Phil_gretz

As a preface, I've read several of the RSX brifter threads where "blast it with wd40" and "soak it in warm oil, spin overhead, and wipe" advice teaches us how to get shifters to ratchet again.

My daughter's 1999 Bianchi Volpe has a different issue, and I'm wondering whether it's an internal mechanism problem, or may be related to something else... The drivetrain is full Shimano RSX 3x8 speed.

The upshift from the middle chainring to the largest ring is difficult to engage. It's what I would describe as "stiff". I'm able to make it shift with my hand strength, but my 22-year old daughter is not. The bike is extremely clean (fd, cables, brifters, bottom cable guide), so grime/grit isn't the apparent cause, but I have to admit that I haven't disassembled everything yet.

I've tried backing out the high limit screw on the fd a bit, just to permit a longer throw and maybe room (internally) to engage the final "click", but that doesn't have any affect. I'm thinking about a full disassembly, ultrasonic cleaning of the fd, replacement of the cable and housing, and treatment of the brifter to get maybe a bit of gunk out of that final click position.


So what do you think from your collective experience. Is a stiff final upshift click on an otherwise smooth brifter a sign of internal clogging, or something else potentially? Thanks in advance for thoughts. Phil

IthaDan 

Sounds like your cable is too tight, and despite loosening the limit, the fd is just out of range. Try twisting the barrel all the way in, or unclamping the cable and manipulating the shifter (while keeping tension on the cable).

Kimmo 

I'd suspect the shifter...

Does the frame have DT shifter bosses, and do you have a DT lever to test the derailleur?

Or it prolly makes more sense to come at it from the other angle; disconnect the cable, and holding it taut straight out of the shifter, run the shifter through its paces. If it's still stiff, it can only be the shifter.

Phil_gretz

Thanks for the common sense approach, Kimmo. I can try that very simply. It has DT bosses, so I could try a DT shifter on the left side, too. I'll start with the free cable (horizontal to the exit port) and actuating the shifter to see if it feels stiff going into the the highest position...

IthaDan 

It's the same ratchet pawl for the middle click as the top click when shifting. If it makes the middle click with no fuss, there's something adding tension to the shift into the top click.

Something like the physical limit of the FD.

LarDasse74

This sounds like the situation caused when the cable is routed incorrectly under the derailleur pinch bolt... THere is a little 'tab' on the washer under the pinch bolt, and the cable must be routed over this tab... if the cable is routed under the tab (which looks and seems very correct when installing the cable), the lever arm on which the cable is pulling is shorter and it greatly increases the force required for upshifting.

If you already have the cable routed over the tab then this is not the problem.

Phil_gretz

I'll check it. I didn't do the cable install myself (maybe previous owner or his LBS). The bike is somewhat new (to us). PG

Al1943

So have you tried the WD40?

Kimmo 

Guy asked me to look at his bike the other day, complaining of really tough front shifting; he mentioned a bunch of possibilities, but I only had to look at his bike for ten seconds to tell him this was his problem.

LarDasse74

I continue to frequent this site because it feels good being the first one to identify this problem

We will see how it turns out.

dddd

+1

I say it's either that, or some binding of the cable under the bb.

OP, if you're still on board here, have you lubed the cable down there?

Is the cable entirely in it's groove below the bottom bracket?

Phil_gretz

Thanks, everyone. I released the anchor bolt and let the cable run freely from the brifter...no resistance between upshift clicks. I looked at the height of the fd cage over the outer chainring when extended, and it was only 3mm or so. I prefer a bit more, so I loosened the clamp bolt and slid it up ~2mm or so. Inspected the bottom bracket guide (clean), and the cable slide through the upper housing (smooth). Then I carefully re-routed the cable over the little tab, pulled it firm, and tightened it. I also released the outer limit screw a 1/4 turn. Bingo! It shifts easily up and down. Thanks everyone for getting me oriented to do this right. Phil

dddd

Great.

As far as the cage height is concerned, the spec is for 1-3mm, and adding more can/will allow wedging the chain between the big ring and the cage or lose the chain to the high side, which can result in several possible derailer-damaging scenarios.

LarDasse74

+1. You have, hilariously, changed the one adjustment that may have been correct. The first adjustment you should make to a FD is to set it on the seat-tube so it is 1-3 mm above, and perfectly parallel with, the big ring.

dddd

And, I will add, that the measurement should be made with the outer cage plate as directly in line with the plane of the teeth as is practical.

Kimmo 

Yep, 5mm is way too much gap. Anyway, at least now you found the problem.

Phil_gretz

Okay. I'll re-lower the derailleur cage to 3mm. I appreciate the constructive feedback. PG

dddd

Of course, now you'll have to tighten the cable back up!

I always hate having to re-do perfectly good work, grrrr.