Shimergo front mech options

[bealer]

I've just rebuilt my Croix De Fer after a long tour to Oz, and decided to go with a Shimergo setup. It's all done and fitted and everything works fine. For the record I have:

- Campagnolo Ergo's Centaur 10-speed (2011)
- Shimano XT Rear Mech Shadow 9sp M772 (Long Cage)
- Shimano Tiagra Triple Front Mech 9sp 4503
- Shimano Deore Chainset 9sp M590 26/36/48T

My problem is with the front mech. While it works and shifts reasonably well, it's too stiff for my liking. Also being a road mech, it sits in a bit more, so requires more clicks to get to the next chainring.

I've read around quite a few threads, but many are a good few years old, so part availability is different (ie a Suntour XC front mech which apparently works great). Anyway, does anyone have any suggestions what would work and is currently available? I've read about MTB front mechs working well and not being quite so stiff...? Or would I be better off with a Campag triple?

My bike

[CREPELLO]

If you can find a Campag triple, that will do the job. Otherwise the Shimano R4xx or an appropriate Shimano MTB mech should work, the cable pull being a fraction longer on these than the ergo-shifters will pull. In which case you may need to tweak the cable clamp (shorten) slightly.

[Brucey]

MTB mechs need more cable pull and therefore usually have a lighter action.

Part of the trouble with some road mechs is that when set close to the seat tube, the mechanical advantage on the front mech is rather small because the arm is almost vertical at the start of the stroke. One way of overcoming this is to make a little bracket or extension to bolt onto the arm, made so that there is more mechnical advantage at the start of the stroke.

I don't know about current Campy front mechs but when I measured cable pulls recently Campy ones were some of the ones with the highest cable tensions, as much as 17lbs at the start of the stroke IIRC.

hth

cheers

[steady eddy]

There is a big difference in the length of the operating arms on the campag mechs ( long arms easy pull) and the shimano road ones - which have shorter arms. I cant comment on the MB ones but check the length as this makes a difference. I couldn't get Campag levers to operate a Tiagra mech and got a cheap campag triple in a sale in stead. If you get one you need to fit it very close to the big chain ring as the capacity is right at the limit for the Deore chain set.

[PW]

That chainset has a nice 12T jump between outer and middle rings, so it'll take a current Shimano mtb front mech. It's chainsets with a 10T gap which need the road triple to avoid the inner cage plate hitting the middle ring. So stick an LX or similar on it and you shouldn't have a problem. For those with 10T gaps the road mech is the only way unless you change one of the rings. I like NOS Suntour, they'll shift anything.

[bealer]

Cool cheers guys. I've ordered a Shimano Deore front mech. I'll see how I get on with that and post back the results.

Aside from the stiff front mech shifting I found setting up Shimergo really easy. The XT Shadow mech worked straight off. I'm going to have a closer look to see how accurate and smooth the changes are, but riding it around it's been fine. Am loving the cheaper cost of the Campag shifters, and they're clean cable routing. They seem very comfortable too.

[Brucey]

two caveats to the Deore route;

1) total cable pull ergos might not pull enough (as noted above)

2) chainline; if the mech is a so called 'top swing' type it won't allow the inner cage plate closer to the seat tube than about 17mm, which might be a problem depending on the chainline you are running.

cheers

[PW]

Pre-2007 Ergos work a Deore type front mech perfectly, I don't think the newer ones are any different pull wise. The only way to change a chainline is a longer B/B axle.

[bealer]

Shimano Deore M591 front mech is on. It's far easier on the Ergo's than the Tiagra I had, and goes down one gear at a time (the Tigra would jump from top to bottom).

It's not perfect though, it'll need some time playing around with it, try a few hubbub style ways of mounting the cable to increase the pull. At the moment I get first click (stays on smallest), second click (middle), third click (middle), fourth (top). The trick will be getting the initial tension right otherwise I end up in between gears. So usable although not perfect as I'm getting a little cage rub.

[cycloret]

I'm no expert on Campag FDs but from 2007? didn't they introduced the QS (Quick Shift) modification? Since then FDs have a longer front link which reduces the force of the pull needed but increases the cable travel so you'll will need the matching QS levers.

Brucey, your figure of a 17lbs pull, was that for a Campag QS FD?

edited to clarify meaning

[CREPELLO]

You appear to have the latest Powershift varient, judging by the smaller number of clicks the shifter gives. That seems like quite a challenge to set up. Best way forward would appear to me to try and match the Deore mech to a Campag mech in amount of cable pull required.

A suggestion. If by trying to vary the clamp position of the cable, you find that the ideal position disects straight through the middle of the clamp bolt (a possibility), then reverse the bolt, so that the head fits where the nut goes in the actuation arm. Then mark the spot where the cable would pass through the bolt, carefully drill it out and clamp the cable with the nut. Small adjustments will be possible by rotating the bolt a little.

I will likely try this myself with a R443 mech in the near future as I'm not totally satisfied with the cage profile of Campag triple mech's when used with non standard chain rings.

[Brucey]

Brucey, your figure of a 17lbs pull, was that for a Campag QS FD?

-nothing that recent; it was at least ten years old that one. I have not yet identified it exactly in fact; a situation not aided by their interesting habit of not bothering to put any identifying marks of any kind on anything...which has latterly been replaced with a penchant for vague markings that... rub off....

cheers

[bealer]

It's a dual pull front mech which is something new to me. Also has a rivet instead of a screw on the cage (I know stops me bending the cage to fit the chain in but it's annoying). I've got a powerlink on the chain now so it's not a problem any more.

It definitely doesn't pull enough. Not even close actually. I've tried the cable in the regular position, and also a sort of hubbub position where it's wrapped over and around to give more leverage. I'll play with it some more and produce some photos/results.

The 2 clicks per ring isn't so bad. It means I can now, although not ideal, use every gear or each cog without rub! If it's on the smallest chainring, and smallest cassette ring, it rubs (which I would expect). Give it one click, it doesn't make middle, but moves the mech a bit to stop it rubbing on that combo.

It does however rub on the biggest chainring when on the smallest cassette ring, which it shouldn't. I should be able to correct that by increasing the cable tension when clamping the cable.

And yes it's a set of Powershift Centaur Ergo's

[CJ]

Pre-2007 Ergos work a Deore type front mech perfectly, I don't think the newer ones are any different pull wise.

The new Ergos DO pull more cable for the front mech and don't shift Shimano road mechs anymore. I tried using a pair of 2010 Veloce on my Tiagra triple which a) made this mech very stiff to shift, so stiff that the mech spring occasionally defeated the detents in the lever and ghost-shifted from outer back to middle and (b) caused the mech to move too far between clicks of the ratchet, so that the mech could not be trimmed for some positions, so the chain would rub either one side of the cage or the other.

Some post-2007 Ergos, apparently, don't shift some other Campag mechs all that well either and Campag sell this widget (Campag part no. FD-CE011, see p42 of this catalogue) to convert them. It like makes the arm longer, so the cable does not need to pull as hard on it and so the mech shifts less far for each click. Good news is that after a little bit of work with a needle file, this widget also fits a Shimano Tiagra mech, and when fitted it also solves the cable pull problems for that!

It actually works in exactly the same way as the rear mech cable path "Hubbub" modification by which a Shimano rear mech indexes 9-speed when operated by a Campag 10-speed Ergo. So now my Spa Ti Tourer has the same mod both ends! I've been riding this double-headed Shimergo system for half a year now, completely troublefree. A slightly longer widget would be better, would allow slightly finer trimming of the mech, but it works so well as it is that I've not got around to making an even better one yet.

RJC import the vital widget to UK, described here as an Ultra-Shift Front Mech Cable Plate, price £4.25.

[CJ]

The 2 clicks per ring isn't so bad. It means I can now, although not ideal, use every gear or each cog without rub!

I think you may be misunderstanding the design of the left hand Ergo. It is not suposed to index the front shift. Front indexing is something Campag played with in the noughties, giving rise to all the opportunities for incompatibility between mechs and shifters partially described in the catalogue I linked to above.

AFAIK all their current Ergos have reverted to a micro-ratchet front shift - but with a whole lot more cable pull than before. A micro-ratchet system should take three or four clicks per shift, one click either way to trim. Two clicks isn't enough clicks per shift. It'll mean you can't trim finely enough so you'll have that problem I described of chain rubs one side or the other.

I think you need to extend the mech arm some more, so it takes more clicks to shift, not fewer.