Front derailleur travel Microshift vs Apex

[drossall]

My son has a Boardman CX Team 2014. It's fine, but keeping the front derailleur adjusted has never been easy (and I've been fiddling with the things for 40 years). That bike has a Microshift front, though the rear and the levers are SRAM Apex 10 speeds.

I've now taken a good look, and my impression is that the outward travel of the mechanism is just not quite sufficient, even with (obviously) the limit screws backed fully off. One option is to swap it out, the obvious candidate being the Apex. I've never come across travel being an issue, but can anyone hold out hope that we might get that extra mm or two that we need by following this plan? The alternative is going to be bending the inner cage plate, I think.

[Brucey]

If the bike has a HT-II type 'road' BB you can often get a small change in chainline by fitting an MTB-type RH cup (which is a little over 1mm narrower) in place of a 'road' version and then using spacers on the left side to bring the assembly to the correct width.

Failing that it is possible that you are (unavoidably) running something close to an MTB chainline, in which case a 'road' FD won't always reach.  There are various workarounds for this, eg offset BO mounts and eccentric shims and so forth.

BTW there is a fundamental problem with many FDs, in that the shift ratio varies through the stroke; this can lead to 'trim clicks' not working properly and so forth, if the FD is mounted oddly (eg on a fat tube) or the chainline or cable run are a bit odd. This (despite a two-position option to keep the shift ratio within limits) caused so much trouble in first gen 11s kit that  the latest shimano road FDs have been redesigned to include a clever arrangement that separates the cage and arm movement so that the FD will work correctly almost regardless of frame and chainline (within limits of course).

If you think you don't need the trim clicks on the inner chainring of a double, a simple solution is to use an MTB FD (with the correct cable pull and drop etc) and to mount the cable differently, e.g. the wrong side of the pinch bolt. This usually brings the shift ratio close to that of a road FD but the thing will be more likely to reach out to a wider chainline.

You can have hours of fun with this one.... 

cheers

[drossall]

I'll look forward to it

The thing we don't necessarily want, of course, is to buy all the possible combinations. The offset mount approach sounds as though it could work. Can you give me any pointers. My Google-fu has failed so far. We might try the Apex front mech for braze-on, on an offset mount, to replace the current bolt-on.

Although I've just found this thread which says that a straight swap to the Apex helps.

[Torslanda]

Of course it could just be that the MicroSith is absolute pants, wants throwing away and replacing with "anything" that uses the same pull ratio before you start out on a wild goose chase.

Rival, Apex, etc. will all just, you know, actually work...

[drossall]

Is that true of all Microshift? I've looked at their stuff and wondered about trying it, from time to time.

[Torslanda]

I bought some. The MTB mechs siezed, the road stuff was ok but definitely down market.

[Torslanda]

Shame on Boardman for saving maybe a whole £2.75 on the cost of the bike.

[Brucey]

the photo from your link looks like a band-on mech. If the seat tube isn't the largest size, then you can use an eccentric shim with a large size band-on mech to offset the mech to get the reach right. SJS (amongst others) sell eccentric shims for this purpose.

 You might be lucky and find that the mech is already shimmed concentrically to fit. If you want to trial the approach (or just DIY it), some plastic tube can be filed/ground to fit and small differences can be packed out with tape.

Not a big fan of the microshift stuff TBH, but AFAICT it works OK if you keep it lubed.

cheers

[drossall]

It's band-on and the tube is 34.9mm. I removed it in the process of trying to get it working, and there's no shim. As I understand it, that rules out that idea (which is a pity)?

On the strength of comments on Mcroshift here and in the thread I linked from elsewhere, we're going to try the Apex band-on mech that matches the rest of the set, while we can still get one (looks as though they are being end-of-stocked everywhere). Here's hoping! I'll report back.

[Torslanda]

Any Shimano road mech with the old style cable pull (-> 4600/5700/6700) will also do the job and don't rule out buying a braze on mech and a 34.9mm adapter.

Improvement will be immediate.

[Brucey]

It's band-on and the tube is 34.9mm. I removed it in the process of trying to get it working, and there's no shim. As I understand it, that rules out that idea (which is a pity)?

yup, there is no wriggle room in that scheme after all.   Like tors says, there is a lot to be said for a BO mech and an adaptor, not least because it allows you to use the same mech on another bike for cost of one adaptor if the seat tube is a different size.

I have a large box full of FDs, most of which I shall struggle to ever use....

cheers

[drossall]

Well we fitted an Apex bolt-on. It was still a pig to find a combination of settings where it shifted the chain to the big ring, didn't rub, and all the other usual stuff. However, I did it in the end, and it's held up for a weekend away in Wales, so hopefully the job's a good 'un.

Thanks all.