# Triban 3 chain rubbing?



## wealthysoup (8 May 2012)

Hi Everyone,

I got a triban 3 from decathlon last month and when i use the biggest crank at the front (highest geared) the chain rubs against the front derailleur when im in the highest 3 or 4 gears. I took it back since then and somebody else set the gearing up but im still having the same problem.

Is this a typical problem with a triple or does it change over time as the bike is ridden? Do I need to take it back again to try to get it sorted?

Thanks,

Ryan


----------



## stephen.rooke (8 May 2012)

no expert but have you tried adjusting the h and l screws slightly to allow the derailleur to move more, a 1/4 turn might be enough.


----------



## daSmirnov (8 May 2012)

This is pretty standard on a lot of set-ups. Generally you should avoid using those gears and shift up to a bigger ring instead.

You might be able to tweak it a bit. I've got mine setup so I've lost my top gear, but can stay on the larger ring in a lower range of more often used gears.


----------



## wealthysoup (8 May 2012)

Hi dasmirnov, sorry I got my front gears the wrong way round. This happens when im on the biggest ring at the front and the smallest 3 rings at the back.

Stephen, I tried that before but it made no difference (the cable wasnt loosening enough to let it clear the derailleur properly), I tried to fix this and couldn't get it right so took it back to decathlon and a guy there set it up again for me.


----------



## Rob500 (8 May 2012)

Hi Ryan.
When you went back to the shop did they not advise you to avoid using the small chainring with the cassette's highest gears?


----------



## wealthysoup (8 May 2012)

Hi Rob,

Think I just posted before you there. As I mentioned above this is using the biggest chainring with the highest gears (for some reason when im away from the bike I think that the smaller chainring at the front gears it higher)


----------



## daSmirnov (8 May 2012)

Yeah using the "extreme" gears, i.e. when the chain is most angled will cause noise as the chain rubs on the dérailleur cages. Bigger ring at the front and biggest cogs on the back will do this. And vice versa.


----------



## Rob500 (8 May 2012)

Hi Ryan. Yeah, I think I just posted right after you.

I wouldn't have a clue how to fix that. . My Defy is a triple but I've never had any trouble that way. There's a thing I can do called 'Trimming' when the chain is rubbing. Can you do that on the Triban? Not exactly sure what's actually going on but perhaps a more savvy CCer will explain what it is.


----------



## Edwards80 (8 May 2012)

Mine does do this occasionally but I have re-tensioned (if that is the right word) the cable on the FD and adjusted the limit screw and it has solved it. It really hates being cross-chained though as mentioned above.

Trimming does work on the 2300 groupset . . . but I'm not sure it's a 'feature', if that makes sense. You can give the lever a nudge and it will get rid of the noise in some instances.


----------



## Recycler (8 May 2012)

I've got a triple and rarely use the cross chain extremes when I'm on the large and small rings.

Most of the time I just use the top 4 or 5 gears on the big ring , the bottom 4 or 5 on the small ring, and most of the whole range on the centre ring. The gears which I don't use are more or less duplicated elsewhere on the gear set.

As I understand it the cross chain extremes just result in more chain wear.


----------



## Sellyb (8 May 2012)

I purchased my bike brand new, supposedly checked by the mechanics, but it starts rubbing when the small front chain ring meets the fourth largest rear chain ring. Surely numbers one or two would be more reasonable for it to start rubbing. I've seen these high & low limit screws and have tweaked them a bit but can't see the derailleur moving, so I've screwed them back to where they originally were. Why doesn't the derailleur move? Sorry but I've never adjusted a bike before. It's not happy at the other end of the spectrum either.


----------



## wealthysoup (8 May 2012)

Thanks Rob and Edwards. Tried the trimming technique you mentioned and it stops the rubbing in a couple of the gears but not the highest 2, presumably its a trip back to the bike shop to get this sorted? Recycler, I'm not crossing the chain.


----------



## Recycler (8 May 2012)

Sellyb said:


> I purchased my bike brand new, supposedly checked by the mechanics, but it starts rubbing when the small front chain ring meets the fourth largest rear chain ring. Surely numbers one or two would be more reasonable for it to start rubbing. I've seen these high & low limit screws and have tweaked them a bit but can't see the derailleur moving, so I've screwed them back to where they originally were. Why doesn't the derailleur move? Sorry but I've never adjusted a bike before. It's not happy at the other end of the spectrum either.


 
The high and low adjustments will only work when the chain is on the top or bottom sprocket.


----------



## Hacienda71 (8 May 2012)

You should not need to touch your limit screws. This is only required if your chain is dropping of the most extreme cogs and if set up correctly when the bike was bought will not have changed.


----------



## mcshroom (8 May 2012)

If it's a clamp on mech you may find it's not quite straight (slightly inward at the back). This could also cause that sort of rubbing


----------



## Alembicbassman (9 May 2012)

My 2300 Shifter on my Giant Defy has trim settings, just a small click to shift the mech enough to allow the chain to pass freely. I do not use small chainring small spocket or large chainring large sprocket. 2300 is entry level, my 105 Compact double is much slicker but then it's more than double the price of 2300. Horses for courses really.


----------



## subaqua (9 May 2012)

Hacienda71 said:


> You should not need to touch your limit screws. This is only required if your chain is dropping of the most extreme cogs and *if set up correctly when the bike was bought* will not have changed.


 

thats the crucial bit. I am a big fan of Decathlon and the guys there but the 2300 FD on my sport 1 rubbed ever so slightly when i rode it properly hard for the 1st time . I used the destructions on techdocs to set it up/tweak it and it has been perfect since


----------



## Sellyb (9 May 2012)

It was quite an expensive bike which is why I am not best pleased, otherwise I would have understood.


----------



## subaqua (9 May 2012)

Sellyb said:


> It was quite an expensive bike which is why I am not best pleased, otherwise I would have understood.


 

expensive bikes doesn't mean will be set up correctly. you would like to think so but not always the case.


----------



## wealthysoup (10 May 2012)

Think I got it sorted, had to increase the tension on the front derailleur cable. Pity about the weather now.


----------



## Jason Ramage (26 Aug 2012)

The smaller frame sizes 45 and 48 have different front derailleur that the rest of the frame sizes. I got a 48" frame and was getting the same problems with the low and high gears (all on correct coggs no big cogg to big cogg etc ). i was told that it is due to the front derailleur is smaller. Complained about this and they are going to swap it for the larger one on the bigger frames.


----------



## stephen.rooke (26 Aug 2012)

most tripple setups are going to run im certain gears, just have to set it up so it doesnt in the gears you use most. mines set so i can use the highest gears with no problems. its caused when the chain is at its most extreme angle


----------



## oldfatfool (26 Aug 2012)

Why would you want to run the largest chainring with the smallest 3 on the cassette?? Off the top of my head (IE not knowing what cassette you are running) only the 3 largest cassette rings won't duplicate the gearing available in the middle chainring.


----------



## MrJamie (26 Aug 2012)

I was going to say to try increasing the tension slightly, so that the derailleur moved a little further outwards. Im forever tweaking my gears like this, but you need to get it just right otherwise itll rub when in the larger rear sprockets and when youre in other chainrings.


----------



## Fab Foodie (26 Aug 2012)

Jason Ramage said:


> The smaller frame sizes 45 and 48 have different front derailleur that the rest of the frame sizes. I got a 48" frame and was getting the same problems with the low and high gears (all on correct coggs no big cogg to big cogg etc ). i was told that it is due to the front derailleur is smaller. Complained about this and they are going to swap it for the larger one on the bigger frames.


 That's good info, my Son's has the same problem and I just can't seem to get it set-up right.


----------



## Rob3rt (27 Aug 2012)

My girlfriends had the same issue, the front mech was mounted too high on the seat tube and no amount of adjustment would cure the issue.


----------



## stephen.rooke (27 Aug 2012)

I was aprahensive of whether the gearing would be any good on such a cheap bike but it works great for me


----------

