Metaluna

As I understand it, the Wolftooth Tanpan is basically a Travel Agent that allows you to use Shimano 11 speed road brifters with Shimano 11 speed mountain rear derailleurs. As I also understand it, the Tiagra 4700 brifters have been tested and confirmed to use the same actuation ratio as Shimano 11 speed road. I think this means that, though it pulls more cable per shift, the 4700 rear shifter should also work with the Tanpan's pull ratio conversion. Why, then does Wolftooth explicitly say their gadget does not support Tiagra 4700? Has anyone here tried it?

https://www.wolftoothcomponents.com/...roducts/tanpan

HillRider

Tiagra 4700 is 10-speed, not 11-speed, so it doesn't work with 11-speed cassettes.

Metaluna

Oh, okay that's where my misunderstanding was. I guess since the Tanpan is designed to work with 11 speed mountain cassettes, then the cog spacing would be off if you tried to use a 10 speed road/mtn cassette.

PDKL45

That Tiagra groupset has a different pull ratio to other Shimano 10 speed road stuff; it is not cross compatible. There is an explanation that I can't remember off the top of my head, but if you Google "Tiagra 4700 compatibility issues" or something like that, you can find the reason.

Wolftooth is correct about the Tanpan; but you can use a Roadlink with Tiagra 4700.

Also, please note that there are 10 and 11 speed Tanpans, with and without inline adjusters. None of them will work with Tiagra 4700, I am afraid, but if you dig deeply into the Wolftooth website, you can get a good understanding of how their derailleur optimization devices work.

dsaul

Tiagra 4700 has the same pull as 11 speed road shifters and works with 11 speed road derailleurs to shift 10 cogs. I would think that the Tanpan would allow the use of 4700 shifters with an 11 speed mountain derailleur to also shift 10 cogs but gain the clutch feature of the mountain derailleur.

Metaluna

That was my reasoning as well. I think it all comes down to whether 11 speed mountain cassettes have the same cog spacing as 11-speed road cassettes, which, according to this article, they do not.

In other words, using numbers from the Art's Cyclery article linked above:

Shimano 11 road shifters pull 2.7mm of cable per shift.

This amount of cable pull moves a compatible road RD laterally by approximately 3.7mm -- the pitch of an 11 speed road cassette -- for an actuation ratio of approximately 3.7/2.7 = 1.4

The Tanpan takes that same 2.7mm of cable pull, and converts it to pull enough cable to shift an 11 speed mountain RD+cassette, which has a cog spacing of 3.90mm (pretty close to 10 speed spacing). Taking the Tanpan + Deore 11 RD system as a whole, this gives an effective actuation ratio of 3.9/2.7 = 1.44

Tiagra 4700, using an 11 speed road RD, must move the jockey wheels laterally by 3.95mm per cog, therefore must pull ~(3.95/1.4) = 2.82 mm per shift.

So you have a shifter pulling 2.8 linear mm per shift, acting through a lever of 1.44 lateral mm per linear mm. So a Tiagra 4700 would move the Deore RD + Tanpan combo by 2.82 * 1.44 = ~4.0 - 4.1 mm per shift. There is no Shimano road or mountain cassette, 10 or 11 speed, that matches this cog spacing.

Yeah, I know, there are a lot of roundoff errors here, and I carried way too many significant figures through the math in a few places. But it does look like, even though Shimano MTB 11 and Road 10 have nearly identical spacing, when the Tiagra cable pull gets reflected through the Tanpan, it has the effect of amplifying the small difference enough to make it a sketchy proposition.

Assuming my math is correct, of course.

Metaluna

I was looking at the Roadlink as an option as well (another option is a longer b-screw to clear the 12-36 cassette I'm trying to use). I'm a little nervous about making the RD hanger longer like that though. Wouldn't it make it easier to bend? I suppose it's no worse than with a mountain RD.

For full disclosure, I should mention that I also have SRAM Rival 10 with a GX mountain RD on another bike, which I could swap over. This would be an ideal solution (except for the amount of time an effort involved) and probably what I'll end up doing. I haven't had a lot of time to work on bikes lately though, so I was hoping to be lazy and avoid having to take two bikes out of commission and completely rebuild two drivetrains simultaneously.

dsaul

I take issue with Art's cassette spacing measurements. I have Shimano's framebuilder technical specs and it shows 3.55mm spacing for both road and mountain 11 speed cassettes. The only difference between the two is spacing of the largest cog from the freehub body. The mountain cassette has a recess that allows the first cog to sit 1.85mm further inboard, which also allows it to be used used on 9/10spd freehub bodies.

PDKL45

Hey OP, I just remembered that Velo Orange sell Dia-Compe 11 speed road or 10 speed Dynasys friction shifters.

https://velo-orange.com/collections/...1s-dt-shifters

This is kind of radical, but with those shifters (or just the right rear shifter) on a downtube mount, and using a 34-50 compact double Tiagra crankset, you could get a 10 speed Shimano XT (and maybe Deore?) trekking rear derailleur with a total capacity of 47 teeth to shift a 10 speed 11-40 or 11-42 Sunrace cassette.

You might need a Wolftooth roadlink or goatlink to get the derailleur down a little to get the top jockey wheel below the largest cog, though.

lennskii

Old thread - but thoght I'd post clarification (since the correct answer was never posted).

Yes, you can definitely use Tiagra 4700 shifters (which have the same as Shiano's 11sp road pull) with a Wolf Tooth Tanpan to convert your bike to a 1x10.

You just need to buy the 11 Speed Tanpan + an 11 MTB derailleur (e.g. M8000 XT or M7000 SLX) and a 10 speed MTB cassette (e.g. Deore M6000 or Sunrace CS-MX3).

The Tanpan convers 11sp Road Pull (Which is all Shimano 11 speed pull + 10 speed 4700 Tiagra) to 11 sp MTB pull ratio. Derailleurs don't have 'speeds', it is dictated by the shifter.

Wolf Tooth have confirmed the above in an email before I converted a Jamis Renegade Expat (Tiagra 4700) to a 1 x 10.