Chain rub on a triple?

[jgugelm]

My new bike has Ultegra Triple up front and I am getting quite a bit of chain rub when I'm in the small (granny) ring up front. I can hit the 4 biggest cogs in back without any rub but if I go past that it gets pretty bad. I went back to the shop and the tech hit the L limit screw with some minor adjustments and said it was fixed. After test riding in the parking lot and noticing no difference I went back and asked him to try again. He did and told me it was fixed but that I should never shift past the 4th or 5th smallest cog in the back. That effectively means I only have 4 or 5 gears available when I'm in the small cog.

Now I know I'm not supposed to cross-shift (small-small/big-big) but I would hope I could get at least 5-7 of the cogs in the back when I'm in the smallest ring up front. The big ring only rubs on about 2 of the big cogs in back. I'm willing to live with a 23 speed bike on a 27 speed drivetrain ... but 19, or worse 17? Does this seem reasonable?

I left thinking I'd either live with it or take it back when a tech. who seemed more interested in helping me was around.

So .... my ?'s are:

1) How many cogs should I be able to shift into without chain rub (while in the small or big rings up front?)

2) Anyone have any guidance on fixing this on my own. I'm reasonably competent around a MTB drivetrain and am assuming the road isn't that much different.

Thanks!

 

[jtfleming]

I have 24 speeds and no problems in any gear combination at anytime on a Shimano. I am no bike mechanic, but the front derailleur may be too far to the left? did you check that?

 

[Snarl]

My Wife has an Ultegra Triple with 9 Speed on the rear and we can get without chain rub;
Small Chainring 6 Gears
Middle Chainring 9 Gears
Large Chainring 7 Gears
I believe thats about the best you can get due to the extreme drive angles and the width of the Front derailer cage.

When it came from the bike shop I did'nt get this many Gears so I had to re-set every thing up. if anyone can get all 27 Gears without chain rub I'd love to know how .

 

[jgugelm]

Thanks Snarl,

Makes me feel a little better I suppose. I still feel cheated that they can market something as 27 speeds even though you can only ride about 23 (if you're lucky!) Any recommendations on 'workflow' for getting it fixed. Right now, I'm trying to follow:

FD height
FD rotation
Lower limit
High limit
Cable tension

I think I have the FD height and rotation almost nailed but am struggling with getting the limits correct. Also, I'm a little shaky with getting the cable tension correct. Moving from middle to big ring requires an act of brute strength. Is the cable too tight? Too loose? Also, the barrel adjusters are different than I'm used to on my MTB. Is it counter-clockwise to take up cable or vice versa. BTW, the adjusters are on the down tube, not the shifters (like most road bikes?)

Thanks!

 

[jitteringjr]

Now I'm glad I picked a double, at least I get full useage out of it. I didn't know that about triples though before this. That is annoying.

 

[Snarl]

jgugelm;
Go to park tools website and look under their repair help section for derailer adjustments.

Try this link;
http://www.parktool.com/repair_help/FAQindex.shtml

I have an Ultegra Double and I still get a little Chain Rub on on the front derailer cage at Extreme angles. I beleive Shimano somewhat admits this in their technical information section on the Indexed Shifters, thus some models had a partial shift position that provided some trim. It is my understanding that this is an advantage Campagnelo has, trim adjustment.

Note the following rip from Parks site;

Front Derailleur Performance
The front derailleur should shift the chain between chainrings without throwing the chain off the extreme outer and inner rings. It is possible that the front derailleur will rub the chain slightly even on properly adjusted bikes. This is likely on some bikes when riding in the largest sprocket in front and the smallest cog in back. As the bike is pedaled with force the frame flexes and moves the chainrings side to side, which cause an intermittent rubbing noise. Loosening the H-limit would move the front cage out more, and may stop the rubbing, but it may also cause the chain to shift over the largest ring and come off. If all aspects of front derailleur adjustments are correct on this bike, the rider is simply exceeding the engineering and design capabilities of the machine.

 

[rider]

Originally posted by jgugelm
My new bike has Ultegra Triple up front and I am getting quite a bit of chain rub when I'm in the small (granny) ring up front. I can hit the 4 biggest cogs in back without any rub but if I go past that it gets pretty bad. I went back to the shop and the tech hit the L limit screw with some minor adjustments and said it was fixed. After test riding in the parking lot and noticing no difference I went back and asked him to try again. He did and told me it was fixed but that I should never shift past the 4th or 5th smallest cog in the back. That effectively means I only have 4 or 5 gears available when I'm in the small cog.

Now I know I'm not supposed to cross-shift (small-small/big-big) but I would hope I could get at least 5-7 of the cogs in the back when I'm in the smallest ring up front. The big ring only rubs on about 2 of the big cogs in back. I'm willing to live with a 23 speed bike on a 27 speed drivetrain ... but 19, or worse 17? Does this seem reasonable?

I left thinking I'd either live with it or take it back when a tech. who seemed more interested in helping me was around.

So .... my ?'s are:

1) How many cogs should I be able to shift into without chain rub (while in the small or big rings up front?)

2) Anyone have any guidance on fixing this on my own. I'm reasonably competent around a MTB drivetrain and am assuming the road isn't that much different.

Thanks!

You should be able to engaged all gears in an all Ultegra set up.
With Shimano transmission the set up has to be precise where as the Campagnolo transmission is more forgiving.
I have an Ultegra cassette (12-27) with a triple chainring (48-38-28) and I can engaged all gears without chaing rub, except for the large-large gear when ithe chain rubs just a little, but since that's a gear I rarely engaged it doesn't bother me.
To avoid chain rubbing use of the trimming facility in the Ultegra STI levers must be used. This trimming facility only helps if everything else is precisely set for your particular bike.

 

[tourdelivermore]

Rider has it right...there are index positions between each chainring.

I set up my Ultegra triple and can reach all cogs from all rings without rub except the two largest cogs from the the big ring.

Position 1 - small ring
Position 2 - small ring +
Position 3 - middle ring -
Position 4 - middle ring
Position 5 - middle ring +
Position 6 - big ring

You get to the - and + positions with 'half clicks' from the shifter.

The internet has several good articles on how to set this up...that's where I learned the technique. I used this source from cyclingnews.com:

http://www.cyclingnews.com/tech/fix/?id=frontmech

It works well. The sooner you start doing this yourself, the happier you will be with the set up of your ride.

Good Luck.

 

[Snarl]

I believe the Shimano Trim adjustment is only availiable on the small black lever on a Large Chain Ring to Sprocket combo on the FD-6500 or 5500 Doubles. It appears that on the FD-6503 or 5503 this trim is not availiable. This may be confirmed at the following link;

http://bike.shimano.com/Road/Ultegra/componenttemplate.asp?partnumber=ST-6510

Then check the Service Instruction for the Shift lever.

Also note that I have set up my driveline many times and different bikes and although I'm definitely no Pro I have never seen a Shimano Indexed setup without at least minimal chain rub on extreme gears. I cannot honestly say it's impossible but I just have'nt seen it, even our local Bike Shop can't do anything. No this doesn't mean the Gears aren't availiable just that they may be a bit noisy.

Good Luck !

 

[rek]

It is sometimes possible to set up a triple with no rub in any cogs (I've been able to do this with my MTB a few times), but it takes a lot of patience, and you end up having to fine tune it fairly often to keep everything perfect.

Often it's just easier to just let the chain rub on the gears you very seldom use (and optimise the shifting for gears you actually use), or take advantage of the lever trim-positions (if you've got them.)

 

[rickwarner]

Originally posted by Snarl
I believe the Shimano Trim adjustment is only availiable on the small black lever on a Large Chain Ring to Sprocket combo on the FD-6500 or 5500 Doubles. It appears that on the FD-6503 or 5503 this trim is not availiable. This may be confirmed at the following link;

http://bike.shimano.com/Road/Ultegra/componenttemplate.asp?partnumber=ST-6510

Then check the Service Instruction for the Shift lever.

Also note that I have set up my driveline many times and different bikes and although I'm definitely no Pro I have never seen a Shimano Indexed setup without at least minimal chain rub on extreme gears. I cannot honestly say it's impossible but I just have'nt seen it, even our local Bike Shop can't do anything. No this doesn't mean the Gears aren't availiable just that they may be a bit noisy.

Good Luck !

I have both 5503 (2000) and 6503 (2001)
and the trim adjustments are there. Do not
believe all you read.

I have no problem with chain rub, even on
a triple on a bike with extremely short
chainstays (e.g., sharp angles). It is possible.

- rick -

 

[Snarl]

Well there you go jgugelm, I stand corrected. I will endeavor to tune my bikes to the point there is no chain rub over the next week by starting from scratch and if succesful I will post results to this thread.

 

[Snarl]

Well I've re-set up my wifes bike and mine from scratch and this is the best I've been able to do;

My Ultegra Double Chain Ring
I have been able to get all 18 Gears without chain rub using the Trim in my Shimano Shifters most of the time. Needs a little tweaking after a few rides as it starts to rub slightly but as indicated above it is possible.

My Wifes Ultegra Triple Chain Ring
I have been able to get all nine Gears from the middle chainring, and 8 each on the inner and outer though the ninth gear has minimal rub on both. This utilizes the Trim adjustment in the Shimano Shifters however the Trim is not as positive as on my double and sometimes take multiple tries. I find the trim on the Triple shifters is harder to "feel" than on my Double. So regretfully I am unable to get all gears withour rub although I admit that it may be possible with a lot of fussing and constant tuning.

I will add that the extreme most gears, even if not exhibiting chain rub, do have a large angle between the chain and chainrings/sprockets and as such I feel riding ln these gears for any length of time has the potential to be hard on your components.

 

[rickwarner]

Originally posted by Snarl
Well I've re-set up my wifes bike and mine from scratch and this is the best I've been able to do;

My Ultegra Double Chain Ring
I have been able to get all 18 Gears without chain rub using the Trim in my Shimano Shifters most of the time. Needs a little tweaking after a few rides as it starts to rub slightly but as indicated above it is possible.

My Wifes Ultegra Triple Chain Ring
I have been able to get all nine Gears from the middle chainring, and 8 each on the inner and outer though the ninth gear has minimal rub on both. This utilizes the Trim adjustment in the Shimano Shifters however the Trim is not as positive as on my double and sometimes take multiple tries. I find the trim on the Triple shifters is harder to "feel" than on my Double. So regretfully I am unable to get all gears withour rub although I admit that it may be possible with a lot of fussing and constant tuning.

I will add that the extreme most gears, even if not exhibiting chain rub, do have a large angle between the chain and chainrings/sprockets and as such I feel riding ln these gears for any length of time has the potential to be hard on your components.

Starting at the bottom, what do you
consider a length of time that would
cause issues? I have many thousands of miles on triples with extreme angles,
esp. on a bike that has very short
chain stays. I do not notice any extra
wear.

On your double, the extra need for adjustment after riding a while is likely the need to adjust tension on the cable.
Do you have a barrel adjuster? Did you try just taking up cable slack a notch or
so?

On the triple cable tension is very critical. My bike with very short stays has no barrel adjuster, or place to put
one. I just added an in-line adjuster
and that has made fine tuning a
cinch.

The only time I have found the trim
adjustments on my Ultegra (6503)
shifters finicky is when the cable tension was too taught.

In other words, my experience is that
cable tension to the front derailleur is
the key to getting a smooth, and rub-free, triple setup.

- rick

 

[scituatejohn]

I have a double 105 crank with a double 105 front derailleur. I find that I can use the intermediate clicks to prevent the chain from rubbing against the front derailleur. When I use the small chainring with the small cog, the chain rubs against the large chainring, but not the front derailleur. I don't use that gear anyway, so I don’t let it bother me.

 

[Snarl]

Good points on the Cable Tension rickwarner but I beleive mine is "A" Okay, I have confirmed this through Park Tools Site, Shimano's Tech Information, and a Hayne Cycle repair Manual. As to if the 6503 Shifters have a finicky Trim position, mine do, at least when compared to my Ultegra double. Regarding the extreme chain angles and wear, I have no distance/time stats so I can not prove my statement. I am by trade a mechanic (Automotive) and currently work at an engineering firm. Based on my understanding of driveline angles and power transfer as well as come questions put to a PEng, it is my belief that constant running at the extreme angles will stress the sprocket/chainring teeth more than other straight driveline angles and result in increased wear. I have no stats to support my statement beyond what I have said.

I'm learning lot's during this thread keep 'em coming !!

 

[ibike]

Originally posted by jgugelm
My new bike has Ultegra Triple up front and I am getting quite a bit of chain rub when I'm in the small (granny) ring up front. I can hit the 4 biggest cogs in back without any rub but if I go past that it gets pretty bad. I went back to the shop and the tech hit the L limit screw with some minor adjustments and said it was fixed. After test riding in the parking lot and noticing no difference I went back and asked him to try again. He did and told me it was fixed but that I should never shift past the 4th or 5th smallest cog in the back. That effectively means I only have 4 or 5 gears available when I'm in the small cog.

Now I know I'm not supposed to cross-shift (small-small/big-big) but I would hope I could get at least 5-7 of the cogs in the back when I'm in the smallest ring up front. The big ring only rubs on about 2 of the big cogs in back. I'm willing to live with a 23 speed bike on a 27 speed drivetrain ... but 19, or worse 17? Does this seem reasonable?

I left thinking I'd either live with it or take it back when a tech. who seemed more interested in helping me was around.

So .... my ?'s are:

1) How many cogs should I be able to shift into without chain rub (while in the small or big rings up front?)

2) Anyone have any guidance on fixing this on my own. I'm reasonably competent around a MTB drivetrain and am assuming the road isn't that much different.

Thanks!

I don’t seem to understand your need to use all the gear ration options available. There is so much redundancy in rations that really makes it unnecessary to have to use all of the extreme cross shifting. Once you get past the 4th or 5th cogs while on the small chainring it would behoove you to shift into the middle chainring and the largest cog. Not only are there similar rations above the 4th or 5th cog-small chainring combination but the reduced friction efficiency offered by shifting up to the middle cog would only improve the effective ratio (versus what the perceived ration of the cross chain would offer).

If you’ve never calculated your gear rations, and to see what I mean, go here: http://www.bikeschool.com/ and create your own custom gear chart. If you can’t get the page directly then on the left side of the page, under “Entertainment”, select “Gear Calc”.

You will be amazed at how much repetition in ratios you have. Good luck!

 

[tourdelivermore]

I originally posted this in October...

I set up my Ultegra triple and can reach all cogs from all rings without rub except the two largest cogs from the the big ring which I don't want anyway.

Position 1 - small ring
Position 2 - small ring +
Position 3 - middle ring -
Position 4 - middle ring
Position 5 - middle ring +
Position 6 - big ring

You get to the - and + positions with 'half clicks' from the shifter.

The internet has several good articles on how to set this up...that's where I learned the technique. I used this source from cyclingnews.com:

http://www.cyclingnews.com/tech/fix/?id=frontmech

 

[luceberg]

Its pretty generic across the board bikes get sold as 27 speed or 24speed or whatever and it is a bit misleading at least. I dont think its deliberate sales hype, just a way of expressing that there are 3rings at the front and 8 or 9 at the rear.
The thing is that its best not to use the extremes of large front to large back or small front to small back anyway as it puts too much strain on things, especially the chain.
Its nice if the middle ring will work across the whole range though or at least can be trimmed to do so.

Lucian Proctor