TrackSmart

Some advice?

The Front Derailleur of my wife's Trek 1.2 WSD doesn't seem to have enough capacity for the gearing it shipped with. Either that, or the FD just plain stinks (which it does). Let me explain:

When you ride in the MIDDLE chain ring, there is chain rub in 2-3 of the 8 gears. Regardless of how you adjust it. You can only choose whether you want the chain rub to happen in the lower or higher gears - so frustrating! The bike shop guys said this is "normal", you just have to shift out of the middle chain ring to access the other rear sprockets. That's preposterous. You shouldn't have cross-chaining in the middle chain ring. Especially not in 3 of 8 gears. I have no such problems on other bikes with triple setups.

This bike is fitted with all Shimano 2200 stuff (bottom of the barrel). That's fine for the occasional riding my wife does, but the chain rub thing has to be sorted out so it's not frustrating for her to ride.

What's the best course of action?

- Upgrade to Shimano Tiagra front derailleur? (will it work on this 8 speed bike)?
- Upgrade to 8-speed mountain bike front derailleur (will the brifters have the right cable pull)?

I would have gotten her a better specced bike, but she LOVED the look of this one and is in love with it. I just need to get the shifting figured out without springing for an entire new gruppo!

jasonrobo02

I agree that noise in 3 of 8 gears is below-par for the middle ring. You should be able to get that with 0 rub, or maybe rub in 1 gear. Have you been working on it, or have you been taking it to the LBS? The LBS boys seem like they are taking the easy way out by telling you that your problem is just the norm.

To prove a point to the LBS, if you have a different bike that has a triple crankset and doesn't grind in 3 gears, bring that it to them and ask them to fix it so that it's operating "normally" and will grind in 3 gears

reptilezs

when adjusted properly the chain should not rub the cage when in the mid front ring and biggest in the rear. it may or may not rub when in the smaller cogs in the back. shifters have a trim function for a reason.

TrackSmart

The bike shop boys did 3 adjustments for her that summer. She always came back with chain-rub in 2 to 3 middle-chain-ring combinations. I thought they were just being lazy, but I was away most of the summer so I couldn't help her. Once we were both in the same location again, I was amazed that there was no was to get the bike to shift through all of the gears without having significant chain rub in normal gear combinations. I could only "choose" which side I wanted to rub worse, the top or bottom end of the gear range.

It was almost as if the front derailleur was not designed for the capacity it had to deal with (50/39/30 crank, 12-26 8spd cassette). The FD cage was just too narrow to span the full range of shifts without rubbing in non-cross-chaining combinations. Maybe they put a double FD instead of a triple on it? Or maybe the chainline is messed up? Or maybe it's just a piece-of-crap part (below Sora level) and has low quality control standards.

I don't know, but hopefully you folks can offer advice. My other bikes are mountain bikes or old-school bikes with downtube shifters. This brifters business is new to me.

PS: The Shimano 2200 level shifters (below Sora) don't have a trim function!

Al1943

Shimano road triple front shifters have 4 main positions plus a trim position for the small chain ring. The middle 2 positions are for the middle chainring. With the chain on the extreme left side of the cassette or the extreme right side of the cassette the front deriller must be shifted to the corresponding left or right middle position to avoid chain rub.
It sounds as if your wife's bike is normal. My wife has owned 3 bike's with Shimano triples. This is the way they all work.

TrackSmart

From everything I've read, these low-level brifters (8 speed Shimano 2200) don't have trim. That didn't make it's way into the low end stuff until 9 speed Sora. This is a 2008 model, which has 8 speed drive train and just-below-Sora brifters.

If it's not the derailleur, but the brifters that are causing the chain rub, then this is going to be a much more expensive fix than I imagined...

Al1943

Check to see if there aren't 4 main positions. The first position is simply all of the cable out of the shifter. There should then be 3 clicks as the cable is reeled into the shifter. There my not be a trim position for the smallest chainring (don't really need it). It is not possible to access all of the cassette cogs on any Shimano road triple without trimming the front dérailleur to either the 2nd or 3rd main position.
All dérailleur positions are built into the shifters not the derailleurs.

TrackSmart

Is a better front derailleur a waste of time here? And are there any other suggestions? I'm at a bit of a loss here - it seems as if this particular gruppo was designed to allow chain rub! The cage is narrow and the brifters have no trim setting.

joejack951

Most likely the issue is super short chainstays. What size frame is your wife riding? The shorter the chainstay, the greater the chain angle needed to use the outer and inner cogs. If you really can't live with the rub, you might want to try a 9 speed chain. The narrower chain might make it possible to use another cog though it may create it's own set of shifting issues up front. worth a shot before you go upgrading everything else though.

joejack951

Most certainly yes.

You have somehow convinced yourself that every gear combination should be usable when that is not how the system was designed. MTBers live without trim even on the highest end groups available. Use the rubbing as a sign to shift to a different chainring where you will find the same exact gear with a few rear shifts.

JiveTurkey

Do not assume the LBS mechanic adjusted it 100% correctly. The FD could not be on straight or be too high or low. I'd disconnect the cable and set up the FD from the beginning.

TrackSmart

You are 100% right. I have expectations from a bike. I presume that in the *worst case* 6 of the 8 rear sprockets should be usable from the middle chain ring without rubbing (i.e. all except the smallest and largest). And in the best case (which includes every bike we've owned), I should be able to dial it in so that all of them will work when in the middle chain ring. I can get 5/8 on this one. A 6th with just minor rubbing in one gear.

All my wife knows is that on her ancient hybrid (15 years old, with bottom of the line stuff at the time) she can hit every gear without chain rub. Heck, she can even cross-chain the thing (though she doesn't do this when riding) and not have significant chain rub. And she asks me why her beautiful, new bike makes so much noise when she's shifting around in her middle chain ring. I don't have a good answer for this. I expect things to get better over time, not worse...

TrackSmart

You are probably right. And I think this is where I will need to go next... And if that fails, I guess she'll have to live with doing more shifting on the front derailleur than she's used to.

Asi

Also chain rub can be against the bigger chainring. I cannot access the last 3 smallest cogs (on 8speed) with my small chainring (on double 39-53), the chain rubs against the big chainring (I have friction shifters so no problem adjusting to avoid chainrub with the cage), but this is a different problem.

You could widen the cage of the FD with some washers but that might interfere with the actual shifting trough chainrings but a 1mm wider cage would not do any harm I guess. (I mean the washers between the screws that close the cage)

Or friction shifting or a brifter with trim.

Al1943

My wife's Trek is a WSD size 47 cm (short chainstays). She can access all 9 cassette cogs with the chain on any of the 3 chainrings with no chain rub. But this requires using all 4 shift positions, it cannot be done with only 3 positions.

zjk

small frame mighto be the problem. The shorter stays means that even though the same set up that would work on your bike might not work on your wife's. The shorter stays that are made to accommodate your wife's body also make the angles made my the chain greater than they would be on a larger framed bike. She will have to use the trim and be conscious of her gearing.

wunderkind

Don't be surprise at the incompetence of folks at LBS. Some back counter wrench monkeys are prolly high school kids.
DIY is your best bet. You should loosen the cable bolt and clamp bolt. Go watch bicycletutor.com

If your Trek doesn't come with service literature, this Shimano manual may help....

http://techdocs.shimano.com/media/te...9830625446.pdf

TrackSmart

Agreed. This definitely exacerbates the problem. But see comment below (no trim).


I appreciate you taking the time, but there's no trim on these shifters. It's the 2008 model with the Shimano 2200 series, 8spd shifters. It's a step below Sora. Shimano does not include a trim position (as you indicate with the "3 position" comment).

TrackSmart

Thanks for the manual/install guide! Definitely good to have a reference for where things are supposed to be lined up.

wunderkind

If trim means barrel adjuster, try locating it by the down tube.

Al1943

But how many clicks do you get if you start from the lowest position, derailleur closest to the frame?

joejack951

Just like Sora triple shifters, Shimano only included a trim position for the small chainring when using it with the smaller cogs (and only for the big ring for the double shifters). There is no trim for the middle or large chainrings (unlike higher groups). See the tech doc here:

http://bike.shimano.com/media/techdo...9830686309.pdf

Al1943

On the contrary, the trimming explanation shown on this document is the same same as for Ultegra or other groups. My wife's Ultegra works just like this. As I have explained in my other posts. Trimming for the middle and large ring is available by using the 2nd, 3rd, and 4th "main" positions. The document describes how to use the trimming feature for the smallest chainring.
Read my post #5 above.

joejack951

Shimano does some screwy things. For 9 speed Ultegra, Shimano's installation instructions claim that 9 speed Ultegra has a trim position for the big ring. They do not, and Shimano has a tech doc explaining that they don't: http://bike.shimano.com/publish/cont...20Function.pdf

For 10 speed Ultegra, the installation instructions correctly explain that there is a trim position for each of the chainrings: http://techdocs.shimano.com/media/te...9830616322.pdf

If you look closer at the tech doc I posted for the 2200 shifters, you'll see the separate box explaining the 2203 shifter operation which explains that there is only a trim position for the little ring. Have you used Sora or 2200?

TrackSmart

Just checked. Two clicks (to middle, to top). No seeming adjustment by moving the lever partway in the middle position.