Spellscape

Hi all

Is there any way to use new 10 speed shimano MTB derailleur on old downtube shifter (was 6 speed)
I just want to use 8 speed -9 speed cassettes with it and to save my classic derailleur for thematic rides.
It seems that I don't have enough cable to pull for 1 more cog on back - I can do it by hand pulling cable and all mechanically working fine.

Bianchigirll 

Shifting into the largest cog probably won’t work because as soon you release tension on the cable it will likely shift back to the smaller cog.

Spellscape

yes I'm thinking about
ENE 11S SHIFTER | Diacompe

Bianchigirll 

I’m unfamiliar with this particular shifter but it seems to be styled after some Campagnolo shifters I have. The rear/right shifter looks to have a much larger barrel to wrap all that cable.

I thought you were trying to use and older pair of shifters.

ENE 11 DiaCompe

Spellscape

Yes but if they don't have enough cable pool - I can change them supposedly - also saving them for vintage rides.
Are old french brazed downtube shifters mounts same size as modern ones?

Moe Zhoost

[QUOTE=Spellscape;22658602]yes I'm thinking about
ENE 11S SHIFTER | Diacompe[/QUOTE
I wanted to use DT shifters when I converted and old Bianchi frame to an 11 sp rear. The Diacompe shifters seemed to be the only game in town. Unfortunately I could not find them anywhere at the time, so I went with a Shimano Dura-Ace bar-end shifter that works really well.

You may have some luck with one of the cable pull converters, like the Jtek Shiftmates.

jamesdak 

I can say for sure that the old Simplex shifters will cover up to an 11 speed cassette.

If you are just barely falling short with your current setup try running cable housing liner over the part of the shift cable passing over the barrel of the DT shifter. That gives you a tad more range.

Dylansbob 

microshift makes a barcon/thumbie that can be used on a DT boss.

Spellscape

I think they are old Simplex - not single markings on them

jamesdak 

This is an Ultegra 9 speed RD

These covered everything from 8 speed Shimano up to an 11 Campagnolo cassette as I changed gearing over the years

This frankenbuild ran everything from 8 to 11 speeds over the years I had it. Simplex shifters had plenty of pull.

Are you sure your cable tension is right and limit screws are not causing problems? When you are on the smallest gear in back is the DT shifter at the end of it's travel in the one direction? So that basically you are getting all the pull capability? If so they it must by pull ratio on the RD limiting you if you can physically cover the full range of the cassette. Would moving to the other side of the RD pinch bolt give you more pull per movement of the RD?

Spellscape

maybe because my derailleur is MTB SGS ? I think road ones have shorter pull

jdawginsc 

Do you mean the retro friction, James? That would be good info since I have somehow amassed three sets, though I will likely never go 11 speed.

repechage

Miya not the stub diameter so much as different threading and cable stop plate mounting

1simplexnut

Yes those grey painted plain old levers are most definately Simplex .

KCT1986

Yes, pre-11 speed road RD use shorter pull. Pre-10 speed MTB RD also use a shorter pull and should work better than a long pull 10 speed RD.

Spellscape

I think yes - tested with my kids bike SHIMANO ALTUS RD-M310


and all is working just fine - so ordered SHIMANO Alivio RD-T4000 - hope it will work fine

Retoocs

There's an easy solution. Take the inner liner out of some shifter cables housing. You'll need about 2". Side the liner into the shifter cable all the way up to the shifter. The liner will now sit in the cable groove on the shifter. This effectively increases the diameter letting you pull more cable.

Hondo6

Exactly. The folks at Velo Orange say it can pull 50+mm of cable. They also say they've tested it with Shimano 11-speed road, Shimano 10-speed Dynasys (mountain), and Sensah SRX and found it works with each.

Spellscape

Will they fit old french brazed downtube mounts?

Hondo6

Have no idea. Might want to ask the folks at Velo Orange.

Hondo6

To add some detail: per Bike Gremlin, other than 6-8 speed Dura Ace Shimano used the same pull ratio for all of their index-shift mountain and road derailleurs up to 9 speed - 1.7. That means 1mm of cable pull by the shifter resulted in 1.7mm of RD lateral cage movement. (6-8 speed Dura Ace used a slightly higher pull ratio of 1.9mm). Shimano 10-speed road also used a 1.7 pull ratio.

That changed with 10-speed mountain, which Shimano called Dynasys. That used a very different (by between 30 and 40 percent) pull ratio: 1.2. So Dynasys required substantially more cable pull per shift.

Shimano 11-speed road followed suit and also used a lower pull ratio, but that was 1.4 - not compatible with 10-speed mountain. (Tiagra 4700 and GRX also use this pull ratio.) And 11-speed mountain changed again - to a pull ratio of 1.1.

Haven't seen info about Shimano 12-speed.

icepick_trotsky 

You can also try alternate cable routing at the rear derailleur to change the pull, or use a device like a Wolftooth Tanpan to change the pull ratio to increase it. This YouTube clip shows it in action. They use it to get a rivendell silver shifter to work with a SRAM eagle 11 speed system:

Spellscape

New nonMTB deraileur solved everything.
Actually it was cheaper than buying new shifters