Converting singlespeed to internal 3-speed?
I’m currently commuting on a singlespeed freewheel. I’ve been loading weight into some newly attached panniers, and I’d also like to go on group rides without having to ride home and switch bikes. I don’t think there’s enough space for a small cassette and derailleur so I’d like to get an internal 3-speed hub. This seems like a pretty straightforward conversion, but what about compatibility? I have 32-hole rims, can I use a hub with more holes? Does the frame and hub spacing need to match exactly or is there some leeway?
Are there any glaring omissions I’m making?
Anonymous 06/04/2012 at 10:02pm #
If you haven’t already, I recommend reading through what Sheldon Brown has to say about internally geared hubs:
As far as spacing goes, if the over-locknut size is the same on your current wheel as the IGH wheel you plan to use, then you shouldn’t have any problems converting. If the spacing is slightly different, and you have a steel frame, you can bend the rear triangle to make the new wheel fit.
Concerning spoke count, I’m not sure what to tell you, but I’m sure someone with experience building a wheel can help.
What size wheel are you looking to build?
Do I remember correctly that you have the Trek Earl?
From my internet search it appears that it has 120mm rear spacing. Even though it is steel, it might be a stretch to fit a 3 speed hub (127mm) in there. Maybe consider the sturmey archer kickback 2 speed hub. I am not an authority on this… at all.
At any rate, you would almost definitely have to get new spokes so consider just building up a whole different wheel and you could swap ’em if you so choose.
oh, and chainline could be an issue with the current bottom bracket.
Anonymous 06/04/2012 at 10:59pm #
scroll down to the bottom of the list and there is a Shimano SG-3C41 with 120mm spacing. It uses a coaster brake, but I think you can find its rim brake counterpart if you search the internet enough.
The link I posted before about cold-setting says it can be done for up to 10-11 mm, but you are permanently changing the spacing of your rear dropouts. Maybe just do a search for “120mm internal gear hubs” and see what comes up.
The last issue I thought of: do you have vertical dropouts? If so, you will need to use a chain tensioner.
i have an old western flyer 3 speed internal but its messed up im kinda afraid of what it might cost to fix it probly more than the bike is worth its a 65 western flyer
Anonymous 06/05/2012 at 3:38am #
@bear: What brand/model is the rear hub? If it’s an old Shimano 3-speed, it’s probably garbage anyway, but if it’s an old Sturmey Archer 3-speed, it might be repairable without too much hassle.
Have you or anyone opened it up to check it out? It’s actually less complicated in there than you might think. If it hasn’t been opened it’s probably just solidified grease, may just need a good solvent cleaning. I worked on one recently that the grease looked and felt like peanut brittle, cleaned out, worked perfectly.
Sturmey Archer eminently worth trying to fix.
its wasent used from 1970 till i rode it last year it might just be grease it works fine in first gear but freewheels in 2nd or 3rd
Sturmey Archer SX3 is a 120mm 3-speed fixed hub, though you could just spin a freewheel on there.
The AW is a 3-speed with a 127mm O.L.D. which would work if your frame is steel.
You could also get the Nexus and just take the coaster brake arm off.
Anonymous 06/05/2012 at 9:49pm #
@bear: Glenn’s Complete Bicycle Manual will have detailed instructions on how to rebuild your hub, and Kraynick’s will likely have any parts you need to replace. I ride on a 1973 Sturmey Archer AW 3-speed hub. When I first got it, I made sure to open it up and clean it, because I wanted to be absolutely certain that I knew what was inside it (using the wrong lube can damage the hub).
We have about 2-3 copies of Glenn’s down at Free Ride. If you can bring your wheel down there on Thursday or Saturday, I could help you open it and inspect it.
It’s also worth noting that 90% of all shifting troubles with older SA hubs are caused by the cable and not the internals of the hub.
it may just be the cable cause the only way i can shift it is with a pair of pliers its really tight i was thinking of droping it off at a bike shop to get fixed maybee scholls in west view
@ bear, man take Sherman up on his offer, I’ll wager he knows what he’s doing.
wheres free ride located i work 12 noon till 9pm monday thru friday driving a bus in shadyside and east liberty
FreeRide is in the same building as Construction Junction, just off N Lexington by Penn Ave. [map]
You should test ride something with a 2 spd kickback before going that route, they can be a little annoying and require some getting-used-to.
Anonymous 06/06/2012 at 8:16pm #
Here’s the Free Ride Calendar. General Open Shop happens every Thursday from 6-10pm and Saturday 1-5pm. I plan to be there as a staffer on Saturday.
@bear: I’m going to assume it will take about 2 hours to teach you how to take service a SA 3-speed. If you can, show up closer to opening rather than closing time. If you can’t make it Saturday, Kraynick’s might be able to help you.
Since you mentioned the shifter cable, here is where you can order a new “universal” cable with the anchorage you need, or you can just order the anchorage ($4 instead of $14) use a regular shifting cable ($1), a file, and some elbow grease to make your own 3-speed cable. Assuming the shifter itself is okay, that may solve your problem.
You must be logged in to reply to this topic. Click here to login.