Mounting sprocket on a bike with a coaster brake

heyscuba

heyscuba

New Member
I'm mounting a motor kit to an old 82 Murray Cruiser
and I'm starting with mounting the sprocket, but there's a coaster brake and I'm having a problem in this area,...
e-mail me if you can help,...
First off, the sprocket doesn't fit over the hub assembly,
I'm making the hole bigger now by slowly reaming it out with a Dremmel Tool,
but I fear once I get it to fit over that part IF I put that outer (thick) rubber washer on the wheel and then the sprocket on it will all stick out to far and I will not be able to put the coaster brake bracket into it's slot if supposed to fit into.
Please HELP!!!

A) do these kits work with coaster brake bikes?

B) do I absolutely need that outer rubber washer,...? or can I do without it or try to find something thinner?


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:-||
 
the coaster brake arm needs to be bent in a "Z" shape to clear the sprocket.

some people have run the sprocket without the rubber "rag joint" inbetween, but it's not recommended. if you have any movement, you could wear through your spokes, or weaken them enough to fail.

yours is a common problem, and yes, these work fine on coaster brake bikes, but there's always something that needs to be rigged, no matter what kinda bike it is.

use the search feature up top and you'll find tons of threads about the dreaded coaster brake problem and it's fixes.
 
thanks,...
the problem now seems to be the thickness of the sprocket even without gasket behind it, the part of the hub that sticks out on that side is not longer than the sprocket is thick, so the coaster brake bracket will be pressed against the sprocket which needs to spin,..?
also,... which way should the concave of the sprocket go,.. towards the wheel or away from it?
thanks again,....
 
usually, the nice shiny chrome side of the sprocket goes towards the spokes. depends on the chain clearance/alignment of your bike.

like i mentioned, you need to put your coaster brake arm in a vice and bend it like a "Z."

it should look more or less like this when you're done:

14646d1255658315-custom-coaster-brake-arm-arm-2.jpg
 
I can see where that will fix one aspect of my problem, I'll try to get you a picture of my specific problem.

thanks for chiming in,...
 
Here is what I mean,...

and this sprocket is pressed darn near right on the spokes (I put a very thin gasket inbtween) but the assembly of the hub is not sticking through the thickness of the sprocket



the only thing I can think of is to cut the center hole in the sprocket with a cutting torch in a huge circle (or grind down the outside of the bracket?) so the bracket will fit through the hole and up against the brake pad locking assembly.
(left edge of pic)

 
ok,... trying again with the pics,....

I'm trying to figure out how to get that coaster brake bracket to mounted securely up against the brake pad locking assembly,...
 

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Hmm... If you need to take more off the sprocket do so. But from your pick I can't tell if you need to or not. I do know that you will need to tighten all your bolts and that will help with the brake arm clearance. Also, it looks like the sprocket dish is pointing in. Is this where you will want it? I know on my coaster I had to have it facing out so my chain would not rub my big fat tire.
 
solokumba said:
Hmm... If you need to take more off the sprocket do so. But from your pick I can't tell if you need to or not. I do know that you will need to tighten all your bolts and that will help with the brake arm clearance. Also, it looks like the sprocket dish is pointing in. Is this where you will want it? I know on my coaster I had to have it facing out so my chain would not rub my big fat tire.
Click to expand...

yep he needs to turn it around i run mine against the pokes tighten it down very tight and it will be fine i also blue lock tight everything
 
think I got it,... thanks,...
but still wondering about a couple things,...
but how tight do you tighten the threaded (nut I guess?) piece with the dust cover, that hold the coaster brake bracket and holds the guts of the hub inside ?
(there's on on each side) before then putting on the locking nuts,..?
are these to be just hand tight so it will spin freely,...?
for that matter how tight so you work in the thread end of the sprocket into the hub,,...?

also, I have a small red washer or round gasket I don't know where it goes,...? any idea's,...?
 
small red washer is a fiber washer, probably for the petcock so it doesn't leak, if it's smaller than the petcock, it's for the carb, but there should be one on there already. it's just a sealing washer.

as for the coaster brake "cones" needing to be tightened, the answer is yes, but they need to be done a certain way so it's all adjusted correctly.

for that. lemme refer you to the late, great bicycle guru extraordinaire, Sheldon Brown:

One-Speed Bicycle Coaster Brakes
 
Dsavage21 said:
Hey guys, I'm looking into building a bike and I'm curious how to mount the rear sprocket for AGK. it doesn't say anything on the website, does it just come with the rubber pads and bolts?
This is the sprocket:
http://www.affordablegokarts.com/mm...Product_Code=5321**&Category_Code=MTRBK+PARTS
Click to expand...

Hello DSavage welcome to the forum, glad you joined us.

Here is what I read
designed to fit 6 bolt hubs
Click to expand...

So, I would assume its made to bolt to disc hubs
 
I brought my sprocket to a local machine shop along with my hub and the guy machined out the center of the sprocket and charged me a large Dunkin Donuts coffee for the work! The benefit of this is that the hole is widened but still perfectly centered so I didn't run into problems getting the sprocket to mount in the right place with no wobble.
 
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