oilman_15106

Maybe someone will be able to shed some light on this issue. Shimano Ultegra 9 speed triple, front der is braze on. The problem is that when down shifting from the big to middle ring it often shifts all the way to the small ring. The logical thinking is the shifter cable is too tight. But if I make it any looser than it is then when the shift is made up to the big ring the der. housing rubbs the chain. 250 miles total on the group.

I have always set these things up according to the Parks book. Any other ideas than just keep messing with it until the sweet spot is found? Thanks in advance.

Stevie47

Assuming that your chain is in good shape and well lubed, are you possibly making the shift when you are on one of your largest cogs in the rear? The angle that the chain is running at in that gear setup will sometimes cause it to skip the middle chain ring. Doubles will sometimes drop the chain altogether when you do that. If that's not it, yeah it sounds like it just needs tweaking. Shimano's web site has a ton of info on setting it up.

https://bike.shimano.com/catalog/glob...=1170742726635

Good luck

bobkat

chain worn?

NOS88

First two posters have identified the things I'd look at first. Drive components clean? Chain worn? Are you trying to make the shift when on a larger rear cog? All of these could contribute to the chain jumping straight to the lowest chainring. While you indicated that you have a braze on front derailleur, has it been knocked out of alignment or the front cage bent at all?

oilman_15106

Everything has less than 250 miles including the chain. It does not matter what rear cog I am in when shifting down to the middle cog in the front. Everything is clean and properly lubed. Before I go over to road fourms and take triple abuse, any more ideas.

John E

STI's inherent indexing of the front derailleur is a fundamental engineering blunder on Shimano's part, for various reasons. However, with proper adjustment of derailleur height (the bottom edge of the cage should just clear the tops of the chainrings' teeth), limit screws, and cable length, and with some careful experimentation with cadence, pedal load, and manipulation of the shifter, you should be able to solve or at least control the problem.

You may also want to compare the profile of the tops of the teeth of your chainrings against the motion of the bottom edge of the front derailleur cage's inside plate. Some modern front derailleurs are designed for relatively narrow ranges of chainring sizes and progressions.

BluesDawg

Sometimes it helps to go all the way back to square one when adjusting a derailleur. You may already have done this, but when I can't get the adjustments to work, I'll completely loosen the cable and loosen the clamp. Then follow the Park directions in order. Sometimes that will work.

NOS88

OK, let's look at the dynamics of this front shift.

1. With Shimano indexed shifting the front derailleur can only move so far with each throw of the lever.

2. In order for the chain to drop from the largest chain ring to the middle, the chain must come off the large ring only far enough that it drops almost straight down onto the middle ring.

3. There are five primary reasons the chain doesn't drop straight down. One, if the outside of the derailleur cage pushes too far in, the chain will be pushed farther than it should for the middle ring. Hence, you end up on the smallest ring. Two, if the chain is pushed off the larger chain ring with too much force (fast/speed) it will drop farther out than it should. Once again, ending up on the smallest chain ring. Three the chain line (angle of the chain) between the front and rear derailleurs is such that when the chain drops it crosses, in effect, the ideal drop path for both the middle and smallest chain rings. Four, the chain or chain ring is so dirty that when the chain attempts to seat itself, it chatters around and flies off on to the smaller ring. Five, the chain or chain ring is so worn that when the chain drops onto it, it chatters around and flies off much as if it would if it were too dirty.

With the above as reference, you've indicated that you have the problem regardless of which rear cog the chain is on when you shift. So, it's not likely to be a chain alignment issue. You also indicate that the system only has 250 miles on it. This would suggest that it's not likely to be too worn, however, it is still possible. You did not indicate how clean the system is. You can get a system quite dirty in less than 250 miles, depending on where and how you ride. If it is clean, I suggest you shift the front derailleur to the position it should be in when you want to be on the middle chain ring. Now look straight down from above and see where the outside of the cage lines up in terms of the middle chain ring. The outside of the cage should be to the outside of the chain ring or just barely even with it. If it is not, you should trying adjusting until it is. If, however, you find that this is not what's going on, then it is most likely an issue of the chain being pushed off the outside chain ring with too much force and flying past the drop point for the middle chain ring. Try shifting with a softer touch. I agree with one of the previous posts that there is a design flaw in the Shimano front derailleur because it doesn't allow you to trim the derailleur position with any real flexibility. Good luck, and don't worry about the responses you may get on the road forum.... should you venture there.

jppe

As you are experiencing, adjusting a triple seems like more of an art than science. Whenver I would get one "tuned" just right I felt elated and tried really hard to not ever have to change any of the settings. If you can get a triple to not have chain rub on the big ring/harder cogs and smaller ring/easier gears you've won half the battle. The other half is getting it to shift from chain ring to chain ring properly.

BluesDawg's recommendation is mine as well. I suspect it's just a matter of adjustment. Use Shimano's instructions and start all over. I think John E mentions the clearances and all that is important as well and should be spelled out in the instructions. Starting from scratch usually fixes the problem for me for something like that. The main thing is to continue to exercise patience until you get it right......and don't settle for anything but getting it right. It will be extremely aggravating if you have to worry about it not shifting correctly every time you hit the shifter.

Oh yeah, I've had LBS's struggle with the same thing-especially the newbies.......

Good luck!!

Stevie47

Oh, and one more suggestion (you may already have done this) Use some sort of bike stand (mine is home-made) so you can spin the pedals by hand and shift through all the gears while watching very closely what is going on. You can often spot what is causing the problem that way.

Carry on!

cyclezen

of the 3 diff Shimano STI shifters I've now been able to fool with for a bit, the older 8 spd stuff like 105 & Ultegra is really forgiving and still very nice. One set is at about 7K miles and needs no screwin around by me; another is at 3K and like new. The new 10 spd stuff is really top notch and quick, but we'll see how it holds up under miles, currently at about 1.5K miles... The 9 spd stuff is the most finicky... and the least liked by me. 3 sets, all a big PITA compared to the other stuff. I'm considering selling the 9spd stuff off and getting 10spd - but the cassette costs are still 2x a 9spd, so maybe I wait til next season...

I've had those same moments you describe, very frustrating. For myself, I've found - as NOS88 noted - that not having the FD range adjusted on the outer ring, causes problems down the shift line. Loose cable won't solve it, cable always needs to be snug.
If the FD is adjusted so it DOESN'T move outboard far enough, the throw back to the middle ring on the shift will carry the chain further and cause it to slip onto the granny. I now always make sure that the Shift to the big ring is outboard enough, regardless if the chain is already not rubbing on the Big Ring/Small cog setup. Once set out far enough, the throw of the FD on the downshift from Big to middle ring should be right, and usually is for my Ultegra and 105 9 spd triple shifters. But like I said, 9 spd is REALLY finicky and needs some extra foolin sometimes.

EDIT - another thing, remote, but happened recently - on one bike used a bunch, the front shifting went to hell about a month back. Turns out the 'adjuster' which screws into the welded fitting on the headtube had broken and the 'stop' was mostly loose, with some tension provided by the spring under the adjuster nut. But the spring was the shift problem. It had enough 'squish' factor to allow the FD to bounce past the shift point and drop the chain in the granny every time - until I took out the spring and the broken stop adjuster and just ran the cable housing butt up onto the headtube stop. With things firm again, it all worked fine again, although now I can't make front adjustments 'on the fly' - not that that was ever an issue...

Retro Grouch 

Try dialing out the high limit screw about 1/8 turn.

The way that some mechanics set those up is to adjust the cable tension until it shifts right and then they set the high limit screw by tightening the limit screw against the cable tension. If you do it that way, sometimes the derailleur binds up against the stop. If it binds that way, it tends to hang up and then, when it does shift, throws the chain completely over the middle ring.

oilman_15106

The last paragraph is most helpful. Only one question. In centering the cage on the middle ring, is this done with the high limit screw or readjusting the cable tension?

Answer to several responses. Yes you can eat off my drivetrains. They are clean, as is this one. Everything is new Ultegra with 250 frustrating miles, total. Yes I have punted and started over with the whole adjustment proceedure and am getting similar results. The der. height adjustment and chain line look fine.

The only other thing that crossed my mind on a 4 hour plane ride today was cable stretch? Thanks for the help.

brigadon

"........ if the cable does not follow the exact correct route to reach the anchor bolt the resulting parallelogram shape of the mechanism may be distorted and will never shift correctly."

This is part of a reply I wrote to another bike forum recently regarding a problem I had with adjusting my Shimano front shifter.

I struggled for hours to fit a new cable and nothing I did would get the front to shift cleanly to all three rings. In desperation I took it to my LBS and he spotted it straight away.

The last inch or so of cable that attaches to the anchor bolt at the shifter could take one of three different routes, and I'd failed to note which way was the original route before removing the old cable. I had tried the two most logical ones but not the third. Of course the third route was the correct one!

lhbernhardt

I think this should hit it dead on. I stopped using recent Shimano front shifters because they were too hard to shift - the STI lever would not pull hard enough. It wasn't until after I'd switched it out to Campag and I was working in a bike shop that I realized that you have to attach the cable to a Shimano fd anchor bolt in the right place. Usually, the cable doesn't just get clamped as you pull it straight up. Usually, you have to run it *outside* a small flange and then pull it outward and clamp it at the *top* of the bolt. This gives you far more leverage in pulling the derailleur.

And if this doesn't do it (and I'm almost positive it will), please note that Shimano road and mtb fd's shift differently. Are you sure it's an Ultegra fd and you haven't got an mtb fd on there? (I'm sure you don't since it's a braze-on, but I thought I'd just throw that in.)

- L.

NOS88

This is a very good bit of advice I hadn't thought about.

Trsnrtr

Yes, and even bike shop mechanics frequently run the cable under the flange because it "looks" like that's what the flange is made for, but isn't. It's a leverage device.

Here's one of the better links that I've seen describing this:

https://www.hostelshoppe.com/tech_frontderail.php

BluesDawg

I've been using friction shifters so long that I've forgotten what a hassel indexing can be, especially on a front with a triple.

TGYoung

Odd as it may sound, sometimes this sort of behaviour can be caused by sticky cables. If you didn't do so on install, remove the cable, lube it and re-install.

Another possibility is that you're not getting all your "upclicks" in as you shift up due to a too-tight upper limit screw. That is, you may be able to get the chain on to the big ring but the shifter "thinks" it's on the middle ring. Drop the derailleur down to the small ring and un-clamp the cable from the derailleur. Then put a little tension on the cable with one hand and use the other hand on the shifter to shift "up", counting clicks as you go. You should count the same number of clicks when the cable is attached to the derailleur.

oilman_15106

when I get back(yikes 3 weeks) I will check the cable attachment to the front der.and post some comments. I think this whole discussion has been very helpful to anyone reading it. Thanks.

As to ditching the Shimano for Campy, just not ready to take that plunge.

Beverly

It's certainly been helpful to me. I have a similar setup - Shimano Ultegra 10 speed triple and had a couple times when I ended up on the little ring instead of the middle ring. I think the comment to "shift with a softer touch" will solve the problem for me

Hermes

I have not read all the advice so if this is duplicative, sorry in advance. This may be a chain tension issue which is adjusted from the back der. If one increases the tension in the chain, then it is more likely to fall into the middle chain ring than the granny. If the adjustment is putting max tension on the chain already then the other idea is to remove a link and readjust the rear der. The rear der manages the chain tension and slack and impacts front der performance.

stapfam

Hate to say it but all of my bikes have triples, and all of my mates have aswell. The only Bike I had trouble with was the Tandem. I changed one Chainring as It was worn and it was not set at the same spacing from the crank as the others. For some reason I tried to adjust to this new chain ring and only solved the changing problem when I got 2 more chainrings of the same manufacturer. Not saying this is the problem but is the space between the small and middle ring- the same as the middle to Large ring. I have now realised that I could have spaced out the "New" Chainring with spacer washers to get the right spacing and these are only 0.01"---- 10/1,000 of an inch.

oilman_15106

Hate to say it but all my bikes have triples ...... Nothing wrong with that in my book. Lots of riders use them. Even posted this on another discussion. The owner of an LBS I bought a bike from kind of tried to talk me out of buying a bike with a triple. However when he went to Spain on a cycling vacation and rented a bike with one he agreed that they have their place and as age catches up to you he may even switch.

mud

The logical thinking is the shifter cable is too tight.

Could it be that the cable is too loose? It's been my experience that the cable needs to be tightened in order to shift to the bigger ring, and loosened to shift to the smaller ring.

Mud