jwinsk

I have an old 6 speed, shimano 600 equipped bike, that's mostly original except the rear mech is a newer (8 or 9 speed era) 105. The bike has sat unused for most of its life so has really low mileage, so my only complaint is the downtube shifters. I am intrigued by the idea of shimergo, as outlined at this page: https://www.ctc.org.uk/desktopdefault...=3946#Shimergo

ergo 8 speed levers, or old 9 speed levers would work, but are getting harder to find and offer less of an upgrade path to more speeds in the future. ergo 10 speed levers would index right with my 6 speed freewheel if I got an old dura ace mech for the time being, and then I'd be able to have the frame spread at some point in the future and the same shifters would also index with an 8 or 9 speed cassette.

My main question so far is this: what about the extra four clicks? would the limit screws have enough range to dial these out? I've seen posts indicating that you can dial out the extra two clicks when using 10 speed shifters with an 8 speed cassette, but I worry that 4 extra clicks is too much.

Bianchigirll 

is your current setup indexed? unfortunately you can't just put the STI "Brifters on your bike. you can't use 8 or 9 speed shifters ona 6spd freewheel. the spacing between the cogs is different, so it not simply a matter of seting the limit screws. at a minimun you would need a new 8 or 9 spd rear wheel to match your new brifters.

the bike has sat unsed simply because of the shifters?

FBinNY 

If can get the right adapter to convert the pull ratio, then you're good to go. The limit screws are on the RD, so and should have enough range to do their job on a 6s cassette. But not, you you can sub a longer screw. As for the extra clicks, don't worry about them, you just don't use them. Set it up with them at the high end and use them to slacken the cable for service.
Just so you know, you'll be increasing the cable pulled, so it'll increase the force required. If you like light action shifting, this may work against you.

JiveTurkey

I think I understand what you're saying. You've found a way to index Campagnolo shifter to your 6-speed freewheel?

Well if it'll work, then it'll work. You'll need to set the limit screws as you mentioned. You can either lockout the 4 lowest or 4 highest gears. You can do either.

When you set things up, just put the shifter into whatever gear (shifter position) you want to use for the highest gear (smallest cog) with the chain on the smallest cog. Obviously, it will need to be shifter position 6 through 10, so that there are enough positions for the 5 lowest gears/largest cogs.

If you set the highest gear to be on shifter position #6, be aware that you'll still be able to upshift into 7-10, but the high limit screw won't let the rear derailleur move and so you'll just create slack.

If you decide to start in shifter position #10, then you will effectively lockout the 4 lowest shifter positions. If you try to shift into position 4, then you'll be fighting an unmovable cable. This could cause potential damage if you repeatedly and forcefully do this. (A similar issue developed for some people who locked out one of the shifter positions on their triple shifter while using a double crank).

HOWEVER, keep in mind that the brifters are the most expensive part of the drivetrain. If you're already going to get new shifters and you have a rear derailleur that will work with a modern drivetrain (if you stick to Shimano), you may want to consider just going all-out and upgrading. In your case you'd need a new rear hub/wheel, so that will increase the cost (but you'll have to pay for it eventually).

You can do the step-by-step approach, but you'll be buying an old Dura Ace RD that won't be used later on.

jwinsk

Yes, the current setup is indexed. I only guess that the bike sat unused for most of its life because when I bought it a few years ago, it appeared to have very few miles on it for a bike of that age. I've been riding it since.

I realize that the cog spacing is different, but according to the ctc page linked above, certain combinations of ergo levers and shimano freewheels or cassettes will work together because the "incorrect" cable pull accounts for the wrong cog spacing. When you throw an old dura-ace derailleur into the mix, which expects a different cable pull than other shimano mechs, you get even more possibilities. You can also trick the derailleur into working with other combinations through an alternate cable routing.

So apparently lots of possibilities, but since keeping the existing wheel seems cheapest for now, I was hoping someone could confirm whether 10 speed ergo levers would actually work in practice with a 6 speed freewheel and an old dura ace mech, or whether it's just noted in the table because the indexing works out, but is not really practical.

jwinsk

Thanks for the advice, and I'll definitely put some thought into whether to just stick with shimano and get the frame spread.


Thanks. Any idea where to find longer limit screws? I doubt my local hardware stores stock screws that small. Would that be the kind of think a bike shop would carry or is it too unusual of a request?

revolator

If you had a shimano 7 speed cassette hub wheel. You could put a shimano 10 speed (minus 1 cog), and run shimergo with campy 10 speed shifters with the 9 in the rear.

FastJake

I can't for sure that your idea will or won't work, but Sheldon ran Ergo shifters with a 6-speed freewheel on his Brown:

"Most recently, further in the spirit of breaking the rules, I installed a set of Campagnolo Veloce 10-speed Ergo shifter...still with the 30 year old Cyclone and the 6-speed Regina Oro freewheel...and that works too!"

https://sheldonbrown.org/brown/index.html (Scroll down to "Later Equipment Changes")

I agree. Brifters are very expensive, and if you're willing to shell out the cash for them you might as well get a new rear wheel too and run however many speeds you want (since your 105 RD can handle it.)

jwinsk

True that brifters, cables, and stops alone will be expensive, but I'd rather not have to shell out the extra all at once to have the frame spread and get a new wheel, cassette and chain too. Just an old dura-ace mech, although useless further down the road, seems a more managable solution until I really need to replace my rear wheel.

FastJake

Another thought: have you considered bar-end shifters? I put them on my downtube shifter bike to avoid buying brifters. You could get a Shimano Hyperglide 7-speed freewheel, 8 speed bar end shifters and (in my experience) you could get it to index pretty well. I don't think you'd have to spread your frame with the 7-speed freewheel.

Dave Mayer

You are correct. Campagnolo 10-speed Ergopower shifters pull the right amount of cable when used with an old (pre-1997) Dura-Ace rear derailleur to index correctly with a 6-speed Shimano HG or Uniglide cassette or freewheel.

Ignore the rest of the muddled and irrelevant postings here - the understanding of how index shifting works is limited to a very small number of cyclists; even only few shop mechanics understand the proper relationship between the shifter cable pull, the rear derailleur mechanical advantage and rear cog spacing.

The limit screws on the rear derailleur will lock out the 4 extra positions on the shifters. There are no negative effects. Make sure you do carefully adjust the limit screws to work with the 6-speed freewheel, as you don't want the derailleur jumping into the spokes.

Downsides:

Old Dura-Ace rear derailleurs were designed for racing cogsets. They handle a 26 tooth max cog. In my experience a Suntour Accushift mountain derailleur has the same mechanical advantage as old Dura-Ace. These will handle much bigger cogs.

Suggestion:

For a much cheaper and conventional approach to integrated brake/shift levers, buy some Shimano Sora 7 or 8-speed shifters, get a basic Shimano rear derailleur (not old Dura-Ace - almost anything else made in the last 25 years will do, including the Shimano MTB stuff), and change your 6-speed freewheel for 7-speed Shimano HG freewheel ($15). The width of the 8 and 7-speed freewheels is close. This way you will not have to do expensive overhaul/mods on your rear wheel.

Dave Mayer

Correction: I should have written that the width of 6 and 7-speed freewheels is close. Both fit in bikes that have 126mm stays.

NightShift

https://www.bikeforums.net/showthread...ity?highlight=

If DaveSSS is correct Campy and Shimano shifters have different cable pull across their range, and the action of their derailers varies across the range of motion. If this is true you may still be able to use 10 speed ergos with a 6 speed freewheel, but which six clicks you use would make a great deal of difference.

jwinsk

good to know

I was originally considering this approach, but was attracted to the veloce levers because they would neatly route the shifter cables under the tape and and would give me the 9 speed option further down the road. Maybe 7 for now and 8 later would be enough for this bike though, I will have to give it some thought.

jwinsk

I haven't really considered bar end shifters, but I guess it's an option. I think you're right about a 7 speed freewheel fitting my frame. I've considered several options involving a 7 speed freewheel, but they offer less future upgradability.

jwinsk

Didn't know that. Thanks.

jwinsk

Campy 10 speed shifters with shimano 10 speed spaced cogs isn't one of the combinations that works, although I did consider trying to find a 7 speed cassette hub wheel at one point and doing just what you mentioned with shimano 10 speed shifters. Didn't have much luck finding an old 126mm cassette hub wheel though.

revolator

- Yes I mistated, should be campy 10 speed, with Shimano 9 speed (w/one cog removed) 4.35 pull vs 4.34 pull (std shimano, not old dura ace)
- I had a brand new wheelset Shimano 7sp w/ campy Ofmega rims I gave away. You can try to ask if anyone on this site has a used one for cheap? The effort might negate itself, but any Shimano Mtb 7 speed cassette hub would work.

To throw in another cheaper option: Jagwire Barcon adapters https://www.amazon.com/s/ref=nb_sb_no...barcon&x=0&y=0
- convert the DT to barend shifters.

Kimmo

IIRC, Shimano shifters use different amounts of cable travel between different gears, unlike Campy.

Presumably Campy derailleurs have a much more linear relationship between cable pull and derailleur movement. I've noticed Sheldon can be a little slap-dash when it comes to the finer points of drivetrain compatibility...

Perhaps this setup can be tuned to work perfectly, but I wouldn't be surprised if the best you could manage is slightly sub-optimal.

Now that I've read the whole thread,

That would definitely matter, I'd say... it will prolly take some trial and error to get it working sweetly.

I'd consider rebuilding the wheel (keep the spokes if they're undamaged) around an 8spd freehub. If you're not a big guy, you can try doing it with more dish and space the hub to 128mm, if you really want to avoid re-setting your frame. If you are a big guy, re-setting it to 135mm would probably be a good move (although such a large change would almost certainly require tweaking the dropouts back to parallel).

IMO there's no good reason road bikes shouldn't have 135mm OLDs. A 2.5mm compromise in chainline versus the extra strength of the rear wheel you can spend on durability or a lighter rim is a no-brainer for me...

I wonder how close you could get spoke tensions with the right lacing, an OCR, and 135mm OLD...

fietsbob

Strip the gizzards out of the <C> levers, then they're just brake levers.

friction shifting elsewhere, bar end , down tube or 'Kelly take offs' to put downtube levers
inside of the brake levers..

with a little hand labor, any combination will work.

Kimmo

Ye gods man, there's no call for such heresy as losing the whole point of the Ergos.

Sheesh.

jwinsk

Apparently campy shifters do too:

If I can't get it to work well with my 6 speed freewheel though, I suppose I can take the plunge and go to an 8 speed or 9 speed shimano cassette hub. I'll consider a 135mm hub like you suggest, since I am a pretty big guy (190lbs), so I'd probably want my LBS to cold set the frame and check that the dropouts stay parallel.

fietsbob

Hey they <C>sell them that way, too, Carbon brake lever and all.
6 speed shifts so nicely without indexing , because of the space between cogs ..
Ultra 6 begat 7,8.. then 9,etc,

gear heads [shakes head]

FBinNY 

So does this kind of B/S spam actually generate business for the spammers?

Kimmo

How about a DDOS for your trouble, scumbag...

It also indexes beautifully, due to the space between cogs.

It occurs to me that Ergolevers are the only brifter that would lend themselves to be converted to friction...

Friction Ergos would be sweet! What compatibility drama?