By bike · City and commuter
City bike parts for internal hubs, sorted by the hub stamped on your rear wheel.
City bike internal hub parts are where commuters get stuck: shifter cables, cog sizes, axle nuts, the little click box. We source parts for 3, 7 and 8 speed hubs, plus chains, tensioners, dynamo lights, city tyres and cables, and we check each one against the hub before we quote. Chains from $24, tyres from $22, both indicative.
- 3-speed hub
- 7-speed hub
- 8-speed hub
- 1/8 in single-speed chain
- Horizontal dropout tension
- Dynamo hub light
- 700x35c
Asked for most
The five commuter parts we quote every week.
Drive
Chain and cog
- 1/8 in chain for most hub bikes
- 3/32 in chain where the cog is narrow
- Hub cog, 16 to 23 teeth
- Snap ring for the cog
- Chain tensioner for vertical dropouts
Rolling
Tyres, tubes, fenders
- 700x35c to 700x40c city tyres
- Schrader or Presta, by rim drilling
- Full-length fenders, 45 to 50 mm
- Rear rack on dropout eyelets
- Kickstand by chainstay mount
Control
Cables and lights
- Hub shifter inner cable, 1.1 mm
- 4 mm shift housing with ferrules
- Brake cable, 1.5–1.6 mm
- Dynamo front and rear lights
- Grips for 22.2 mm bars
Internal hub gears
3, 7 and 8 speed hubs, and what wears on each.
An internal gear hub keeps the gears inside the shell, so the chain runs straight on one cog and lasts far longer than a derailleur chain. That doesn't mean nothing wears. The shifter cable stretches, the cog wears hooked, the axle nuts lose their washers, and the little cable pulley or click box at the hub gets knocked on bike racks.
Three-speed hubs are simple and forgiving. Seven and eight-speed hubs need the shifter adjusted to a mark, usually with the bike in a middle gear, and the cable needs to be fresh. Most "my hub slips in fourth" calls end with a new 1.1 mm inner cable and housing, not a new hub.
We don't sell rebuild kits for hub internals. Those are a workshop job with the right oil bath and the right manual. Cogs, cables, shifters, click boxes and axle hardware, yes.
| Hub | Chain | Parts we're asked for |
|---|---|---|
| 3-speed | 1/8 in | Shifter, cable, cog, axle nuts |
| 7-speed | 1/8 or 3/32 in | Click box, cable, cog, snap ring |
| 8-speed | 1/8 or 3/32 in | Cable pulley, shifter, cog, anti-rotation washers |
Chain width follows the cog. A narrow cog takes 3/32 in; most standard cogs take 1/8 in.
Photograph the hub shell where the model is stamped, and the cable end at the hub. Those two pictures tell us the hub and the click mechanism.
Chain tension
No derailleur means you set chain tension yourself.
On a hub-gear bike there's nothing taking up slack. Tension comes from where the axle sits. Horizontal dropouts or track ends let you slide the wheel back; aim for about 12 mm of up-and-down play at the midpoint of the lower run. Tighter than that and the hub bearings drag. Looser and the chain drops off on a pothole.
Vertical dropouts are the awkward case. The wheel can't move, so you need either the exact link count or a spring tensioner bolted to the derailleur hanger. We size the chain from your numbers on the chain calculator in single-speed mode, which drops the +1 and rounds to an even link count.
- Slack at midpointabout 12 mm
- Horizontal dropoutslide the wheel
- Vertical dropouttensioner or exact length
- Link counteven, half-link if needed
- Chain wear limit, hub bike0.75%
Dynamo lights
A dynamo hub powers lights without batteries, and it decides which lights you can use. Most dynamo hubs put out 6 volts and 3 watts, and lights must be rated for that. Wiring runs from the hub tabs to the front light, then on to the rear. We quote dynamo lights only once we know the hub and the connector type. Battery lights are on the accessories page.
Process
How a commuter inquiry runs.
Photos first
Hub shell, rear dropout, cable end at the hub. Plus the tyre size off the sidewall.
We identify the hub and check each part
Chain width against the cog, cable against the click box, tyre against the frame and fenders.
One reply, one business day
That's the target, Monday to Friday. Indicative prices, held seven days.
Confirm, and it's bagged with its hardware
Snap rings, washers and ferrules ride along with the part they belong to.
Fair questions
Before you ask.
Can you convert my hub bike to derailleur gears?
Often not cleanly. Many city frames have no derailleur hanger. We'll tell you straight if it's worth it, and usually it isn't.
Do you repair the hub itself?
No. We're a parts desk. Hub internals go to a workshop. We'll send the external parts that workshop needs.
My chain keeps falling off.
Nine times out of ten it's tension, then a worn cog. Check the 12 mm slack first. Send a photo if that doesn't fix it.
City bike inquiry
Send your bike's details.
Hub model or a photo of it, tyre size, dropout type. We reply with the parts and the check run on each.
- Phone+1 (565) 555-2353
- Email[email protected]
- Desk68 Cedar Court, Office 12, Austin, Texas 28613