Viich

So, my main commuter is now a 3 speed. Got a downtube shifter for the 3 speed wheel I built up over the winter, and that's the solution to my second derailleur explosion on that bike.

Now THERE's your problem!



To be fair, the derailleur may well be fine, but I don't have another 'claw adaptor', and the whole rig never really worked right with the rear spread to 130 OLD. I also had the Sturmey Archer wheel burning a hole in my 'to be used' parts bin, and now I've got motivation to figure out why the 5sp Sprinter hub isn't working (they're both drum brake versions - I'm seeing an ability to switch here)

I'm really enjoying the hub so far - it's really not any less trouble, as the 1056 drivetrain wasn't any either, but I don't find any lack of gears for my use, and I actually enjoy that I'm using a more varied cadence. I'm considering using the bike as my winter bike - it's got enough clearance for the 35mm studded winters I use, and getting rid of one more bike WOULD be popular with my wife. I just sold my carbon fibre road bike to pay for a BMX race bike (kids just started racing, wanted me to join in), and with this conversion on the Bianchi I think I may look for a slightly better steel frame to build as more of a classic road bike, and keep this as my usual commuter. 2 bikes for road riding, one for BMX should be able to be defended. My other two bikes aren't together right now anyway - might as well sell them, they're not much use as backup bikes if I need a couple hours to put them together.

I routed the shift cable same as I would a DT shifter for a rear derailleur, it just comes across under the chainstay to meet the indicator chain instead of going to the cable stop - lots of clearance everywhere. I had been considering a pully mounted to the seat tube, but it shifts very sharply as it sits.

I'll snap some pictures tomorrow.

FiftySix

I'm looking forward to the photos.

I keep toying with the idea of a 3 speed hub of some sort. My usual test is to figure which gears on my 7 or 8 speed bikes simulate a 3 speed and ride it in those gears for a ride or two. It seems that if gear 3 were set for my usual cruising gear of 70" then I'd only need gears 2 and 3. Gear 1 would be all but useless to me.

It's nothing but flat here and the only hills are overpasses or wind, and I never ride up overpasses.

fietsbob

3 speed math: chain drive gear ratio is 2nd, 3rd is 4/3rds (1.33) of that , 1st is 3/4 (.75) of that 2nd.

(big '/, little x wheel diameter in inches )

[57.6 2nd ,76.6 3rd, 43.2 1st] (my 16' wheel Brompton 54:15)


[54 2nd, 71.8 3rd , 40.5 1st] (a 2:1 chain drive, 27" wheel)







....

Viich

The yellow thing kind of happened by accident - next tape job is likely yellow as well.


I like the Sturmey lever


Housingless is better. Looks a little funny coming out from behind the chainring


Used the plastic cable guide - works great. Was going to use a Sturmey pulley, but the retaining tab didn't line up and I was afraid of more issues.


Drum brake for future.

FiftySix

Looks like a great mod.

You helped put me over the edge towards a future project I want to undertake. That is take a single speed bike of some sort and put a 2-speed hub in it.

I ordered a SRAM Automatix through Bezo's company. Should have it in a couple weeks if all goes as planned. Although, I haven't come up with the bike yet. In this situation the Automatix is a 36 hole hub, seems like that reduces the wheel options a bit.

Viich

Many rims are available in a 36 - my hub is a 36, I got it already with the crappy black paint from eBay for $15 including shipping. Bought a cheap rim from Amazon, or 'Bezos' company' as you say, and added on some double-butted spokes and washers to the order I was putting in at BikeHubStore.com for some new road wheels. Built up really easy, although I wish now I'd spent more on the rim - An H plus Son achetype in polished, or a TB14, would look great on it and would be better. $70 USD for either H+Son, or at BHS compared to $28 CAD, but I'd be happier about it now.

I use Sheldon's Gear Calculator
I'm running 44t chainring and 18t cog with a 622x35 tire, giving me:

gear inches of :
18T: 20T
Low: 49.8 44.8
Middle: 66.4 59.8
High: 88.5 79.7

As I had it built before, I had cross cranks on it with a 12-25. The highest gear I used regularly was 48:15, almost the same as 3rd, and 1st maps exactly to 38:21. As far as absolute range, I'm losing 2 gears off each end - I used the low ones slightly more often, but I don't really need them, it was mostly while biking with my kids. Basically, I'm losing the small steps. I actually like that it's making me use more varied cadence. I probably could go up to the 20T as I show above, but I think it would leave me in high most of the time instead of middle - I'd rather be in the direct drive, I think. I still use the high on most rides, so not a waste. I'm also planning on switching to a 30 or 32 tire, which will gear me down (very) slightly.

Old 8sp 48-38 x 12-25

48t 38t
12 108.7 86.0
13 100.3 79.4
15 86.9 68.8
17 76.7 60.7
19 68.6 54.3
21 62.1 49.2
23 56.7 44.9
25 52.2 41.3

FiftySix

Dang. Lost my post in a glitch.

I'm kinda hoping to find a bike with a set of 36H wheels already on it. Something like the SE Bikes Lager has 36s on it, per their specs. Most everything else I come across has 32H hubs.

However, I'll probably end up getting a 36H rim like you did to match the hub. That should open up my bike options.

By the way, I don't think I see many 3-speed drop bar bikes out there, which makes that Bianchi a unique ride. Too cool.

Viich

Thanks for the originality credit, but I think there're a bunch of them out there. Even if most people using 3 speeds aren't doing drops, there's a solid enough market that there are downtube and bar end shifters available.

There isn't really much point in taking apart a single speed wheel to put the 2 speed hub on - the spoke length is going to be different, so you need different spokes, and it's really better to just start with a clean rim. If you want something cheap check out the local bike coop. Which I should have done instead of getting the cheapo single-wall.

I've got an SE Draft Lite frame I'm likely getting rid of - I had my 5 speed sprinter hub on it a few years ago, but when it wasn't shifting correctly I just put a single speed freewheel on it and kept riding it for the winter. I'll work on getting the 5 speed working again so I have an easy-swap backup for the 3 speed (or vice versa)

noglider 

@Phamilton, take note.

Viich

I feel like a celebrity.

davei1980

Awesome job - is the shifter a bar end shifter mounted on the DT? If so, would "standard" DT shifters work in this application?

Viich

Sort of - I'm pretty sure it's the same shifter Sturmey-Archer sells as a thumb shifter, bar end shifter, or the under-seat shifter, but without a clamp or pod.

Having the Sturmey-Archer detents is terrific, the shifting is very positive. Plenty of people have said they've done it, and as long as you get into the right range (I think it's pretty forgiving), the hub should work fine. Issue is that running it in between gears is bad. 3 speed you can likely get away with it.

Phamilton

I've been wanting a 3 speed drop bar bike for several years and MAY take the plunge with my current commuter/all around bike, my Schwinn Voyageur.

Gresp15C

Nice build! A three-speed on a nice slick bike is a joy to ride.

I have but one minor quibble, based on a similar build. The shift cable running directly from the bottom bracket to the hub, leaves a lot of cable exposed to get hung up on things. My cable got caught on the heel of my shoe, and got torn out while I was on a ride. I had to hobble home in 3rd gear. So I now add a little guide -- here you can see that it's just a piece of cable housing, innertube rubber, and zip tie. This has lasted for a few years so far. Also, make sure the shift cable can't get hung up on the cable guide that's down there for the original derailleur cable.

Archwhorides 

Great thread! Cool mods!

Viich

May just be how I position my feet, shorter crankarms or longer chainstays, or some combination thereof, but I'm no-where close to the shift cable (or the chainstay) at any point in my pedal stroke.

I see you aren't using a cable stop on that end of the housing - do you have any issues with having to adjust the shifting?

Phamilton

I used to read this blog, before I joined BF. It’s no longer updated, and I don’t know the etiquette of publicly sharing the link but it’s still open.

Its what inspired me to ever want a drop bar 3 speed. My first bike as an adult was my Schwinn Collegiate. Not suitable for drop bar. And I don’t care for the Shimano hub.

3-Speed Blog and Occasional Keyboard Shortcut Trading Post

Gresp15C

Indeed, there's no cable stop there. I had to puzzle through this myself before I was satisfied that it's OK. The reason is that there's another cable stop in the system. The little piece of cable that you see is open on both ends, and just runs along the chainstay. So it's like just a guide for an otherwise bare cable. Then the bare cable goes through the plastic guide on the bottom bracket and heads up towards a cable stop that's attached where the downtube shifters were located on the original frame. From there, it goes through a regular housing up to the trigger shifter, which is attached to the stem.

On another 3-speed in my fleet, the shift cable is housed all the way from the shifter down, and runs along the seat stay. In that case, a cable stop is definitely necessary. I suppose a rule of thumb is that there are always an even number of cable stops in the system, where the shifter is one of the cable stops.

GamblerGORD53

Neato bikes, have fun riding without hearing grinding. ha But shift cables on the chain stay is really lame, IMO. Cable getting bonked or muddy beside your heel? Pffft
I'll ride in tall rubber boots now and then.

All my IGH attempts have had the shifter on the TT, including my Rohloff. I just sawed up some tubes and got them welded at Midas. Didn't get around to doing something prettier than hose clamps. My housings go all the way.

rudypyatt

I have a Windsor TimeLine setup with an SRF 3. On mine, I have the traditional trigger shift on the drop below the right brake lever.
The shop routed the cable along the chain stay. A cable cover, the wedge shape, came with the hub.



From today’s ride to Canarsie Pier in Brooklyn.

Viich

Nice bike Rudy. Do find the shifter in the way at all when you're in the drops? I like downtube shifting just fine for derailleur bikes as well, it's more my preference.

rudypyatt

I find that it doesn’t get in the way, though I do ride on the hoods more than the drops. I find it easy to shift and brake from either position.

My other bike, a Linus Gaston 3, has the same hub but with the downtube shifter.

RubeRad

Nice guide, but what's the point of the innertube rubber?

Gresp15C

Just to keep the thing from sliding along the chainstay.

pakman3999

Thats a reall cool idea