the big ring. Then, set the limit screw tolerances on the low side really close to the chain. I usually tighten it down until the cage rubs the chain (low-low gear front and back) and then loosen it up a little at a time until it just stops rubbing. Then, I make sure the cable is tight - I'll loosen the anchor bolt, pull the cable tight, then tighten the anchor bolt. Next, use the barrel adjusters to tighten the cable a little more. Once again, tighten until it rubs the chain, then back it off a bit. That's about it for the low side. The high side isn't as critical on these cranks, so I think you'll be ok there.

Also, you might have to play with the angle of the cage in relation to the plane of the chain rings. Sometimes I'd angle it to the outside to assist the chain going up to the middle ring. Also, that would help if the chain is falling off into the frame. Obviously, don't angle/toe it very much - I usually never tow it more than 1mm or maybe 2, but that's only in very rare cases.

Rev.Chuck has a good point - I've seen a lot of of the pivot bolts in ShimaNO front derailleurs loosen up over time. I am no in the habit of checking them if there's any problems or slop in any front derailleurs that I work on.

Good luck.. keep working with it. You'll get it. So you're a car guy, too? I am getting into it a bit myself.. Check out my toy/project/#1 money pit in my signature. It's a blast!

joejack951

Thanks everyone for the detailed explanations. Things are making a lot more sense tonight after I played around with my shifter a bit more. I found out that I had put the front cover on a bit wrong (although consistent with how the other side looked) and that was what was preventing it from clicking into the detents. So now that I know that works, I'm a lot more confident that I can get this bike shifting again. I won't be able to mess with it until tomorrow after work though as it's too late now. I will keep you updated and hopefully be able to report back as to what finally fixed it.

srvblues00: I'm a turbo car fan too. Project #1 is a 1986 Porsche 944 turbo (lots of mods, 330 rwhp) and my daily driver/project #2 is a 1992 Eagle Talon AWD turbo (slightly modded). Both fun cars and the Talon will even get me to the ski slopes with ease I can also fit two bikes in the backseat as I found out this weekend.

srvblues00

It's hard to beat the sound of a spooled turbo, huh? Sounds like you have some pretty fun toys too.. In November I'll have time and money to get back to work on my Mustang. I have a couple plans in the works

joejack951

Progress report: My chain moves again! But...not exactly the way I'd like it to. I attempted to adjust my derailleur per preston and srvblues advice which got me very close but not perfect. I can easily go from small to medium and back to small with no problems and little to no rubbing using all the rear gears. But, shifting to the big ring is still a problem. I can get it to shift, but I need to be on one of the larger gears in the rear to get it to move at all. Otherwise, the cage barely makes contact with the chain. I have my high stop adjustment screw backed all the way out. The derailleur just won't move any more. I also tried lowering the derailleur but it is already as low as it can go. Any lower and it hits the middle ring when I downshift. I thought that if I toed the derailleur in a bit (front end towards the frame moving the backend near the chain) that it might help but it didn't seem to make a difference and just caused more rubbing in other gears.

Based on this, does it sound like I need a new derailleur? It works good enough get me by for the moment but it's going to get real old shifting so much just to get onto the big ring.

demoncyclist

It sounds like you still don't have the FD cable tight enough to allow the shifter to easily move the chain to the big ring.

srvblues00

Try loosening the high limit screw on the front derailleur in 1/8th turn increments... also, recheck the cable tension when the chain is in the lowest chainring. However, don't go too tight on the cable or else you may run into problems with the chain going back down to the smaller rings. Sometimes I have to loosen the high limit screw (big ring) more than I like to get it to shift up well. Usually if it's loosened within reason, the chain won't shift off the crank and onto the pedals. Hope that helps!

joejack951

Ok, not really sure what just happened but I wanted to see if my derailleur had any more movement left in it going towards the big ring. I shifted it into position and then pushed outward with my hand on the cage. It sort of clicked and moved over a little bit more. Lo and behold, the bike now shifts onto the big ring even when on the small gears in back. Seems to me like some dirt must have gotten in there and jammed things up (I thought I kept it reasonably clean but I guess not good enough). I'll know tomorrow morning if my "fix" worked but for now it seems to have. Thanks!

srvblues00

Interesting! Glad the fix was that simple.. hopefully it stays. Does sound kinda like dirt. Have fun on your ride tomorrow!

Beachbum1546

what do you mean by small gears? when shifting you should always have a straight line. So when in the biggest chainring you should be in the smaller cogs in the back. when in the smallest chainring you should be in the biggest cogs in the back.

joejack951

Is this really true? I've never made any attempt to try and keep my chain straight when shifting on the front. And before two weeks ago, I never had a problem with it. And, as of this morning, my bike is back shifting smoothly again! Flawless actually. The shift from my middle ring to the big one has never felt so smooth or completed so quickly. Thanks everyone for saving me some money and teaching me some new things along the way.

demoncyclist

You want to stay away from the cross-chain combos: Big ring/big cog and small ring/small cog. They can place too much side load on the chain, and can cause rapid drivetrain wear.

prestonjb

I'll add that this combination you don't want to stay in... Sometimes when trying to shift around or so and you may end up in one of these combinations is OK... Just know you don't want to be there and take slow but immediate action to remove yourself from that condition.