dddd

The housing lengths aren't going to be the main determinant of how well that a bike shifts.

But I usually have found that shorter is better, right up to the point where one end of the cable housing starts to deviate from the straight path of the adjuster axis or of one of the cable stop's axis.
Housing length is less critical though with the modern shift housing!

Use of grease is a no-no with modern, lined gear cable housing, unless the grease used is of a silicone formulation or a low-viscosity grease that is free of the typical metallic extreme-pressure additives that are found in normal bearing grease!
Better-quality housings will be pre-lubricated with such lubricant so with no additional lubrication requirement.
A lot of people use Tri-Flow lubricant (oil) and which is far from the worst choice as it is less viscous than grease.

Gear cable housing is designed to work in conjunction with gear-specific housing ferrules. Such ferrules always have an internal plastic face into which each of the sharp-cut ends of the housing wires can embed and thus permanently equalize their individual share of the housing's compressive load during the pre-stretch process.
Grinding the ends of gear/shift cable housing defeats the above design intent and worse, it invariably contaminates the clean interior of the housing liner with thousands of grit particles. Using cutting wheels may lead to the same outcome if the housing liner doesn't first melt itself shut from the heat generated by the cutting. Dremel-cutting housings is also very time-consuming and causes noxious odors, again from the heat.

seypat

Here's another option. If you like the feel of the stem shifters, put stem shifters on the other 2 bikes.

steelbikeguy

optimizing the cables and all is good advice... however, when I saw the description of "spongy", I got an image of just needing more lever movement to make the shift. If that really is the case, then I think the advice to tweak the "B" screw was good.

One of the things that allowed Shimano to make indexing work so well was to keep the upper derailleur pulley very close to the freewheel/cassette cogs. This would be a reason that the modern Shimano derailleur will shift faster and with less lever movement than the older derailleurs.

To give the older derailleurs credit, the chains of the era were stiffer laterally than the modern stuff, and didn't require as much lever movement to coax the chain onto the next cog. For that reason, it's much harder to get a 1970's derailleur to shift quickly like a modern derailleur can.

So give all of the suggestions a try, and see what happens. If things still aren't as good as hoped, then perhaps provide a more thorough description of the issue, and maybe even take a video?
Or.. adjust your expectations accordingly.
Back in the day, we were just happy to get the chain to move between cogs without a ton of delay and noise! (sorta kidding, but not that much)

Steve in Peoria

Chombi1 

Simplex Retrofriction shifters.......Once you try them, you might not ever bother with any other downtube friction shifting system.
I can honestly say that they .might be one of the best bicycle components that the French ever made.
Surpringly simple, if you understand how it works, but elegant engineering.
IMHO, Even the well crafted Japanese shifters already mentioned look and feel clunky in comparison.

canklecat

Shimano Light Action L-422 shifters are also very good. If I'm reading the exploded diagram correctly, it appears to be a retrofriction shifter like the Simplex. I tried them for a month or so on one road bike last summer or the summer before and really liked them. But I preferred my index downtown shifters so I'm saving the L-422 shifters for another project. (BTW, the proper name for the downtube shifter version might be the L-400. Googling around just now, apparently the L-422 was the same shifter permanently affixed to a stem mount clamp.)

Some indexed shifters have a friction mode, but it doesn't usually have the same feel as good friction-only shifters.

Ditto all the above suggestions:

• Shorten those loops around the rear derailleurs. Not too short, but shorter than the loops shown in those photos.
• Be sure you're using shifter cable housing (metal inner running parallel along the length of the housing, same direction as the cable itself), not coiled brake cable housing. While brake cable housing will work with friction shifters, it'll feel mushy as the coiled metal inner compresses -- and it might cause some ghost shifting as the compressed coil tries to uncompress. And brake cable housing will work poorly or not at all with some index shifting systems.
• Some friction shifters with micro-click detents aren't bad at all. The cheap SunRace SLM10 friction thumb shifters are remarkably good for being so cheap. The Shimano Ultegra bar-end shifters I have on one hybrid aren't bad in friction mode, with those micro-detent clicks.

BTW, my trick for smoother friction shifting, when shifting from smaller to larger cogs, is to stop pedaling for a split second while shifting. When I feel resistance against the larger cog, I resume pedaling, then trim the shifter as needed. Takes a little practice but works well. However that trick doesn't work shifting from larger to smaller cogs, which still requires a bit more practice and finesse. After awhile muscle memory kicks in and we instinctively know how far to move the shifter. But it's tricky when we ride different bikes with different friction shifting setups.

70sSanO

As mentioned the Simplex/Mavic Retrofriction are great. I used them for many years. Downside is that they are very expensive.

The Shimano L-422 are a poor man’s retrofriction; except they are spring loaded instead of plates. They are still pretty cheap in comparison.

I think the 422’s are stem mounted, but I modded them to fit downtube. I also took out the ratchet ring as I despise ratchet friction shifters. Since the lever spring offsets the derailleur spring, to some degree, they really have a light action, especially with the ratchet gone.

I have other standard Shimano/Suntour friction levers lying around, but I don’t think I could go back to them.

John

Darth Lefty 

Why not go for a real shifter?

SurferRosa

There's no reason for your derailleur housing to be that long.

P!N20

Lasso cattle?

Harold74

I watched a Park Tool video that made much of the principle of coming off of the cable end mounting points parallel with the orientation of the thing holding the cable ends. It sounds as though i may have been too cautious with that.

The housing is indeed wired parallel to the cable rather than the winding / culvert pipe stuff of the brake housing. That said, it is bargain Amazon stuff as I mentioned..

Relative to the high end cabling that I have on other bikes, this bargain stuff seems laterally stiffer and less supple. That was part of what.lead to the grand loops: it doesn't turn as sharply as the expensive stuff.

SJX426 

....adding resistance to movement (spongy?).

canklecat

I've used some cheap SunLite brake cable housing from Amazon that was a bit spongy at first but settled in nicely after using it awhile. I bought some decent Jagwire and Shimano housing to replace it but decided to save those for another bike since the SunLite was fine after the coiled brake cable housing compressed and settled in.

Yeah, some shifter cable housing is stiff and hard to form short loops, including the entry level Shimano stuff. On the plus side, the low end Shimano cable housing isn't bad at all for the money, and is pre-greased, with weather-resistant silicone rubber wipes inside the ferrules to protect the cables. So that inexpensive Shimano stuff lasts for years with normal use.

tricky 

@Harold74 A few questions for you.

Is there any slop in the derailleurs on the downtube shifter bikes? Either in the derailleur pivots, or the connection to the bike? You can swap the derailleur between bikes to help isolate the problem.

Is the slop just in the beginning of the shifter travel or all throughout? In my experience, slop caused by "squishy" cables is worse at the beginning of the lever travel.

cycleheimer

SunTour bar-end shifters. You will love them!

dddd

Ooh, yeah, I've taken a liking to those bar-end shifters together with modern shift housing, Cyclone GT derailers and a Uniglide 13-28t 6s freewheel.

I went the extra mile and removed the B-tension screw, then removed some metal from the screw boss to allow the derailer to move even closer to the 28t large cog.

It is really something how well this works, especially after I lined the bb cable guide trough with some housing liner tubing.

Harold74

That's my understanding as well.

Yes, it is.

They are square an encased in allow ferrules.

I believe so. I use one of those Park, third hand cable puller things and the cables are nicely taught at all derailleur positions.

Harold74

With regard to the Simplex Retrofrictions, I agree they look awesome. I expect that forcing myself to not buy them for all of my friction bikes in the future will be a constant struggle.

The Suntour bar end shifters look cool too. I've been contemplating somethings similar with Dia-Compe's bar end friction shifters as well. Two things keeping are keeping me from using that method on the bikes shown:

1) My Nishiki: currently set up with bullhorns and reverse brake levers to save cost. Just had that stuff laying around. I'd have to pour more money into the project than I'm comfortable with to switch to bar end shifting. The Nishiki is a dumpster rescue and wasn't such a fancy bike when it was new. I took it for a nice 40 min ride yesterday and it performed admirably however.

2) My wife's Miyata 210: gotta sell her on the idea first. Additionally, I feel like I need to see that bike betting ridden some more before I drop $100 on new shifters and some recabllng. Maybe.

Harold74

I'm pretty sure that's what's on the Miyata and I agree, they're pretty great.

I like the micro detents too. And that's good to know about the SLM10's. I'd been considering them for a project but was concerned about eh quality at the price point.

Thanks for sharing that, I'll give it a try. My situation might be a bit different in that I'm running new free wheels with modern ramps, pins, etc. So I don't need to over shift. I'm finding that I do quite well just by being patient with the shift. A slow lever move (about 1s), just enough to initiate the shift and no more, seems to get me where I need to be fairly reliably without the need for trimming. Granted, I'm not racing and I'm riding a course that I know intimately so there are few urgent shifting surprises.

70sSanO

While the loops are a bit beyond what I’d use, they have no bearing on a spongy feeling, unless they are gunked up… or just poorly made housings.

People are running longer housing runs than that on bar mounted index shifters for years without any issues and those need to be a lot more precise than friction. And the shifter/cable have no clue if the long housing run is close to the shifter or RD.

Using bad housing is a different question.

John

zandoval 

I don't know if this will help but the best feeling shifters I have used are #1 Simplex racheting shifter modified to fit the down tube, and #2 SunRace. And I am not exactly sure why, they just felt better. On the same bicycle without any changes to the deraileurs, they beat out Shimano, and Campy for feel and satisfaction...

RiddleOfSteel

One could take your title's question/offer and say that there are a number of perfectly happy and classy looking indexed DT shifters and that could improve your situation.

Sans facetiousness, I will heartily second or fourth a vote for Simplex Retrofrictions. The extra cable use (thanks to the smaller barrels) gives a lot more grace when 'finding' the center of a cog. I've shifted a 10-speed cassette with these shifters, and that extra range of angle helped a lot. The real party trick IMO is how good these levers feel to operate, and how perfectly they hold a position due to their design. I'll get out of the saddle or accelerate in the big ring, and any DT shifter I have needs to be quite tight so as to not have the FD ghost shift to the small ring. It's Retrofriction or nothing for me as far as friction shifting goes. Nothing is even close.

VintageSteelEU

I'd second that as a guess, that's an awful lot of cable. Though it seems to be the case with the first bike as well, so perhaps the whole thing is down to simply what you're used to. I.e. downtube shifters feel different because you're not used to them?

Harold74

I had the same observation: the first bike is the one that feels best even though it has an almost ridiculous amount of loop housing AND housing at the stem AND no end caps at the stem because there's no space for them. It's tough to do a meaningful statistical analysis with so few data ponts though.

I'm sure that the downtubes do feel different because I'm not used to them. I've now got four decent length rides with them though so I feel as though I'm getting used to them. And there is still a difference in my perception of quality. I'm loving the heck out of DT friction shifting, though, and might have to set up all of my bikes that way. It's uncanny how fast one gets good at something that seems so clumsy initially.

Harold74

With regard to the Simplex Retrofiction shifters,

1) Are they user serviceable? Or do they not really require servicing other than basic cleaning?

2) Is it reasonable to expect that they'd fit braze on mounts originally intended for Shimano shifters / cable stops? I'd not want to drop $200 CAD on a pair only to have compatibility issues.

Has anybody tried the shifters shown below? I might go this route given that I'm struggling to find clamp on retro frictions at a price point that appeals to me.

Diacompe ENE

Harold74

Can you elaborate on that? Or point me to more information? What issues does the grease cause? I've been putting Park polylube in based on recommendations that I got... I don't remember where. As you surely know, online recommendations for this stuff can be pretty inconsistent at times.

Where can one procure decent cable end caps? They only seem to be gettable online if one orders expensive shift kits to go along with the caps. Given my druthers, I'd like to just order a can of 50 kick ass ferrules and be done with it. Are the ferrules specific to the brand of the housing?