I have a Masi flat-bar road bike with Shimano 105 groupset (been in storage for years). I've disassembled the R440 rapid shifters and lubed them so that they rachet properly. However, the 9 speed pointer only travels one-third of the display. I assume that means that the internal travel is limited. What am I doing wrong?
There are several possibilities:
- Something in the optical display is assembled incorrectly. The way the Shimano flat bar displays work (or most of them) is that there's a little leg of the indicator (usually the red bit) that pokes into a notch of one of the internal parts that advances or returns as the gears are selected. Problems like you describe can happen if for example it's not in place in the notch but instead being pushed along by some other part. The display mechanism rides on the shifting mechanism, but the shifting mechanism doesn't care what the display is doing. If you can get all your gears despite what the display shows, this is probably what's happening, and the fix is to open up the top part of the shifter and put it together right. If something is broken, usually the only solution for older models is a replacement or donor. (Current or recent models have sometimes had replacement bits available).
- You could have succeeded in restoring the free movement of the ratchet pawls well enough that they work in the higher gear positions, but they're still moving too sluggish for the lower ones. As you press the thumb button to get into the lower gears (the greater cable pull gears), the return spring for the ratchet ring is winding up, which means it will spring back with greater force and speed than the lesser cable pull positions. The pawl springs need to outpace it and for that to happen their movement has to be very free. You can observe whether this is happening or not by shifting with the cover off. To improve it further, drip lube in each pawl pivot from both ends and then work it manually back and forth with a pokey tool. After you're done, wipe off the excess lube. When I do it I usually put a dot of grease on the pawl area or a very light coating of grease on the pawls because that's how new Shimano shifters come.
- If a pawl spring is broken outright, the same symptoms can also result for the same reason: the pawls aren't springing fast enough to keep up with the ratchet ring spring coming off the more wound-up positions. The pawl springs are tiny and are generally the easiest and most likely part of the shifter to fail. If a pawl is moving freely but with very little return action, i.e. floppy with a hint of springiness, this might be what's happening.
All of those conditions are the ones that actually come up on rapidfires in the wild under more or less normal storage/usage conditions. If you went extra far in taking it apart (i.e. more than just taking the covers off for for cleaning and lubricating the internal assembly) and you had some of the bigger springs out, I can imagine getting to a problem like you describe by simply not winding one or more of the springs up enough to get them tensioned properly to give you the full range of movement. Problems like that are what people are talking about when they advise against taking Shimano shifters all the way apart, because they can be a puzzle to put back together without the special tooling used to make them.