asbinder

So I mounted a new 3-Speed hub with a coaster brake on my daughter's bike (light kid on a heavy steel bike). The hub was difficult to fit in the dropouts but didn't require tools. I did have to manually pull the frame apart to get it started but that was it. Once mounted, the wheel turns much more sluggishly than I'd expected. To the main point though - The coaster brake is largely ineffective. I can get the bike to stop eventually but my daughter is going to have to stand on the pedal just to get any decent reaction at all. I've been all over the interwebs but must be entering the wrong search criteria; I only get responses regarding hub overhauls. This is (again) a brand new hub. Does anybody have any ideas for adjusting coaster brakes?

Been a couple of hours. I loosened the cone (only slightly) on the brake side. Not saying I know what I'm doing, but that's what I did. The wheel turns much easier now but the brake problem is unchanged.

fietsbob

Since I'm not there , seek out diagrams and exploded views .. maybe videos?

There is also the quality range, you may be at the low end of, Since a good, new, coaster brake Hub
like the Sturmey Archer S1C is about $55 on it's own.

[not currently a coaster brake user , myself]










...

asbinder

Ugh. The hub is a Sturmey Archer S-RC3 (II). Bought it new a couple of weeks ago.

Andrew R Stewart 

Cramming both the internal gearing and a brake into the same space that either usually uses means that both are generally reduced somewhat in size. Cut down the width of your brake pads and guess what happens to their performance?

I can't say much, from personal experience, on the current SA range of coaster braked IGHs but the classic S3C (and earlier TCW) had well known braking challenges. Andy

Dan Burkhart 

Older versions of SA coaster brake hubs, (pre NIG), were designed such that when third gear was engaged, the mechanical advantage of braking through the gear train in first and second was lost.
The NIG design activates the brake through the gear train in all three gears, so it has the same mechanical advantage.
That said, Sturmey Archer's coaster brake performance is less than stellar in my experience even with the new design.

dsbrantjr

Many bikes' forks are drilled to accept caliper brakes. Might be a good time to install one and get her accustomed to using hand brakes. Rear brakes of any sort are by nature limited in effectiveness; when the wheel skids that is all there is. Adding a front brake will be a vast improvement in stopping power.

andrewclaus

I agree on the front hand brake.

And when you loosened the cone, you probably put the bearings out of adjustment. Check for lateral play. If there's any perceptible, readjust to prevent damage.

asbinder

Thanks for the replies. When I first wrote this, I was concerned because I felt I was applying more pressure than I felt should be necessary to stop the bike. Maybe it's the weight difference (about a hundred pounds) but my daughter says this brake is just effective as the one that came on the bike. Watching her, I guess I have to admit she's right. I am considering a front brake, but we ride on pretty level ground so the jury's still out on that. She likes the cleaner looks of only one cable but we won't let that stand in the way of safety. Finally, about that cone adjustment. I get it, and the only reason I left it was because the hub wasn't turning freely at all before I adjusted it. I turned it maybe a 32nd of a rotation. I have no idea if that's enough to louse thing up, so if any of you think it is, please speak up. If there's another way of freeing up the hub without adjusting the cone, I'm game. Again, the dropouts were pretty snug, mostly when I tried to get the hub started in there (cheap bike, poorly aligned frame) but it the frame's too tight on it and that is a major cause for a stiff hub, I'll look in that direction. Just to keep the picture a little clearer, I tightened the outside nuts to spec. Thanks again for all of you taking the time to reply.

andrewclaus

If you can feel any play in the wheel when you try to move it sideways between stays, it's too loose.

Final cone adjustment is a matter of degrees, not fractions of turns. The end of the wrench often moves just a few millimeters.

The best adjustment has all bearings contacting the races all the way around, so it will have some friction. The upside is longer bearing life.

dsbrantjr

Cars pull out in front of bikes regardless of the terrain. I would not ride a bike with just one brake, especially just in back, but I am a belt-and-suspenders kind of guy.

dsbrantjr

Cars pull out in front of bikes regardless of the terrain. I would not ride a bike with just one brake, especially just in back, but I am a belt-and-suspenders kind of guy.

asbinder

Fortunately, I observed zero discernable lateral movement after adjustment. Believe me, if I had, I'd have put everything back. Sorry about the use of fractions. I moved the wrench, if I had to guess, about 6-8 degrees counterclockwise. I'm not sure how far around the arc the end of the wrench traveled; heck, I'm not sure how long the wrench is so I won't even start that math. I don't know the thread pitch either, so I'm not really sure how far I adjusted the race.

In the end, the hub spins well, and without any slop as far as I can tell, and my brake question has been answered well enough for my purposes. Thanks very much for your input.

fietsbob

...But I am a Belt-and-Braces kind of guy. (as they say, across the Pond)