Facanh

I'm having a bit of trouble identifying this internal gear hub. It's something i've never seen before, there are two shifters, and a cable goes into both sides of the hub. When I shift with the right shifter there is a noticeable change in gear ratio, the left one feels like it's a very slight change. It has a kind of butchered (I think) shifter setup with stem mounted Sachs Huret 2x6 position shifters. I can't even figure out if the "right side" is supposed to be 3 speed or 2 speed.
Any ideas what kind of IGH this is? I see zero markings on it. It's on a KTM city bike from the ~80s. I'm trying to figure out how many speeds it supposed to have, and what kind of shifter setup it would have come originally. I worked on a lot of vintage bike but never seen an internal gear hub like this, so i'm hoping it will be easy to figure out what it is.
Here are some pics:

Bianchigirll 

Cool beans. When I first tried my hand at mountain biking one of the guys had a 5 speed hub like that.

I wonder if this is a 4 speed with a hi/lo?

one of coolest things about old bikes is weird stuff like this

100bikes

Based upon the shift wire linkages, it appears to be a Sturmey Archer 5 speed hub.

I have not seen many of these, and the hub shell is not common.

rusty

oneclick 

Sachs Pentasport.

Don't lose the axle nuts, as I recall the axle thread is a bit peculiar and they fit the best.

dedhed

Based on the cable connectors I'd say Sachs/SRAM "SPECTRO" hub. Looks like "Pentasport". A Sturmey would be marked, especially an old S5

​​​​​​https://sheldonbrown.com/sutherland/...pentasport.pdf

oneclick 

Further;
you have a twin pull-chain version, you will need a two-cable shifting arrangement. Sachs made two versions, here are ebay numbers:

374394138969

and

374241332864

However, you might investigate to see if the trick for the SA twin-cable five-speed hubs works -

get a three-speed shifter for the right side, and any old friction shifter for the left. In the SA hub, the left shifter makes the the right side low lower, and the high higher - and it is either tight or loose. I suspect the operation of the Sachs is similar.

(You'd need a Sachs three-speed trigger, not an SA as they pull different amounts.)

Facanh

It says Sachs Torpedo Schweinfurt on the arm that connects to the chainstay, I missed that somehow.

It does look like a Pentasport, thanks for the help! It looks like originally it had one shifter with 2 cables going into it, and I guess the shifter switched between actuating the hi/lo and 3 speed "side", giving you 5 gears in total?
I'm fairly sure the indexing on these shifters just doesn't match with the hub, it does feel like I can get a 3rd low gear on the right side, but the lever pops out of position. Wondering what other shifter setup I could use if I can't find an original Pentasport.

Lattz

Pentasport indeed as others pointed out. I had one earlier, mine was with a 1 arm 2 cables setup and now thinking that should be it. since you have to pull one side to release the other, I don't know how could that be done with a setup like yours.
I had the version on the left. Beside being ugly and heavy, it was a dream to ride on a city bike, but you are screwed if you need a tire change/repair and don't know the secret of how to setup the proper cable tension

The lever pops out of gear if one side is too tight. There are videos on how to set them up, but they start with "set the lever to fourth", which isn't meant on your dual-shifter.

jiangshi

https://phoenix.craigslist.org/wvl/bik/7561233699.html

Facanh

It's kind of a sin because this hub is so interesting, but i'm thinking about "converting" this bike to just a regular 3spd. The sole purpose of this bike is gonna be to get groceries. I found one Pentasport shifter locally, but the price of the shifter is more than what the bike is worth. I'm trying to keep this bike cheap in case it gets stolen. But I want it mechanically sound with everything working nicely. It's flat where I live so I don't really need extra low or high gears.



Would this shifter work with this hub? When I worked on vintage bikes we used those Torpedo shifters all the time, but I can't find them anymore. However I see these going for ~10 bucks new.

oneclick 

Sachs and Sturmey triggers have different amounts of cable pull per position, so no.

Facanh

It says it's compatible with SRAM T3 hubs (says T3 on the shifter), still no? I see that these old Torpedo levers are now sold as SRAM T3 levers as well. It's a Sturmey Slst3 lever.

Lattz

The Sachs Torpedo Pentasport became the SRAM P5, but be careful, not all 5speed levers are designed for this 2cable setup, as Sachs later (but still before the seelout) introduced the clickbox, the one-sided variant with single cable.

Dan Burkhart 

Sachs Pentasport 5 speed. Not a bad hub, but the plastic two cable shifter was not very robust and broke easily.
I rigged one with two friction shifters and it worked well. Once I located and marked the position of the right shifter for the direct (middle gear) I could reliably shift every time.
The right shifter shifts between underdrive, direct and overdrive, the left shifter shifts between the two sun gears that split the underdrive and overdrive ratios.
The sequence goes like this
1st both cables taut
2nd right cable taut left cable slack
3rd (direct) right cable center position left cable doesn't matter
4th both cables slack
5th right cable slack left cable taut.

John E

Cool. I friction-shifted a regular 3-speed Sturmey Archer AW Coaster hub using a Huret downtube lever. First is all the way down, second is just above first, very useful (particularly with a coaster brake) neutral is next, and third is all the way slack. Easy to learn, easy to shift, no problem.

Facanh

Wow, I thought when the left cable was taut that always made the gear ratio lower, and when it was loose it always made the gear ratio higher, but I just tried it and that's not the case!
I've been playing around and I think I might be able to make the setup work with this 1x5 positioned Sachs lever setup with new cables and proper adjustment. But the lever pull might be off. Also the left lever is indexed as well, but the lever has so much slop/play that it doesn't want to hold the cable taut enough.
Now that I can (sort of) get all the gear ratios, playing around with the levers is starting to become fun. 🙂

Dan Burkhart 

It helps to understand the function of the sun gears. In the underdrive mode, the power flow goes from the ring gear to the planet carrier and having the larger of the sun gears engaged makes the speed differential greater meaning you have a lower gear. In the overdrive mode, the power flow is reversed making the planet carrier the input and the ring gear the output. In this case, the larger speed differential means that engaging the larger sun gear makes for a faster gear.

Facanh

Thanks for the explanation. I'm not very knowledgeable when it comes to internal gear hubs. I don't think I've ever owned a bike with an IGH, and so far I think I serviced/disassembled one IGH ages ago.

Daarke01

Wondering, have anyone managed to transform this hub into a 1-shifter?
Meaning, can the left side be static somehow allowing for a different brand of 3-5 gear switch for example to be used for the PentaSport 5?

I hate the idea of pulling/loosening two sides of the hub, and I especially hate those old gear shifters. I prefer rotating gripshifters instead. So wondering if it's possible to only use one side of the hub?

clubman 

There's not a lot of love for twist shifters with most of the 3-speed crowd even though they're cool. I've worked on a bunch and always converted to the triggers when they fail. If you want 3 gears, an SA would be a safer, more reliable bet, imo.

Daarke01

Yes, that seems to be an American thing not much love at all for gripshifters sadly.. However for me it's a must, as a Northern European when winter comes around anything else constantly jams or freezes. For older Shimano 3CC hubs for example I've found that SRAM P5 gripshift works and that's what I always put in. Either way, I found myself having a spare Torpedo Pentasport 5 hub in good condition, but the shifter is no good since a plastic part of it broke. Instead of replacing it I would like to insert a gripshift. But I'm still wondering if there's a way to only use one side of the hub to shift gears. Like having the left side loose, or tight constantly in order to avoid needing 2 cables or 2 gripshifters for each side.

Was wondering if anyone here has more experience with this particular hub, and if that would work. Or is the 2-shifter configuration a must to get it working?