Sprocket @ Wheel, Coaster break issue

Deadend · #1 10-02-2009, 11:16 AM

I'm new to coaster brakes, by the time i was interested in suping up a bicycle, i was in the realm of bmx freewheels and MTB cartridge hubs.

Whats the deal with this thing? I've googled and followed the instructions found on these two sites :

Park Tool Website

Bicycle Coaster Brakes

I pulled the brake apart, but i did it backwards, and backed the break arm out first... anwyay when i reassemble, it all fits and goes together well, but the exception is that the axle is locked up ( when i turn the wheel, the axle itself spins with the wheel, instead of remaining in place)

The clutch, pads , all that stuff are in there right, but its like they are perma engaged

I'm just about over this thing and im about to say "f' it" and pull the brake pads out and have it act like a normal freewheel.

Any suggestions on what im doing wrong? Thanks!

**Bikeguy Joe** · #2 10-02-2009, 12:12 PM

I will come clean here- two summers ago I took apart a Huffy (wal-mart model 1999 or so) and even with the help of all the kings horses and all the kings men I could not get that sucka back together (right) again. It was doing what you have described.

I threw it into my dam, into the place where all bad things go and used another wheel.
I never did figure out what I was doing wrong, and have taken apart many before and after that.

You could take it to the "experts" at the bike shop, and for about 10-20 dollars gain a good piece of knowledge.

Deadend · #3 10-02-2009, 12:14 PM

pretty much what im planning on doing - im not sure its worth another 3hrs of struggling, was just curious if the result sounded familiar to anyone

**Bikeguy Joe** · #4 10-02-2009, 12:20 PM

Yeah, I am pretty sure I got SOMETHING in there backwards. I have only had that problem once.

I will say I am definitely NOT a wizard when it comes to bicycles.

Maybe take it apart, leave it overnight, then come back to it fresh and start re-assembly from scratch.

Deadend · #5 10-02-2009, 12:23 PM

the shenans were lastnight, i didnt notice the failure until AFTER i already had the drive sprocket from the kit on. So i have at least a 15min removal of that coming to me after work.

I'm going to say screw it and take the wheel into a bike shop and pick it up tomorrow, after 9hrs of work, im over screwing with this p.o.s coaster brake lol

Venice Motor Bikes · #6 10-02-2009, 01:28 PM

One of the wisest things I have ever read on this site is Bikeguy Joe's signature... "If it ain't broke, and you mess with it long enough, it will be."

As far as fixing your wheel... make sure you didn't accidentally tighten the axle when you tightened the lock nut onto the brake arm.
Make sure the bearings are all in the correct way.
The other thing to check is that you didn't install the little brake shoes backwards & that they are properly in the little lock slots to keep 'em straight...

Deadend · #7 10-02-2009, 01:56 PM

im also curious about this :

The coaster break has an arm which is used to actuate the brake. But yesterday after i had the sprocket on - it was pressing up against the brake side cup and there was no way the rectangle (which the brake arm fits against) is NOT rotating with the sprocket.

Does this sound right? Or how are you guys mounting the rear drive sprocket for the kits against a coaster brake?

heres a fast diagram on what im talking about :

* NOTE - the sprocket cut out is not large enough to allow the brake cap to slip through the sprocket

thanks in advance

Venice Motor Bikes · #8 10-02-2009, 05:38 PM

It sounds like you have a much larger hub than normal...
Trim the edge of the dust cap to clear the hole in the sprocket. Or make the hole in the sprocket bigger.

Also... The brake arm doesn't actuate the brake!! (pedaling backward does.) the brake arm mounts to the frame to keep it from turning during braking.

Deadend · #9 10-02-2009, 08:01 PM

Quote:

Originally Posted by VENICE BOY

It sounds like you have a much larger hub than normal...
Trim the edge of the dust cap to clear the hole in the sprocket. Or make the hole in the sprocket bigger.

Also... The brake arm doesn't actuate the brake!! (pedaling backward does.) the brake arm mounts to the frame to keep it from turning during braking.

Yepo !

I came to this conclusion about 5 hrs ago, and my assembly of the coaster is spot on

So the sprocket went to a local machine shop for some lathe work.

I had read about Manic Mechanic's conversion but my fear was sending away, waiting 2weeks ( 5business days + 3 - 5 days payment processing ) and having it come back still needing machine work

NOT a knock to their work or craftsmanship - its more like "i have that kind of luck" - because i have had that kind of luck with this whole f*cking build /roflmao

The Desert Fox ( as seen in the chop sub forum) is my first build.

Im starting to think im doing things the hard way

Kevlarr · #10 10-02-2009, 10:36 PM

I had kind of the same problem with the first Huffy cruiser I bought and it wasn't from Walmart but another local mega-store. No matter what I did I couldn't get the bike to reliably stop, I mean I could literally put all my weight on one pedal and it would just slow down but when I would go to pedal again it was like the brake was stuck and I'd have to force it forward. Messed with that thing for two hours before I just gave up, returned the bike and went to Walmart.
Even the one from Walmart didn't have great brakes but I didn't know better because the last bike I had with coaster brakes was a 20 BMX over 30 years ago. The best thing that happened was when the bearing race broke and I got a heavy duty wheel from the LBS for $43 only then did I find out what a good coaster brake felt like.